User Manual

Weather Station Mast Type M2

M2-UM-4.0

Delta-T Devices Ltd

Notices Copyright All rights reserved. Under the copyright laws, this manual may not be copied, in whole or in part, without the written consent of Delta-T Devices Ltd. Under the law, copying includes translation into another language. Copyright © 2007 Delta-T Devices Limited Delta-T Devices Ltd reserves the right to change the designs and specifications of its products at any time without prior notice.

Author Nick Webb

Version M2-UM-4.0 Apr 07

Delta-T Devices Ltd Tel: +44 (0)1638 742922 130 Low Road, Burwell Fax: +44 (0)1638 743155 CAMBRIDGE CB25 0EJ e-mail: sales@delta-t.co.ukU.K. www: http://www.delta-t.co.uk

Contents

INTRODUCTION ............................................................2

GETTING STARTED......................................................3

IDENTIFICATION OF PARTS........................................4

INSTALLATION .............................................................7

M2 MAST SERVICING.................................................13

APPENDIX: FINDING TRUE NORTH..........................14

WARRANTY AND SERVICE .......................................15

Introduction

This manual describes how to assemble the M2 weather station mast. It can be used with a range of sensors including the WS-STD1 and WS-HP1 weather stations using the DL2e logger.

2 Introduction M2 User Manual v 4

Getting Started

This example assumes you are installing a weather station with a DL2e Logger 1. Unpack, identify the parts - see Identification of Parts, the Packing

List and check for damaged or missing parts. 2. Choose the location and prepare the site. 3. Erect mast with cross arms, brackets and sensors.

Install logger in canopy or optional M2 Enclosure. This step is as far as this M2 User Manual goes.

____________________________________________________________ 4. Wire up sensors – see the individual sensor manuals

(available on the Delta-T Software and Manuals CD). 5. Configure your Ls2Win logger program with your sensor types and

recording intervals - see your logger documents, listed below. 6. Check the sensor readings are sensible via the Ls2Win real-time view. 7. Start Logging.

Useful Documents The following documents may help. For DL2e loggers see: DL2e Quick Start Guide Ls2Win on line Help Using the Delta-T Weather Station with Ls2Win – (location Start,Programs,Ls2Win,Weather Station, Application Note) M2 Enclosure User Manual DL2e Hardware Reference For GP1 Loggers see: GP1 Quick Start Guide DeltaLINK on-line Help GP1 Weather Station Quick Start Guide GP1 Network Quick Start Guide GP1/DL6 GSM Modem System User Manual These documents and individual sensor user manuals are also available on the Delta-T Software and Manuals CD

M2 User Manual v 4 Getting Started 3

Identification of Parts

Figure 1: M2 Parts

4 Identification of Parts M2 User Manual v 4

24) M6 spacer (x4).

Parts Index 1) Mast upright

25) M6 washer (x4). 2) Cross arm. 26) M6 nut (x7). 3) Base plate. 27) Protective strip (x4). 4) Logger canopy. 28) Protective coil (x2). 5) Guy rope stakes (x4). 29) M8 nut. 6) Base plate stakes (x4). 30) Anemometer. 7) (Sensor rod - discontinued) 31) Windvane. 8) Level plate. 32) RH/air temperature sensor. 9) Mast/cross arm connector. 33) Solar radiation sensor. 10) Mast/base plate connector. 34) Delta Logger. 11) Mast/ball & socket

connector. 35) Bubble level. 36) Rain gauge base plate. 12) Ball & socket levelling

device. 37) Rain gauge ground stakes (x4). 13) Guy rope (x2). 38) Levelling studding (x3). 14) U bolt (x2). 39) M6 adjusting nuts (x6). 15) Guy rope tensioners (x4). 40) Spacers (x12). 16) D shackles (x4). 41) Rain gauge. 17) Saddle washers (x4). 42) Mallet. 18) End plugs (x2). 43) RH/air temp sensor mounting arm.

19) M10 x 40 bolt. 20) M10 spring washer.

44) V Bolts (x2), nuts & washers (x4) 21) M10 nut.

