sentry sr laser level monitor operation manual - gilson … manuals/optech/sentrysr_operation... ·...

Optech IncorporatedIndustrial Products Division

Sentry SRLaser Level Monitor Operation Manual

Optech IncorporatedIndustrial Products Division

100 Wildcat RoadToronto, Ontario, Canada M3J 2Z9

Tel: 1-416-661-5904 Fax: 1-416-661-4168E-mail: [email protected]: www.optech.on.ca

Document No. 290000611/Rev B March 2004

Shipping DamageThis unit is inspected before shipment. As soon as the unit is received from the carrier, and before operation, inspect the unit for damage that may have occurred during shipment. If any damage is found, file a claim promptly with the carrier and notify Optech immediately.

Return of UnitBefore returning this unit, contact Optech to obtain a Return Authorization (RA) number. Optech will not accept units without an RA number.

Opening the UnitThis unit should not be opened at any time except by qualified personnel. If the unit is opened by unqualified personnel the protection provided by equipment may be impaired.

Copyright© Copyright 2004 by Optech Incorporated. All rights reserved. This item and the information contained herein are the property of Optech Incorporated. No part of this document may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or computer language in any form or by any means otherwise, without the express written permission of Optech Incorporated, 100 Wildcat Road, Toronto, Ontario, Canada M3J 2Z9.

Revision HistoryRevision Date Description

A Feb 04 Optech Release

B Mar 04 Update

Table of Contents

Page

1 ABOUT THIS MANUAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Who Should Read This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Alerts and Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Type Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2 SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Visible Laser Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3 PRODUCT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Principle of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Description and Enclosure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Cooling Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Programming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Eye Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Environmental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Enclosure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11System Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

5 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Installation Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Install . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Cable and Power. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Align and Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Final Steps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Disconnecting the AC Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Cabling and Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Signal and Data Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Serial Data Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Mounting Configurations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Surface Mounting and Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Flange Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Application Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Monitoring Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Monitoring Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

6 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Operating Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Powering ON/OFF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Accuracy and Repeatability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Accuracy Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Low-Temperature Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Thermal Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25High-Temperature Laser Pointer Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Heater Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

7 PROGRAMMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Hand-Held Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Using the Programming Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Programming the Laser Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Main Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Key Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Measurement Units for Range Readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Resolution of Range Readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Laser Trigger Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Analog Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314 mA and 20 mA Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Saturation and No Range Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Modes Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Output Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Mode of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Filter Distance and Time Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Filter Distance: One-Way. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Filter Time Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Examples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Relay Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Alarm Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Range Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Rate Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8 USING THE HART SOFTWARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Connecting the Sentry SR to your PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39The HART Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Using the HART Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Main Menu > Device Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Device Setup > Application Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Device Setup > Update Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Device Setup > PV Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Device Setup > Output Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Device Setup > Line of Sight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Device Setup > Trigger Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Device Setup > Analog Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Device Setup > Relay Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Device Setup > Laser Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Device Setup > HART Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Device Setup > Device Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Main Menu > Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Main Menu > PV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

9 MAINTENANCE AND SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Enclosure Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Service and Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

10 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Diagnostic LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61No Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62Intermittent Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Erratic, Fluctuating or Short Readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Local Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

List of TablesPage

Table 1: J1 DC Power Input for 24 V Rated Models(Standard DC Operation, Field Interface Card) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Table 2: J1 AC Power Input for 120 V and 230 V Rated Models(Optional AC Operation, Field Interface Card) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Table 3: J3: Relay Contact 2 (AC or DC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Table 4: J2: Relay Contact 1 (AC or DC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Table 5: J3 4-20 mA ANALOG(DC and AC Operation, Power Supply Board) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Table 6: J4 EXTERNAL TRIGGER(DC and AC Operation, Power Supply Board) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Table 7: J5 RS-232C(DC and AC Operation, Power Supply Board) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Table 8: Common Programming Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Table 9: Programmable Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Table 10: Replaceable Fuses - DC Operation (Standard) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Table 11: Replaceable Fuses - AC Operation (Option). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Table 12: Troubleshooting Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Table 13: Diagnostic LEDs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Table 14: Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

SentrySR Laser Level Monitor Operation Manual About This Manual

290000611/Rev B/Mar 04 1

1 ABOUT THIS MANUAL

Contents 1.1 Who Should Read This Manual1.2 Alerts and Notices1.3 Type Conventions

1.1 Who Should Read This ManualThis manual is intended for plant personnel and other users of the Sentry SR laser level monitor.

1.2 Alerts and NoticesTo highlight important information, this manual uses the following signal words. Do not proceed until you understand the information and have complied with any instructions:

WARNINGPotential for death or serious injury.

CAUTIONPotential for minor or moderate injury; unsafe practices.

NOTICEDamage to equipment or loss of data; policy on safety of personnel or protection of property.

IMPORTANTOperation or maintenance suggestion; other useful information

About This Manual SentrySR Laser Level Monitor Operation Manual

2 290000611/Rev B/Mar 04

1.3 Type ConventionsThis manual uses the following type conventions:

J2 Sans-serif font for hardware labels.Range Monospace font for screen text displayed on, or entered via, handheld con-

troller or PC.

Sentry SR Laser Level Monitor Operation Manual Safety

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2 SAFETY

Contents 2.1 Visible Laser Pointer2.2 Warning

2.1 Visible Laser Pointer

The Sentry SR has two laser sources contained in the unit. There is an invisible Infrared (IR) beam used for the range measurement and there is a visible beam used for alignment of the unit.

The infrared (IR) laser emits energy that is not visible to the human eye. It is designed as a Class 1M laser source as specified by IEC 60825-1:1993+A1:1997+A2:2001. Under normal operation the IR laser is not considered hazardous. In normal installation and use, a person may view the laser light with the naked eye or with eyeglasses assisting vision.

The visible laser pointer is classified as a Class 2 laser product per IEC 60825-1: 1993+A1:1997+A2:2001. Class 2 denotes low power visible lasers or laser systems that, because of normal human aversion responses, do not usually present a hazard. In normal installation and use, a person may view the laser light with the naked eye or with eyeglasses assisting vision. The laser pointer emits continuous visible laser light at a wavelength of 650 nm.

The laser light has an optical power of less than 1 mW and a laser spot diameter of less than 15 mm at a range of 5 m. The laser pointer is co-aligned with the rangefinder beam, and projects a red spot on any surface. Note that this beam spot may be hard to see in bright light.

CAUTIONIf this equipment is used in a manner not specified in this manual, the protection provided by the equipment may be impaired.

CAUTION Visible Laser Light - Do not Stare into BeamUse of controls or adjustments or performance of procedures other than those specified herein may result in hazardous exposure to laser light.

Use of optical instruments with pointer may increase eye hazard.

Program laser pointer to OFF after installation and alignment.

Safety Sentry SR Laser Level Monitor Operation Manual

4 290000611/Rev B/Mar 04

The Sentry SR is considered a Class 2M product per IEC 60825-1: 1993+A1:1997+A2:2001 when the two laser beams are considered together. The Sentry SR is labeled as a Class 2M product and the two labels on the unit are shown in Figure 1. This labeling and classification system ensure that the Sentry SR complies with all requirements of the European eye safety standard (IEC 60825-1:1993+A1:1997+A2:2001) and with United States eye safety standard (CFR 1040, parts 10 and 11, and Laser Notice 50, dated July 2001).

As with many conventional light sources, there can be some potential for hazard if the laser light is viewed directly for long periods.

Do not use optical instruments such as binoculars or other devices that collect light while the laser pointer is firing. As a standard laser precaution, do not stare directly into the laser, and do not install the Sentry SR at eye level.

Use the laser pointer for alignment only, and not in normal operation. To prevent accidental exposure to the laser beam, Optech strongly recommends that you program the pointer OFF through software as soon as the Sentry SR is installed and aligned. As a precaution, the pointer always defaults to OFF upon power-up.

Figure 1: IEC Eye Safety Labels

2.2 Warning

WARNING Shock HazardDo not open enclosure when unit is powered. Only qualified personnel should open Sentry SR and handle wiring and connectors.

Sentry SR Laser Level Monitor Operation Manual Product Description

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3 PRODUCT DESCRIPTION

Contents 3.1 Principle of Operation3.2 Description and Enclosure3.3 Lasers3.4 Programming3.5 Outputs

3.1 Principle of OperationThe rangefinder uses a pulsed laser to make non-contact range measurements to almost any material, operating in both dark and well-lit environments without using retro-reflectors or mirrors. The narrow laser beam produces no false echoes and resolves small targets at long range. It can be reflected from a diffuse surface at virtually any angle and still return to the unit to produce a range measurement.

To calculate the range, the time of flight of the laser pulse to and from the material is measured by a high-precision counter, and then converted into a range reading by a microprocessor. By firing the laser rapidly and employing averaging to reduce random errors, the rangefinder produces high-resolution readings independent of range.

3.2 Description and EnclosureThe Sentry SR is a laser-based, non-contact measurement system designed for industrial use as a level monitor. The unit is designed for exceptional, heavy-duty or hazardous operation. With a cooling option, the Sentry SR can also operate in extremely hot environments of up to 150°C.

The Sentry SR consists of a rangefinder housed in a sealed, cylindrical enclosure, with the rangefinder firing through a window at one end (the front). All external power and data connec-tions are made to printed circuit boards (field interface card and power supply board) at the rear of the cylinder. The boards contain terminal blocks, a local RS-232C port and fuses. All cables and connections are made through NPT conduits.

Two diagnostic LEDs are located on the power supply board inside the enclosure. These LEDs, POWER ON (green) and DATA OUT (amber) are only visible when the enclosure is open.

Product Description Sentry SR Laser Level Monitor Operation Manual

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The unit’s enclosure is rated for hazardous operation (for full ratings, see "Enclosure"‚ page 10). You are responsible for maintaining the enclosure rating by re-sealing the enclosure and all NPT conduits.

The Sentry SR is configured for easy flange mounting and versatile surface mounting in any orien-tation. Mounting holes are provided for flexible installation with a mounting bracket. Flange mounting is available as an option.

The Sentry SR operates from a nominal input voltage of 24 VDC (120 VAC/220VAC option avail-able). Power input and analog data input/output are isolated up to 1500 VDC. The local RS-232C port is not isolated.

3.2.1 Cooling OptionThe cooling option enables the Sentry SR to operate in ambient temperatures of up to 150°C. To keep the temperature inside the enclosure within its specified operating temperature range even when the outside is much hotter, a separate cooling plate is attached to the enclosure.

The cooling plate is designed to be connected to a plant cooling system using an industrial water supply. It has two NPT cooling ports, one serving as the coolant intake and one as the coolant outlet. Heat is transferred by thermal conduction from the enclosure to the coolant circulating through the plate, and removed with the coolant. Cooling installation details are provided on page 21.

3.3 LasersThe Sentry SR uses two laser sources:

Rangefinder laser: Infrared beam (wavelength 905 nm) used to measure distance.Laser pointer: Visible beam (wavelength 650 nm) aligned with the rangefinder

beam.

The laser pointer produces a red spot that indicates the point to which the distance is being measured. The pointer should be used only during installation, to verify alignment.

Sentry SR Laser Level Monitor Operation Manual Product Description

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3.4 ProgrammingEmbedded software enables you to customize many aspects of operation, with an optional keypad providing a simple and convenient user interface. The unit can also be programmed via PC or a Palm computer.

A local, non-isolated RS-232C port can be used during installation to program and test the unit and to monitor range.

All programming software is built into the Sentry SR; no separate software installation is required for use with the handheld keypad or PC.

3.5 OutputsThe Sentry SR outputs accurate range readings in a 4-20 mA format that is compatible with most industrial control and data logging systems. A bi-directional, non-isolated, RS-232C port is provided for local programming. Digital communication over long range is provided by an optional HART modem using the HART protocol.

The Sentry SR also provides two programmable relay outputs. The relays can be set to activate at a preset range (both set and reset values are programmable) or as an alarm.

Specifications Sentry SR Laser Level Monitor Operation Manual

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4 SPECIFICATIONS

Contents 4.1 Measurement4.2 Outputs4.3 Lasers4.4 Eye Safety4.5 Power4.6 Environmental4.7 Enclosure4.8 Options4.9 System Nomenclature

4.1 Measurement

Range 1 0.4 m to 25 mAbsolute accuracy 2 ±2 cm (CP) ±4 cm (DV) Resolution 1 mmRate Programmable from 1 reading every 60 seconds to 5 readings

per secondUnits of measurement Meters or feet

4.2 Outputs

Analog 3 4-20 mA; max. load 1200 ohm; 1500 VDC isolationSerial RS-232C Bi-directional; for test and setup only; not isolatedRelays Programmable for range (set/reset) or alarms

Maximum allowable relay voltage 140 V

1. Maximum ranges are typical and depend upon target reflectance, vessel conditions (e.g., dust) and background radiation.

2. At a measurement rate of 1 reading per second, the specified accuracy is absolute over the full tempera-ture range, with a variety of materials and at any distance, within 1 standard deviation.

3. Analog accuracy is equal to absolute or operating accuracy 0.1% of range.

Sentry SR Laser Level Monitor Operation Manual Specifications

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4.3 LasersWavelengths 905 nm (infrared rangefinder beam)

650 nm (visible laser pointer beam)Infrared beam divergence 4 mrad approx.Infrared spot size 3 x 1 cm at exit apertureVisible beam divergence <5 mradVisible spot size 3.5 x 5.8 mm @ 7 m

4.4 Eye SafetyVisible laser pointer Class 2 (US FDA 21 CFR 1040)

Class 2 (IEC 60825)IR rangefinder laser Class 1 (US FDA 21 CFR 1040)

Class 1M (IEC 60825)

4.5 PowerInput: 24 VDC model 24 VDC; current 420mA (4.2 A with heater option)Voltage tolerance 11-30 VDC

Input: 120 VAC model 120 V, 50/60 Hz; current 180 mA (625 mA with heater option) Voltage tolerance 108-132V (±10%)

Input: 230 VAC model 230 V, 50/60 Hz; current 100 mA (330 mA with heater option) Voltage tolerance 207-253 V (±10%),