22) 1/4 inch BSW x 1.75 inch bolt (x2). 45) Adjustable Spanner.

46) Bubble level adjust spanner. 23) M6 x 12 bolt (x4).

M2 User Manual v 4 Identification of Parts 5

Description

Figure 2: WS-HP1 Figure 3: WS-STD1 plus RG2-M The M2 Weather Station Mast consists of a 2m high by 48 mm diameter anodised aluminium mast. Cross arm, connectors and fittings provide for mounting sensors and a DL2e Logger. The mast attaches to the ground via a pivot connected to a base-plate. This may be pinned to the ground by the stakes provided or bolted onto concrete or rock. This permits use of the mast on slopes and on hard or soft ground. A levelling mechanism ES-MOUNT fits on the top of the mast for mounting up to two solar radiation sensors of type ES2, QS2 or UV3. The cross arm M2-CA near the top of the mast supports an anemometer and a windvane. It is also used to attach the guy ropes. Below this can fit a bracket holding the combined air temperature and humidity sensor in a radiation shield. If your raingauge has a base-plate, stake it to the ground away from the mast. The RG1 base has a levelling mechanism. The RG2-BP does not. The RG2-M raingauge is mast mounted – as shown in Fig 3. The rim of all rain gauges should be horizontal. Additional protection may be provided by the DL2e Logger canopy WS-CAN or by the lockable enclosure of type M2-ENCL-B or M2-ENCL-M.

6 Identification of Parts M2 User Manual v 4

Installation

Choose the Location Results depend not just on sensor accuracy and reliability but also on how representative the site is – so choose the site carefully.

Where data is to be compared to a “standard” meteorological site, the sensors should be exposed in a similar way to sensors at the standard sites, i.e. over a level surface of short grass and away from trees or buildings.

These are rough guidelines. Refer to meteorological publications for further advice. e.g. http://www.wmo.int/web/www/IMOP/WebPortal-AWS/Index02.html

X

10 X

2 X

2 X

Clothes line effect

Oasis effect

Leading edge effect

Rules of thumb

Rules of thumb Near a building, mount the sensors outside the zone of influence. Horizontally this extends roughly twice the height of the building upstream and ten times downstream. Vertically it extends to about twice the height of the structure.

In other cases, where the requirement is to measure the true local conditions, e.g. a field of newly planted corn, select a relatively uniform area of the terrain. Be aware that, as a crop grows up towards the sensors, the measured wind speed decreases as the canopy approaches. Sensors will also be influenced by the changing local thermal and humidity microclimate above the crop.

Here we have no simple rules of thumb to follow – but be aware of the following:

M2 User Manual v 4 Installation 7

Clothes line effect: vegetation upwind may affect vapour gradients and heat transfer.

Oasis effect: If an isolated source of water, e.g. a lake or glacier, is surrounded by a relatively arid area then the relative humidity may be affected if the wind direction draws air from the water source.

Leading Edge effect: When air moves over the boundary between two surfaces that differ in temperature, moisture content, roughness or some other characteristic, it takes time for the air to adjust. The line of discontinuity is known as the leading edge. The boundary layer will vary in vertical extent with distance from the leading edge as it adjusts to the new conditions.

Gasometer effect: Avoid objects directly under the air humidity and temperature sensor, such as a solar panel, which can create a rising thermal plume when hot.

Mast Assembly and Erection It helps to have two people available.

1. Before assembly lay out all the parts and identify them: see Fig.1. 2. Slide the mast cross arm connector (9) over the mast upright (1)

and secure by tightening the Allen socket screw with the hexagonal 8 mm Allen key.

3. To minimise interference with the wind sensors mount the cross arm near the top of the mast.

4. Insert the cross arm (2) through the connector (9), centre it, and

align the holes vertically and secure it by tightening the Allen screw.

5. Screw the mast ball and socket connector (11) to the mast upright (1)

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6. Attach the solar energy sensor levelling device (12,,8,29 & 35) and screw it onto the mast ball and socket connector (11).