Overvoltage category/installation category Category II

Specifications Sentry SR Laser Level Monitor Operation Manual

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4.6 EnvironmentalOperating temperature 0°C to +50°C With AC or DC heater -40°C to +50°C With cooling option 0°C to +150°CStorage temperature -40° C to +70°CRelative humidity rating 10 to 95% RH, non-condensingMax. altitude 2000 m

Cooling System (Option)Type WaterWater temperature Up to 25°CFlow rate 2.3 litres/minute (0.5 gallons/minute)Pressure Minimum required to maintain flow ratePorts 1/4” NPT

4.7 EnclosureRatings Class I, Div 1, Groups B, C and D

Class I, Div 2, Groups A, B, C and DClass II, Div 1 and 2, Groups E, F and G Class III, Div 1 and 2Zone 1 and 2, Groups IIA, IIB and IICNEMA 4, 4X, IP65EE x d IIB + Hydrogen

Size 127 W x 305 L (mm); 5” W x 12” L)Weight 6.2 kg (13.5 lbs.)Standard mounting Articulating bracketOptional mounting Flange mounting: ANSI 2”, 3”, 4”, 6”, 8”; 150#, 300#, 600#

flanges

Sentry SR Laser Level Monitor Operation Manual Specifications

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4.8 Options

Hand-Held KeypadDisplay 4 lines x 20 characters liquid crystal displayCase Molded, high impact ABSOperating temperature 0°C to +50°CStorage temperature -20°C to +70°C

Note: Models incorporating both a heater option and a cooling option are not available.

All specifications are subject to change without notice.

4.9 System Nomenclature

CODE ENCLOSURE TYPE

SSR-CPSSR-DV

Sentry Clear Path ModelSentry Dust and Vapour Model

CODE INPUT POWER OPTION

DC

DH

ACAH

ECEH

24V DC Input Power (included in base unit), T6, Ta = 50°C24V DC Input Power w/ heater for T6, Ta = -40-50°C

120 VAC Input Power, T6, Ta = 50°C 120 VAC Input Power w/ heater for T6, Ta = -40-50°C

230 VAC Input Power, T6, Ta = 50°C230 VAC Input Power w/ heater for T6, Ta = -40-50°C

CODE COOLING OPTION

C

N

Cooling Plate (units containing a cooling plate are T6, Ta = 150°CNo Cooling Plate

CODE COMMUNICATION

DH

RS-232CHART Protocol

SSR-CP AH C D TYPICAL NOMENCLATURE

Installation Sentry SR Laser Level Monitor Operation Manual

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5 INSTALLATION

Contents 5.1 Installation Procedure5.2 Disconnecting the AC Power Supply5.3 Cabling and Electrical Connections5.4 Mounting5.5 Cooling System5.6 Application Information

5.1 Installation Procedure

Before installing the Sentry SR, ensure that you are familiar with the cabling, mounting and other information presented in this chapter.

5.1.1 Install1. Locate a suitable installation site ("Application Information"‚ page 21).

2. Install the mounting bracket on the enclosure, using 5/16 x 24 UNF bolts. Use two bolts on each side of the enclosure to position and align the unit properly.

3. Install the unit and bracket on location, using a 3/4 x 10 UNC bolt. Do not secure the unit in place until final alignment is complete. Note that the unit’s position must be measured after it is aligned.

CAUTION Visible and Invisible Laser Light - Do not Stare into BeamProgram laser pointer to OFF before closing enclosure.Sentry SR may fire as soon as power is supplied.

NOTICEDo not point Sentry SR directly at sun. Strong sunlight reflections can cause erratic range readings.

NOTICEPlease ensure that the protective earthing terminal on the outside of the enclosure is connected to a proper ground.

Sentry SR Laser Level Monitor Operation Manual Installation

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5.1.2 Cable and Power1. Loosen and remove the set screws from the rear cap of the enclosure, and then remove the

rear cap. Do not remove the cap with the window.

2. Remove the coloured plugs on the cable conduits to begin cabling. There are two NPT threaded conduits, with diameters of 1/2” and 3/4”.

3. Run your power and data cables through the cable conduits.

4. Make all connections to the field interface card and power supply board, using the terminal information on page 15 and after. The unit is powered from either 24 VDC, 120 VAC, or 230 VAC.

5. Attach the ferrite core to the cable. The ferrite core must be installed on all unshielded cable connections (both power and analog).

6. For local RS-232C test and programming, plug in the optional keypad or remote device to J5 on the power supply board. To use a remote device other than a keypad or a laptop computer, see "Serial Data Protocol"‚ page 18.

7. Power ON. Check that the green POWER ON LED inside the enclosure is lit.

5.1.3 Align and Program1. Program the laser pointer ON (page 29).

2. As the unit begins to fire, locate the red pointer beam spot. The pointer beam spot is co-aligned with the rangefinder beam.

3. Align the unit.

Use shims or washers to adjust the position of the unit until it is properly aligned. If the instal-lation includes a sightglass, use a gasket to mount the unit tightly to the sightglass.

4. When the unit is aligned, program the laser pointer OFF.

5. Program the unit for plant operation (page 12).

CAUTION To maintain CE approvals, a ferrite core must be installed on all unshielded cable con-nections (power and analog). Steward part number 28A0640-0A* is specified and can be supplied with the unit.

CAUTION Visible and Invisible Laser Light - Do not Stare into BeamDo not use binoculars or devices that collect light to locate the pointer beam.


14 290000611/Rev B/Mar 04

5.1.4 Final Steps1. Power OFF, and unplug the RS-232C data cable.

2. Replace the rear cap of the enclosure, and tighten the cap and the set screws.

3. Seal the conduit entry holes.

4. Measure the position of the unit.

5. Begin operation (page 23).

5.2 Disconnecting the AC Power SupplySince the Sentry SR does not have a switch or circuit breaker, a switch or circuit breaker for the AC power must be located within easy reach (maximum 3 metres) of the operator. This switch must be labelled as the disconnect device for the Sentry SR and it must meet the requirements of IEC 60947-1 and IEC 60947-3. These standards ensure that the switch has a minimum air gap of 3 mm.

5.3 Cabling and Electrical Connections

To simplify cabling and servicing, all external data and power connections are made to the rear of the enclosure. Two NPT conduit entry holes (1/2” and 3/4”) are provided at the rear.

Connections are made either to the field interface card, which contains fuses and terminal con-nectors, or to the power supply board, which holds the two diagnostic LEDs as well as several connectors. While the surface of the field interface card is visible, only one edge of the power supply board is accessible. Connectors and LEDs are located on this edge.

NOTICEFailure to maintain sealed conduit entry holes will void warranty.

IMPORTANTPower and data cables supplied by customer are required for operation.Sentry SR may fire as soon as power is supplied.


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Table 1: J1 DC Power Input for 24 V Rated Models(Standard DC Operation, Field Interface Card)

Terminal Connection

1 +24 VDC

2 24 VDC Return

Block Part # LMI components 102302-01.000

Wire Specifications

≤ 2.5 mm2, 22-14 AWG, 15, 300 V

Temp 80°Cif used in environment where temper-ature exceeds this rating (i.e., 150°C) suitable wire must be used

Insulation ≤ 0.4 mm

Table 2: J1 AC Power Input for 120 V and 230 V Rated Models(Optional AC Operation, Field Interface Card)

Terminal Connection

1 Line

2 Neutral

3 Ground


Wire Specifications

≥ 2.5 mm2, 22-14 AWG, 15, 300 V




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Table 3: J3: Relay Contact 2 (AC or DC)

Terminal Connection

1 Normally Closed Relay 2

2 Normally Open Relay 2

3 Common Relay 2


Wire Specifications

≥ 2.5 mm2, 22-14 AWG, 15, 300 V

Temp 80°Cif used in environment where temper-ature exceeds this rating (i.e., 150ºC) suitable wire must be used


Table 4: J2: Relay Contact 1 (AC or DC)

Terminal Connection

1 Normally Closed Relay 1

2 Normally Open Relay 1

3 Common Relay 1


Wire Specifications

≥ 2.5 mm2, 22-14 AWG, 15, 300 V




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The external trigger input is a TTL, active high, input: the unit fires at the programmed repetition rate as long as the input is held high.

Table 5: J3 4-20 mA ANALOG(DC and AC Operation, Power Supply Board)

Terminal Connection

+ Analog Current Loop 4-20 mA +

- Analog Current Loop 4-20 mA -

Block Part # Phoenix MKDSFW 1, 5/2

Wire Specifications

0.14 - 2.5 mm2, 26-14 AWG, 17.5 A, 320 V

Temp 80ºCif used in environment where temper-ature exceeds this rating (i.e., 150ºC) suitable wire must be used


Table 6: J4 EXTERNAL TRIGGER(DC and AC Operation, Power Supply Board)

Terminal Connection

+ LASER ENABLE

- LASER ENABLE

Block Part # Phoenix MKDSFW 1, 5/2

Wire Specifications

0.14 - 2.5 mm2, 26-14 AWG, 17.5 A, 320 V




18 290000611/Rev B/Mar 04

This non-isolated connector is intended for local test, installation and alignment with a keypad or other serial communication device. It is not intended to be permanently connected to a control system.

5.3.1 Signal and Data IsolationThe power and analog current loop lines are isolated to 1500 VDC. The RS-232C port is not isolated. Before making connections to this port, determine whether a ground fault exists.

5.3.2 Serial Data Protocol

Serial RS-232C communication is established via the optional keypad.

All programming software is embedded and available as soon as serial communication is estab-lished. Programming screens are shown on the range display.

Table 7: J5 RS-232C(DC and AC Operation, Power Supply Board)

Pin Connection

1 Remote +10 V

2 N/C

3 N/C

4 RS-232C Tx

5 RS-232C Rx

6 Data Ground

Part # Kycon GM-N-66

Wire Specifications

6 pos. modular jackCurrent rating 1.5 A

NOTICEBefore starting PC programming, press CAPS LOCK.


290000611/Rev B/Mar 04 19

If you want to store readings or do not have a keypad, you can use a PC instead. The Sentry SR interfaces easily with any PC terminal communications program. To establish a serial data con-nection, your computer must be equipped with an RS-232C port.

Use the following settings:RS-232C Tx RxASCII charactersBaud rate 19,200Data bits 8Stop bits 1Parity NoneFlow control None (Xon/Xoff)Serial port According to your computer configuration.

If your PC is equipped with Windows 3.1™ software, follow these steps:

1. Select the ACCESSORIES icon.

2. Select TERMINAL, and then SETTINGS and COMMUNICATIONS.

3. Set communications parameters as listed above.

4. Save the correct settings to a file for quick recall.

For Windows 98™ or Windows NT™, use the HyperTerminal program with the above steps.

5.4 MountingThe Sentry SR enclosure provides a variety of mounting options to suit specific applications and installations. By using the standard U-shaped mounting bracket, the enclosure can be positioned in any orientation or at any angle.

The mounting bracket has the following mounting points:

Sentry SR to bracket: Two holes for 5/16 x 24 UNF bolts, on each side of the Sentry SR enclosure.

Bracket to plant installation site: One hole for 3/4 x 10 UNC bolt, on the base of the bracket.


20 290000611/Rev B/Mar 04

5.4.1 Mounting Configurations

5.4.1.1 Surface Mounting and Alignment

• Ensure that the support is sufficiently rigid to prevent misalignment.

• Before drilling through holes into the support, consider any future alignment problems or equipment that may obstruct the rangefinder beam.

• The degree of alignment depends upon the size of the mounting hole. To facilitate alignment, use an oversized hole with suitable clearance.

• To ensure the correct vertical alignment, use shims or washers.

5.4.1.2 Flange Mounting

• When installing the Sentry SR in its flange-mount bracket, consider the location of the mounting brackets in relation to the stud pattern on the mounting base, to take advantage of any inclination angle.

• When using a sightglass, cross-tighten the flange nuts to avoid putting a bending moment on the sightglass.

• Obey the bolting torque limits specified by the manufacturer for the size and material of the flange stud being used.

• Before final installation, clean all surfaces and seal them with suitable gaskets. Avoid invasive dust or moisture.

• Do not complete the final seal of the window assembly to the sightglass cover until the unit has been fully aligned and commissioned.


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5.5 Cooling SystemA cooling option is available for operation in hot environments up to 150°C. With this option, the Sentry SR is cooled by thermal conduction from the enclosure to the liquid coolant circulating through a cooling plate attached to the enclosure.

Use a flow rate of at least 2.3 litre/minute (0.5 gallon/minute), with a water temperature of up to 25°C. Use the minimum pressure required to maintain an acceptable flow rate. Industrial water is sufficient as a coolant.

To connect the Sentry SR to your cooling system:

1. Attach the cooling plate to the enclosure, using four #10 mounting screws.

2. Install the coolant intake to one of the 1/4” NPT fittings on the cooling plate (either fitting can be used).

3. Install the coolant outlet to the other fitting. Do not restrict the outlet coolant flow in any way.

5.6 Application Information

5.6.1 Monitoring Liquids• Install the Sentry SR to range towards the liquid at an angle of 90°.

• For outside installation, consider the angle at which the sun strikes the liquid. A strong sunlight reflection can cause out-of-range measurements.

• Ensure that the unit will not be ranging to obstacles that may be hidden at the time of installa-tion.

• The Sentry SR works best when monitoring turbulent or agitated liquids. Still, motionless liquid with no waves or ripples can cause saturation problems and less accurate range readings. Specular reflections from the surface of the liquid may produce NO RANGE errors (Table 14, page 61).

• In environments with dust, airborne particles, steam or fog, use last-pulse measurement mode (page 33). If problems persist, contact Optech.

• To ignore range readings from tank agitation and obstacles such as mixer blades, use filter option programming (page 34).

• If measurements are intermittent, use filter option programming to compensate.


22 290000611/Rev B/Mar 04

5.6.2 Monitoring Solids• Incorrect readings may be reported during filling. Depending upon the size of the falling par-

ticles, the range to the unit, and the extent of the drop, the Sentry SR may be able to range through the particles during a fill cycle.

• The alignment of the unit can be adjusted to range to the top of a cone on filling, and to the bottom of a cone on emptying.

• Ensure that the unit will not be ranging to obstacles that may be hidden at the time of installa-tion.