ES2

Ball jointBubble level

11

ES-MOUNT7. Attach the light sensor e.g. ES2. There is room for two radiation

sensors on plate (8). 8. Position the base-plate (3) so that the mast can be raised in the

desired direction. (If the land slopes steeply position the mast so that it lies up and down the slope

9. Pin the base plate (3) to the ground with the stakes provided, or bolt it down (bolts are not provided).

10. Find and mark where North lies. For highest precision find true north – to do this see the Appendix. For many users finding magnetic north (i.e. just with a compass) –will be good enough. Your actual requirement for precision depends, of course, on what you intend to do with the wind direction information. It is probably quicker to find true north than to debate the issue!

11. Place the stakes (5) in a rectangle around the base, equidistant from it and 2 to 3m from it, so that the guy ropes will be oriented at about 45 degrees to the north south direction. This will keep them out of the way of the Dl2 canopy..

On sloping ground try to position them so the forces on the mast are symmetrical.

M2 User Manual v 4 Installation 9

12. Orient the stakes so they present the maximum surface area to resist the pull of the guy ropes against the soil. Use the mallet provided to hammer them in the ground, leaving just enough room to attach the D shackles. If the soil is too light and sandy it may not grip the stakes strongly enough, in which case wedge them in with rocks or timber. Alternatively, on rock or concrete use expansion bolts with eyes, (not provided).

13. Feed the guy ropes (13) through the holes in the cross arm (2) as shown below. Ensure the loose ends are roughly of equal length.

14. Insert the base of the mast upright (1) into the base plate connector (10) and lay the mast down.

15. Feed each guy rope through a rope tensioner (15). At this point the rope tensioners should be fully loosened off. Attach to the stakes with a D shackle (16).

16. Raise the mast until vertical on the pivot. It is best to have one person do this and a second person to go round and take up the slack on the guy ropes. Tie them off under tension, with a round turn and two half hitches, or any reliable knot. At this point the mast should be self-supporting. Make any final rotational alignments to the mast and only then tighten up the Allen screw at the base of the mast.

17. Tighten up the rope tensioners (15) so the mast is vertical. Then tighten up the locking nuts to prevent them from unwinding.

18. Bolt the logger canopy to the mast using the two U bolts (14). These are supplied with a protective spiral plastic strip (28) and two strips of plastic channel (27).

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19. Mount the canopy, or optional M2 enclosure, at a convenient height. The canopy is designed to protect the logger from the heat of the sun, so mount it facing away from the equator (north in the northern hemisphere, on the south side in the southern hemisphere).

20. Remove the DL2e logger lid and insert the four M6 x 12 mm bolts to protrude out of the hole at the back of the logger. Hold these in with a screwdriver and bolt on the hexagonal rod spacers (24). The function of these spacers is to allow air currents to flow between the canopy and the back of the logger.

21. Replace the logger lid and bolt the logger to the canopy using four

M6 nuts (26) and washers (25).

22. The mast is now ready for the sensors! Install them as directed by your sensor user manuals

M2 User Manual v 4 Installation 11

Examples of installed sensors

AN1AN1 AN4AN1 WD1 WD4Refer to your individual sensor manuals for full installation instructions

Wind sensors Examples showing the use of saddle washers and bolts to mount wind sensors. Wind vanes should be oriented to face true north for highest accuracy – see Appendix

RG1 Raingauge levelling Levelling

mechanism Refer to the raingauge user manual for more information.

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M2 Mast Servicing

The mast itself should not require any maintenance. Periodically check that the soil has not moved and loosened the guy ropes (say every 6 months). To prevent corrosion spray the DL2e screw terminals with a water repellent silicon spray. Use of products like WD40 may cause the rubber buttons to come of the Klippon connectors, making them harder to remove. The hexagonal Allen socket screws are made of zinc-plated and passivated steel and will benefit from a coat of oil or grease. Grease the guy rope tensioners to protect the threads from rust. The mast and sensors are not designed to withstand salt spray corrosion.

Figure 4: Example of weather station sensors with mast type M2-MIN and enclosure type M-EMCL-B (with GSM modem) installed at Lochnagar, Scotland. Picture courtesy of Mike Hughes, Environmental Change Research Centre, University College, London

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Appendix: Finding True North

Compass Method Get a compass and the local angle of magnetic declination – either from a map, local airport - or use an online calculator e.g. http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcDeclination ...and enter your latitude and longitude.