• In environments with dust, airborne particles, steam or fog, use last-pulse measurement mode (page 33). If problems persist, contact Optech.

• If measurements are intermittent, use filter option programming to compensate (page 34).

Sentry SR Laser Level Monitor Operation Manual Operation

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6 OPERATION

Contents 6.1 Operating Steps6.2 Powering ON/OFF6.3 Accuracy6.4 Thermal Protection

The Sentry SR can be programmed and controlled remotely from the hand-held keypad or any device communicating via RS-232C and using ASCII characters. Programming is discussed in Chapter 7, Programming, on page 26, and Chapter 8, Using the HART Software, on page 39.

Factory settings or the most recent programmed settings are saved and restored when the unit is powered ON again.

6.1 Operating Steps1. (Cooling option) Check that coolant is circulating through the cooling plate ("Cooling

System"‚ page 21).

2. Before powering the unit, check that:• Interface cables are firmly attached at both ends and will not come loose.• If using a PC, it is properly configured for remote programming, and CAPS LOCK is on

("Serial Data Protocol"‚ page 18).

3. Power ON.The software version is briefly displayed on your keypad or PC. In continuous mode, the Sentry SR begins to report range readings within seconds. In external trigger mode, the unit reports readings only when triggered.

Review and follow the laser safety precautions ("Visible Laser Pointer"‚ page 3).

4. Program the unit (page 26). Review also the operating notes in this chapter and the suggestions in "Application Informa-tion"‚ page 21. Programming software is embedded; no separate software installation is nec-essary.

5. In external trigger mode, trigger range readings (Table 6, page 17).

6. Monitor range readings, and change programmable settings as desired.

Operation Sentry SR Laser Level Monitor Operation Manual

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6.2 Powering ON/OFFThe Sentry SR has no power ON/OFF switch. It is turned ON/OFF by the external power source.

Note that the laser pointer fires continuously if it is programmed ON.

6.3 Accuracy

6.3.1 Accuracy and RepeatabilityThe Sentry SR averages a number of laser shots to produce each range reading. The number of shots averaged affects the level of accuracy of a reading: the higher the number of shots, the higher the accuracy of the resulting reading. Since the Sentry SR fires a fixed number of shots per second, the measurement update rate (rate of readings) determines the number of shots that can be averaged, and thus the accuracy of the range reading:

Level of Accuracy decreases as the Measurement Update Rate increases.

6.3.2 Accuracy RestrictionsAt short range, a very strong return from a highly reflective target such as reflective tape will saturate the Sentry SR’s range detector, and may produce a range reading with a degraded accuracy. In this case a SATURATION error code will be output with the range (Table 14, page 61).

A highly reflective target may produce an inaccurate range reading owing to saturation. Blocking part of the exit aperture will correct this effect.

6.3.3 Low-Temperature StartIf the Sentry SR is powered on when it is below its operating temperature, initial range readings may fluctuate. Range accuracy will gradually improve as the unit’s internal temperature stabi-lizes.

Sentry SR Laser Level Monitor Operation Manual Operation

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6.4 Thermal Protection

6.4.1 High-Temperature Laser Pointer ProtectionTo protect the laser pointer from temperature extremes above its specified operating range, the laser pointer is shut down automatically when the ambient temperature exceeds about 40°C. The pointer is automatically re-enabled when the temperature drops.

6.4.2 Heater OptionsFor operation in cold environments, an AC or DC heater option is recommended. The heater will ensure the unit is at an acceptable operating temperature before operation and output begin.

Programming Sentry SR Laser Level Monitor Operation Manual

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7 PROGRAMMING

Contents 7.1 Overview7.2 Programming the Laser Pointer7.3 Main Screen7.4 Key Screens7.5 Analog Screens7.6 Modes Screens7.7 Rate Screens

7.1 Overview

7.1.1 Hand-Held KeypadTo facilitate test and setup in an operational environment, an optional hand-held keypad is used. The keypad uses RS-232C communication and plugs into J5 on the power supply board. It can be connected or disconnected at any time while the unit is powered ON.

IMPORTANTTo begin programming, press M.

Current setting is highlighted on-screen.

Most recent programmed settings are restored when unit powered ON (laser pointer defaults to OFF).

Rangefinder laser does not fire during programming. Laser pointer continues to fire if programmed ON.

Programming software is embedded; no separate software installation is necessary.

Sentry SR Laser Level Monitor Operation Manual Programming

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7.1.2 Using the Programming ScreensWhen programming on PC, first ensure that CAPS LOCK is on. The programming screens are formatted for the keypad, and do not look the same when displayed on a PC. The table below describes some of the most common screen operations.

Table 8: Common Programming Operations

Operation Step

Begin programming. Press M.

Previous screen Press P.

Next screen Press N.

Backspace over an entry (keypad)

Hold down SHIFT and press BACKSP.


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Table 9: Programmable Settings

Setting Options

Measurement Units Meters, feet

Resolution Low: 0.00 m (1 cm) or 0.1 ftHigh: 0.000 m (1 mm) or 0.01 ft

Trigger Mode Continuous: Unit internally triggered to output range readings at selected update rate.External Trigger: Unit outputs a range reading when externally triggered.

Analog Settings(zero, span, inverse span)

20 mA: 0 to 50,000 cm 4 mA: 0 to 50,000 cm

Analog Settings(saturation, no range)

High: If saturated or no range, send 20 mA.Low: If saturated or no range, Send 4 mA.Hold Last Valid: Send last valid range.

Output Mode Direct: Material moving at >30 cm (1 ft.) per minute.Extra Averaging: Material moving at <30 cm (1 ft.) per minute.

First/Last Pulse Mode First Pulse: Use with a clear and unobstructed view of the material.Last Pulse: Use with interference such as fog, rain, dust, snow or objects between the unit and the material.Filtered Last: Use with heavy interference when lower accuracy is acceptable.

Filter Filter Distance: Range window for valid readings (0-20 m).Filter Time Out: Number of readings for which window distance is valid.

Relays Set for Alarm: Relay is activated by alarm.Set for Range: Relay is activated by range.

Update Rate From 5 readings per second to one reading every 60 seconds.


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7.2 Programming the Laser Pointer

To program the laser pointer ON/OFF, press P at any time outside the programming screens.

The laser pointer is intended to help align the unit during installation and test only. The pointer defaults to OFF upon power-up:

ON For alignmentOFF At all other times.

For more information, see "Visible Laser Pointer"‚ page 3.

7.3 Main ScreenWhen you press M to begin programming, the following screen appears.

SETTINGS Allows you to change the programmed settings.SETTING REVIEW Allows you to review the programmed settings.PROC. VARIABLE The unit begins operation and outputs the process;

variable based on programmed settings.

The rangefinder laser does not fire during programming, but the laser pointer continues to fire if it is programmed ON.

CAUTION Visible Laser Light - Do not Stare into BeamDo not use binoculars or devices that collect light.

SENTRY SRA SETTINGSB SETTING REVIEWC PROC. VARIABLE


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7.4 Key Screens

7.4.1 Measurement Units for Range Readings

7.4.2 Resolution of Range Readings

Resolution: Example:A LOW 0.00 m (1 cm) or 0.1 ft. 7.54 m, 24.1 ft.B HIGH 0.000 m (1 mm) or 0.01 ft. 7.545 m, 24.17 ft.