Magnetic declination (or variation) is the angle between magnetic north and true north. It is positive when the angle measured is east of true north and negative when west. So, if the declination is positive, true north is left of magnetic north.

+30°

MAGNETIC NORTH = 360M

TRUENORTH= 0-30 = 270 M

TRUENORTH= 0-(-30)= 30 M

-30°

N

SE

WN

S

E

W

+ -PLUS MINUS

Example: How to find True North given a compass and the angle of magnetic declination

90

90

180 180

270

270

Typical map of magnetic declination for year 2000 (reproduced courtesy of NOAA)

Star Method Find the North Star or the Southern Cross and mark north on the horizon.

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Warranty and Service

Terms and Conditions of Sale Our Conditions of Sale (ref: COND: 1/00) set out Delta-T's legal obligations on these matters. The following paragraphs summarise Delta-T's position but reference should always be made to the exact terms of our Conditions of Sale, which will prevail over the following explanation. Delta-T warrants that the goods will be free from defects arising out of the materials used or poor workmanship for a period of twelve months from the date of delivery. Delta-T shall be under no liability in respect of any defect arising from fair wear and tear, and the warranty does not cover damage through misuse or inexpert servicing, or other circumstances beyond our control. If the buyer experiences problems with the goods they shall notify Delta-T (or Delta-T’s local distributor) as soon as they become aware of such problem. Delta-T may rectify the problem by replacing faulty parts free of charge, or by repairing the goods free of charge at Delta-T's premises in the UK, during the warranty period, If Delta-T requires that goods under warranty be returned to them from overseas for repair, Delta-T shall not be liable for the cost of carriage or for customs clearance in respect of such goods. However, we much prefer to have such returns discussed with us in advance, and we may, at our discretion, waive these charges. Delta-T shall not be liable to supply products free of charge or repair any goods where the products or goods in question have been discontinued or have become obsolete, although Delta-T will endeavour to remedy the buyer’s problem. Delta-T shall not be liable to the buyer for any consequential loss, damage or compensation whatsoever (whether caused by the negligence of the Delta-T, our employees or distributors or otherwise) which arise from the supply of the goods and/or services, or their use or resale by the buyer. Delta-T shall not be liable to the buyer by reason of any delay or failure to perform our obligations in relation to the goods and/or services, if the delay or failure was due to any cause beyond the Delta-T’s reasonable control.

M2 User Manual v 4 Warranty and Service 15

Service and Spares Users in countries that have a Delta-T Distributor or Technical Representative should contact them in the first instance. Spare parts for our own instruments can be supplied from our works. These can normally be despatched within a few working days of receiving an order. Spare parts and accessories for sensors or other products not manufactured by Delta-T, may have to be obtained from our supplier, and a certain amount of additional delay is inevitable. No goods or equipment should be returned to Delta-T without first obtaining the agreement of Delta-T or our distributor. On receipt at Delta-T, the goods will be inspected and the user informed of the likely cost and delay. We normally expect to complete repairs within a few working days of receiving the equipment. However, if the equipment has to be forwarded to our original supplier for specialist repairs or recalibration, additional delays of a few weeks may be expected.

Technical Support Technical Support is available on Delta-T products and systems. Users in countries that have a Delta-T Distributor or Technical Representative should contact them in the first instance. Technical Support questions received by Delta-T will be handled by our Tech Support team. Your initial enquiry will be acknowledged immediately with a “T number” and an estimate of time for a detailed reply (normally a few working days). Make sure to quote our T number subsequently so that we can easily trace any earlier correspondence. In your enquiry, always quote instrument serial numbers, software version numbers, and the approximate date and source of purchase where these are relevant.

Contact details: Tech Support Team Delta-T Devices Ltd 130 Low Road, Burwell, Cambridge CB25 0EJ, U.K. email: tech.support@delta-t.co.uk Web site: www.delta-t.co.uk Tel: +44 (0) 1638 742922 Fax: +44 (0) 1638 743155

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