7.4.3 Laser Trigger Mode

A CONTINUOUS Internally triggered to output range readings at selected update rate.B EXT. TRIGGER Outputs a range reading when externally triggered (Table 6, page 17).

To switch between trigger modes outside the menus, press the following keys:

Continuous mode Press C.

External trigger mode Press S.

MEASUREMENT UNITSA METERSB FEET

RESOLUTIONA LOWB HIGH

TRIGGER MODEA CONTINUOUSB EXTERNAL TRIGGER


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7.5 Analog Screens

7.5.1 4 mA and 20 mA Limits

These screens set the ranges corresponding to the 4 mA and 20 mA analog limits. Ranges can be set for zero, span, and inverse span, and are displayed in the current units of measurement (centi-meters or inches). The maximum range is 2000 cm (20 m).

Note that the value of the analog limit is exact if centimeters are used, but round-off errors reduce the accuracy using feet to under one inch.

When you press A to change the limit, the following prompt appears:

INPUT A NEW NUMBER FOR THE SETTING AND PRESS <ENTER>

Type a value and press ENTER.

ANALOG SETTINGSA 20 mA LIMIT C SATURAT.B 4 mA LIMIT D NO RANGE

20 mA LIMIT IS 3000 cm Press A to change

4 mA LIMIT IS 0 cm Press A to change


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7.5.2 Saturation and No Range Settings

A 4 mA Sends analog high if the signal is saturated or missing.B 20 mA Sends analog low under the above conditions.C HOLD LAST VALID Sends the last valid signal under the above conditions.

SET ANALOG ALARM OUTPUT FOR NO RANGEA 4 mAB 20 mAC HOLD LAST VALID


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7.6 Modes Screens

7.6.1 Output Mode

A DIRECTSuitable where the level of material changes at more than 30 cm (1 foot) per minute. This mode is best for fast-moving material or quickly changing situa-tions. It sets the unit to calculate the average range from the latest burst of laser shots.

B EXTRA AVERAGINGSuitable where the level of material changes at less than 30 cm (1 foot) per minute. This mode is best for slow-moving material. It sets the unit to calculate the average range from the latest as well as the previous burst of laser shots.

7.6.2 Mode of Operation

A FIRST PULSE This mode is best if there is a clear and unobstructed view of the material, with no fog, steam, rain, snow, dust or other possible targets in the way. Range read-ings are made to the first object encountered.

B LAST PULSEThis mode improves ranging through fog, steam, rain, snow or certain quantities of dust. It can provide the correct range even if stationary objects partly block the unit’s line of sight, as long as the objects are separated by more than 3 m (10 feet) and part of the laser beam travels beyond them. Range readings are made to the last object encountered, filtering out earlier returns.

C FILTERED LASTThe rangefinder is now optimized to range through very thick fog, steam, rain, snow or dust. This mode provides usable and stable ranges at the cost of possible lower accuracy (±0.5 to 8 cm). Note that the unit relies on line of sight; laser light must be able to reach the material and return to the unit for a measurement to be made.

OUTPUT MODEA DIRECTB EXTRA AVERAGING

A FIRST PULSE B LAST PULSEC FILTERED LAST


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7.6.3 Filter Distance and Time Out

These screens provide a sliding filter for both the analog and serial output. The Sentry SR assumes that the longest readings are valid, and therefore uses a one-way filter to ignore short readings outside the window. This screens out interference and obstacles passing between the unit and the material it is monitoring.

A valid reading within the filter distance resets the reference for the next measurement.

7.6.4 Filter Distance: One-WayThe filter distance determines how much shorter a valid reading can be from the previous reading. Any shorter reading outside the window is ignored, while all readings longer than the previous one are considered valid. The maximum window distance is 2000 cm (20 m).

The unit re-transmits the last valid measurement until another valid measurement occurs or the programmable filter time out expires.

FILTER VALUESA FILTER DISTANCEB FILTER TIME OUT

FILTER DISTANCE IS 0 cm Press A to change

FILTER TIME OUT IS 0 Press A to change


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7.6.5 Filter Time OutThe filter time out, measured in number of readings, determines the number of readings for which the filter distance applies. After the time out expires, the next measurement is valid whether it is within this distance or not. The maximum time out value is 255.

The FILTER DISTANCE screen displays the current value in the current units of measurement (centimeters or inches); the FILTER TIME OUT screen displays the current number of range readings selected for the window. When you press A in either screen, the following prompt appears:

INPUT A NUMBER FOR THE SETTING

Enter the new value, which will be shown at bottom left of the display. Press ENTER to save it, and then E to return to the screen. Check that the correct value is now displayed.

7.6.6 ExamplesFirst range reading 1500 cmFilter distance 200 cmFilter time out 5 range readingsValid reading must be 1300 or greater

If there are no valid measurements, the signal remains at 1500 cm. After five readings, the next range reading is valid whatever it is.

The Sentry SR provides a sliding filter: that is, a valid reading resets the filter for the following readings:

First range reading 1500 cmFilter distance 200 cmFilter time out 5 range readingsValid reading must be 1300 or greater

Second range reading 1400 cmValid reading must be 1200 or greater.


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7.6.7 Relay Screens

The Sentry SR has two relays, each of which can be independently set to be activated by alarms or by ranges:

A SET FOR ALARM Sets the relay to be activated by an alarm (page 36).B SET FOR RANGE Sets the relay to be activated by a range reading (page 37).

By selecting either option in the screen above, you de-activate any settings for the other option.

7.6.7.1 Alarm Settings

When either relay is set to be triggered by an alarm, this screen enables you to set the type of alarm.

A NO SIG. Alarm is triggered if no signal is received from the unit.B SATURATION Alarm is triggered if a saturated signal is received from the unit.C NO SIG. OR SAT. Alarm is triggered both by the absence of a signal and by a satu-

rated signal.

RELAY SETTINGSA RELAY 1B RELAY 2

RELAY 1A SET FOR ALARMB SET FOR RANGE

SET FOR ALARMA NO SIG.B SATURATIONC NO SIG. OR SAT.


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7.6.7.2 Range Settings

When either relay is set to be triggered by a range reading (page 36), this screen enables you to set the ranges.

The RELAY SET POINT or RELAY RESET POINT screen displays the current relay setting in the current units of measurement (centimeters or inches):

SET POINT Sets the range at which the relay is activated.RESET POINT Sets the cross-over point at which the relay is de-activated after it has been

activated.

For example, if the set point is 700 cm and the reset point is 800 cm, all ranges above 700 cm are transmitted. If the ranges exceed 800 cm and then fall back below 800 cm, the reset is activated and no more ranges are transmitted. If the ranges fall below 700 cm and then rise above it, this process begins again.

When you press A in either screen, the following prompt appears:

INPUT A NUMBER FOR THE SETTING


RELAY 1 SET POINT 100 cm Press N for Next Press A to Change

RELAY 1 RESET POINT 100 cm Press N for Next Press A to change


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7.7 Rate Screens

The measurement update rate is a function of the number of shots that are averaged, and is therefore related to the unit’s accuracy and repeatability:

Fastest, least accurate, rate 5 readings per secondSlowest, most accurate, rate 60 seconds per reading.

When you press A in the top screen, the bottom screen appears. If you select A or B in the bottom screen, the following prompt appears:

INPUT A NUMBER FOR THE NEW SETTING


UPDATE RATE IS 1 R/S Press N for NEXT Press A to change

UPDATE RATE ISA 1-5 Readings/SecB 1-5,10,30,60 S/R

Sentry SR Laser Level Monitor Operation Manual Using the HART Software

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8 USING THE HART SOFTWARE

Contents 8.1 Installation8.2 Connecting the Sentry SR to your PC8.3 The HART InterfaceUsing the HART Software8.4 Using the HART Software8.5 Main Menu8.6 Main Menu > Device Setup8.7 Main Menu > Review8.8 Main Menu > PV

8.1 InstallationThe HART Communicator software will be installed by the technician.

8.2 Connecting the Sentry SR to your PCThe Sentry SR is connected by the supplied RS-232C, or serial, connector. The RS-232C connec-tion must be connected to the computer’s COM1 port.

Using the HART Software Sentry SR Laser Level Monitor Operation Manual

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8.3 The HART InterfaceTo launch the HART Communicator interface, double-click on the HART icon on your desktop. The HART interface main menu appears.

8.4 Using the HART SoftwareTo navigate the HART software, use the arrow keys and the function keys (F1, F2, etc.) on the keyboard:

UP and DOWN arrow keys: Highlight menu optionsRIGHT arrow key: Select optionsLEFT arrow key: Return to the previous screen.

Functions are given at the bottom of the menu. The command corresponds to the function key directly below it; for example, in the image above, press F2 to SAVE.

What follows is a brief description of the main functions of the HART Communicator software. For more information, use the Help function within the HART software.


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8.5 Main MenuFrom the HART Communicator main menu screen you are given three options.

Main Menu

1. Device setup (page 42)2. Review (page 55)3. PV (Process Variables) (page 56)


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8.6 Main Menu > Device SetupUse Device setup to set up the operational parameters for the Sentry SR. You are given 11 choices:

Main Menu

1. Device setup

1.Application Conditions (page 43)

2.Update Rate (page 46)

3.PV Unit (page 47)

4.Output Response (page 48)

5.Line of Sight (page 49)

6.Trigger Mode (page 50)

7.Analog Output (page 51)

8.Relay Settings (page 52)

9.Laser Pointer (page 53)

10.HART Output (page 53)

11.Device Information (page 54)


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8.6.1 Device Setup > Application ConditionsSetup can be determined by Application Conditions or by Pulse, as seen below.


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Setup by Application Conditions refers to the type of field conditions and the target.

Turbulent: In heavy atmospheric conditions such as dense fog or dust.

Opaque Vapor: More suited to light fog or dust.

Clear & Still: Ideal for no wind and interference.


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Setup by Pulse sets the return signal processing method by First or Last pulse.

First Pulse: Processes the first return signal; usually used for clean applica-tions. Similar to Clear & Still.

Unfiltered Last Pulse: Processes the last signal; generally used in dust and vapor. Similar to Opaque Vapor.

Filtered Last Pulse: Used in extremely high vapor and dust. Similar to Turbulent.


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8.6.2 Device Setup > Update RateUpdate Rate offers two options: Fast Update and Slow Update.

Fast Update Rate: Select a data update rate of 1, 2, 3, 4 or 5 readings per second.

Slow Update Rate: Set the Sentry SR for one reading every 1, 5, 10, 30, or 60 seconds.


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8.6.3 Device Setup > PV UnitSelect this option to configure Process Variable engineering units, which are measured in feet or metres.


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8.6.4 Device Setup > Output ResponseThere are two options under Output Response: Direct and Extra Averaging.

Direct: See every reading at the selected update rate.

Extra Averaging: While the system updates at the selected update rate, the reading is a rolling average of the current reading plus the previous four readings.


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8.6.5 Device Setup > Line of SightLine of sight describes the laser path from the device to the target, either clear or with objects.

Always Clear: Clear, unobstructed path to the target.

Agitators/Objects: Clear out erroneous readings caused by objects in the path.

Selecting Agitators/Objects allows you to set a window threshold, below which all return signals are ignored. For example, if the window threshold is 5 m, no return readings from objects less than 5 m away from the Sentry SR will be recorded.


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8.6.6 Device Setup > Trigger ModeThere are two options for the Trigger Mode: External and Continuous.

External: Manually trigger the device to obtain a reading.

Continuous: Continuously outputs the readings at the selected update rate.


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8.6.7 Device Setup > Analog OutputThere are four options for the Analog Output: URV (Upper Range Value), LRV (Lower Range Value), AO (Analog Output) Saturated and AO-No Range.

URV: Defines the operational endpoint from which the analog value, or 100%, is derived.

LRV: Defines the operational endpoint from which the analog value, or 0%, is derived.

AO-Saturated: Select an analog output to correspond with a saturated return signal.

AO-No Range: Select an analog output to correspond with no return signal.


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8.6.8 Device Setup > Relay SettingsRelay Settings allows you to set conditions to trigger discrete relays. There are two options: Relay 1 and Relay 2. Both offer the option of setting a relay for alarm or range.

Set for Alarm: Set a relay when a specific event occurs, such as loss of signal.

Set for Range: Set a relay when a specific point is reached.


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8.6.9 Device Setup > Laser PointerThis setting allows you to turn the laser pointer on or off.

8.6.10 Device Setup > HART OutputThis allows you to set the polling address and the number of requisite preambles.


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8.6.11 Device Setup > Device InformationThis allows you to set up such information as a text tag, descriptor and date.


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8.7 Main Menu > Review Select Review from the Main Menu to scroll through all the current settings as set up in Main Menu > Device Setup.

Main Menu

1. Device Setup2. Review

1. Model2. PV Units 3. Setup by Appl.4. Setup by Pulse5. USL6. LSL7. URV8. LRV9. Saturated Alarm10. No Range Alarm11. Slow Update Rate12. Fast Update Rate13. Manufacturer14. Relay 1 Alarm15. Relay 1 Set Point16. Relay 1 Reset Point17. Relay 2 Alarm18. Relay 2 Set Point19. Relay 2 Reset Point20. Dev Id21. Tag22. Descriptor23. Message24. Date25. Universal Rev26. Fld dev rev27. Software rev28. Poll Addr29. Num req preambs


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8.8 Main Menu > PVPV ( Process Variables) represents the range from the front of the unit to the target. There are five options in the PV menu. Scroll through the options as set up in Main Menu > PV to review the current settings.

Main Menu

1. Device Setup2. Review3. PV

1. PV2. PV AO3. AO % range4. Intensity5. Dropout

Sentry SR Laser Level Monitor Operation Manual Maintenance and Service

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9 MAINTENANCE AND SERVICE

Contents 9.1 Enclosure Window9.2 Fuses9.3 Storage9.4 Service and Support

9.1 Enclosure WindowClean the window as needed, using a soft lens tissue and a mild, non-abrasive cleanser or soap and water.

Do not use solvents.

9.2 FusesUnit fuses are installed on the field interface card as listed in the tables below. Fuses are installed at the factory for the options ordered. All fuses are slow-blow.

Table 10: Replaceable Fuses - DC Operation (Standard)

Fuse Rating Voltage Rating

Size Function

F1 1 A 250 V 5 x 20 mm Rangefinder

F2 5 A 250 V 5 x 20 mm DC heater

Maintenance and Service Sentry SR Laser Level Monitor Operation Manual

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9.3 StorageStore the Sentry SR in a clean, dry environment between -40°C and +70°C. Note the keypad cannot be stored at temperatures below -20°C.

Cooling option:• Drain all coolant from the cooling plate.• Check that the plate’s internal coolant channels are clean and dry.

Table 11: Replaceable Fuses - AC Operation (Option)

Fuse Rating Voltage Rating

Size Function

F1 1 A 250 V 5 x 20 mm AC heater

F2 0.3 A 250 V 5 x 20 mm Rangefinder

Sentry SR Laser Level Monitor Operation Manual Maintenance and Service

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9.4 Service and SupportOptech is committed to customer satisfaction. Please direct all Sentry SR questions and comments to:

Sentry SR Technical SupportOptech IncorporatedIndustrial Products Division100 Wildcat RoadToronto, Ontario, Canada M3J 2Z9

Telephone: 1-416-661-5904 (8 a.m. - 5 p.m. local time)Facsimile: 1-416-661-4168E-mail: [email protected]: www.optech.on.ca

Before returning a unit, contact Optech to obtain a Return Authorization (RA) number. Optech will not accept units without this number.

Troubleshooting Sentry SR Laser Level Monitor Operation Manual

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10 TROUBLESHOOTING

Contents 10.1 Diagnostic LEDs10.2 Error Codes10.3 No Operation10.4 Intermittent Operation10.5 Erratic, Fluctuating or Short Readings10.6 Local Test

The following table outlines the troubleshooting information in this chapter.

Before contacting Optech, follow the troubleshooting procedures in the table above and then conduct a local test.

Table 12: Troubleshooting Summary

Problem Action

No operation (page 62)

1. Check unit temperature.2. Wait for unit to warm up or cool down.

Intermittent operation (page 63)

1. Check error codes.2. Check unit temperature.3. Check operating environment.4. Check programming values.

Erratic/fluctuating/short readings (page 64)

1. Try filtered last-pulse mode.2. Wait for unit to warm up.

Local test (page 65)

1. Range to a target at a known distance.

Sentry SR Laser Level Monitor Operation Manual Troubleshooting

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10.1 Diagnostic LEDsTwo diagnostic LEDs are installed on the power supply board inside the enclosure. These LEDs are visible only when the enclosure is open.

10.2 Error CodesTable 14 below lists the error codes that can be output. Note that, on the analog output, OUT OF RANGE always appears as the current corresponding to the highest possible range output.

Table 13: Diagnostic LEDs

Label Colour Function

POWER ON Green Power is supplied to the Sentry SR.

DATA OUT Amber Sentry SR is transmitting data.

Table 14: Error Codes

Code Description Serial Output Analog Output

SATURATION Return signal too strong (material highly reflective). Mea-surement valid but may not meet typical accuracy speci-fications.

^ N/A

OUT OF RANGE No laser shots returned to unit. No range provided. NO RANGE 20 mA or 4 mA


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10.3 No Operation1. Check all external cabling, connections and associated equipment.

2. Check that:• All heating and cooling equipment is functioning correctly.• The correct voltage is present at the correct terminals.• The fuses on the interface card are installed and functional.

3. (Cooling option) Check that coolant is circulating through the cooling plate at the correct temperature, pressure and flow rate ("Cooling System"‚ page 21).

4. If the unit is not communicating:• Program the unit for continuous mode ("Laser Trigger Mode"‚ page 30) or send an ASCII

C.• Check that the polarity of the field wiring is correct.

5. For 4-20 mA analog data, check that the analog current at J3 on the power supply board is correct.


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10.4 Intermittent OperationIntermittent problems are usually related to the environment in which the unit operates. For this reason the Sentry SR has been designed so that environmental problems can be distinguished from instrument problems with ease. The unit can also be tested locally, to eliminate any possible interference from the line or other equipment (page 65).

1. Check all external cabling, connections and associated equipment.

2. Check the serial output for error codes (Table 14, page 61).

3. Check that all heating and cooling equipment is functioning correctly.

4. Check that coolant is circulating through the cooling plate at the correct temperature, pressure and flow rate (page 21).

5. If the unit is sending invalid output, check that:• No dust, smoke, steam, rain or other environmental condition is interfering with a clear

line of sight between the unit and the material.• All windows and the sightglass (if provided) are clean.• The unit is programmed appropriately for its operating environment: window distance,

window time out, analog limits, first/last-pulse mode, fast/slow target dynamic.

6. If the analog output remains the same even when the range changes, check that the analog zero and maximum settings correspond to valid range readings (0-20 m). If the range differen-tial is small when compared to the analog span, readings may appear not to change. For example, if ranges vary from 10-11 m and analog settings are for 0-20 m, the analog output may appear fixed.


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10.5 Erratic, Fluctuating or Short ReadingsErratic or drifting range readings may be caused by interference between the rangefinder and the material, either from dust inside the enclosure or from atmospheric interference such as dust or rain. Such readings may also be the temporary result of a cold unit that is warm enough to fire, but is still warming up internally.

If your unit is producing erratic readings or ranges that are much shorter than expected, there may be a build-up of dust on the window. Especially in first-pulse mode, this may cause the unit to report a very short range reading to the enclosure window rather than to the target/material being measured.

1. If the unit is in last-pulse mode: Reprogram the unit to filtered last-pulse mode (page 33). This may eliminate interference from dust, rain or similar particles.

2. After a low-temperature start: Wait for about 15 minutes for the unit’s internal temperature to stabilize. Range accuracy will gradually improve over this period.


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10.6 Local TestIf you have followed the steps in the previous section and the problem persists, test the unit to a known, portable target such as a cardboard sign. Use a digital multimeter and keypad to test the analog and RS-232C serial output.

1. Reposition the Sentry SR and range it to the portable target.

2. Note the programmed analog limits, and then reprogram them temporarily to conform to the target range (page 31).

3. If desired, use the laser pointer to confirm that the laser beam is hitting the target. For laser pointer safety precautions, see page 3.

4. Check the range output locally on the analog and serial lines:

RS-232C serial Use keypad or similar device.Analog Use digital multimeter.

5. Move the target while monitoring the unit’s output.

6. Check that the serial and analog outputs ramp up smoothly.

7. If the range readings under test are:

Consistent The problem may be related to the operating environment. Go to Step 8.

Inconsistent Consult Optech.

8. Check all electrical interconnections and related equipment, and verify that there are no environmental obstacles such as dense dust and dirty windows.

9. Reprogram the unit with its original analog limits.

10. If the problem persists, contact Optech (page 58).

CAUTION Visible Laser Light - Do not Stare into BeamDo not point or install the unit at eye level where people may be working

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