Download - Scada Hardware Manual
-
8/8/2019 Scada Hardware Manual
1/99
meritHARDWARE MANUAL
TABLE OF CONTENTS
1.0 Introduction
1.1 Organization of the Manual
1.2 Who will get the best out of this manual
2.0 Overview of Traction Power Distribution
3.0 Overview of the Scada System
3.1 Remote Control Centre
3.2 Location of RCC equipment
3.3 Remote Terminal Unit ( RTU )
4.0 Functional Description of the SCADA System
4.1 General
4.2 Remote Control Centre
4.3 Remote Terminal Unit
5.0 Technical description of Remote Terminal Unit
5.1 General
5.2 RTU at Traction Sub-station
5.3 RTU at sectioning and paralleling post
5.4 RTU at sub-sectioning and paralleling post
5.5 Functional description of Remote terminal Unit
5.5.1.0 Logic chassis
5.5.1.1 CPU module
5.5.1.1.1 Watch dog Timer
5.5.1.1.2 Interrupt Logic
5.5.1.1.3 Address Latch
5.5.1.1.6 Memory
5.5.1.2.0 Digital Output Module ( DOM )
5.5.1.2.1 Functional Description of DOM
5.5.1.2.2 Select Before Operation and Description
5.5.1.3.0. Digital Input Module ( DIM )
5.5.1.3.1 Interface Connection and Functional Description
Page No : 1
-
8/8/2019 Scada Hardware Manual
2/99
meritHARDWARE MANUAL
5.5.1.4.0 Analog Input Module ( POWER METER )
5.5.1.4.1 Functional Description of POWER METER
5.5.2.0 Interface Card Enclosure
5.5.2.4 Catanery Interface ( CIC )5.5.3.0 Modem
5.5.3.1 Overview of Modem
5.5.4.0 Power Supply Unit
5.5.4.1 Principle of Operation
5.5.4.2 Protection Features
5.5.4.2.1 Mains Supervision
5.5.4.2.2 Battery Supervision
5.5.4.3 Functional Description of LDA75F5.5.4.4 Functional Description of LDC30F
5.5.4.5 Overcurrent Protection
5.5.4.6 Overvoltage Protection
5.5.4.7 FoldBack Characteristics
5.5.6.0 Contactors / Relays
5.5.7.0 Terminal Block
5.6.0 Description of Telemetry at TSS
5.6.1 Under Voltage Tripping of Bridging Interruptors5.6.2 Scheme of Telemetry at SP
5.6.3 Scheme of Catenary Indication at SP
5.6.4 Closing of Bridging Interruptors
5.6.5 Under Voltage Tripping of Interruptors
5.6.6 Sequence of Operations of Under Voltage Tripping
5.6.7 Catenary Voltage Sensing at TSS
5.6.8 Scheme of Telemetry at TSS
5.6.9 Auto Re-closing Scheme at TSS
5.6.10 Field Wiring
Page No : 2
-
8/8/2019 Scada Hardware Manual
3/99
meritHARDWARE MANUAL
6.0 Maintenance of SCADA System
6.1 Maintenance philosophy
6.2 RTU Power Supply Unit
6.4 Table of Periodic Inspection and Maintenance6.5 Fault Finding and Rectification
6.6 Testing Equipment Requirement
6.7 Test Equipment
7.0 RTU Trouble Shooting Procedure
7.1 TeleSignal
7.2 Telemetry
7.3 Telecommand
7.4 Power supply Unit7.5 Trouble Shooting Chart for UPS
7.6 Trouble Shooting Procedure for Modem
7.7 TeleSignal Fault Finding Chart
7.8 TeleMetry Fault Finding Chart
7.9 TeleCommand Fault finding Chart
8.0 Downloading Program To Rtu Micro controller
9.0 Download Parameters to RTU
9.1 Testing the various parameters using MERITDIAG:
Page No : 3
-
8/8/2019 Scada Hardware Manual
4/99
meritHARDWARE MANUAL
CHAPTER - 1
1.0 INTRODUCTION
1.1 ORGANISATION OF THIS MANUAL
This document is the hardware manual of Remote Terminal Unit for Supervisory Control
and Data Acquisition (SCADA) System designed, manufactured and supplied by M/s
MERIT, Chennai. It contains the technical description, user procedures and maintenance
aspects of the system.
This manual helps the user to correctly install the system , use it effectively and maintain
properly.
The manual starts with an overview of traction distribution network and briefly introduces the
user to the SCADA system. Then the manual gives the technical description of the system
and the associated sub-systems. Finally, it deals with the maintenance aspects.
1.2 Who will get the best out of this manual ?
This manual is prepared for the use of the technical persons who are involved in using the
system and those who have the responsibility for maintaining it. The details contained in
this manual are highly technical in nature and hence the reader is expected to have a
basic understanding of electronics circuits and exposure to the latest state of art
technology.
The manual only covers basic trouble-shooting procedures and techniques. The reader is
advised to contact the technically trained engineers of SCADA system, before embarking
on component changes.
Page No : 4
-
8/8/2019 Scada Hardware Manual
5/99
meritHARDWARE MANUAL
CHAPTER - 2
2.0 OVERVIEW OF TRACTION POWER DISTRIBUTION
25KV AC, 50 Hz Single phase electric traction system is adopted for the electrified tracks.
Power is obtained from State Electricity Boards (SEBs) from their network at
220/132/110/66 KV at traction substations (TSS) and stepped down to 25 KV.
The high voltage winding of the single phase transformer is connected across two phases
and one terminal of the 25KV winding is connected to the rail and the other terminal to the
catenary system (Over Head Equipment (OHE)). The TSSs are spaced at a distance of
40 to 60 km.
The supply to the OHE from TSS is fed through interrupters located at feeding post (FP).
Adjacent TSSs normally supply power to the OHE on different phases to reduce
unbalance in the supply authorities grid.
To avoid the pantograph of a locomotive or electric multiple unit from bridging the supply
from different phases when it passes from one zone to another, a neutral section is
provided to separate the OHEs fed from different phases. The switching station provided
at neutral section is called "Sectioning and Paralleling post" (SP). At the SP in multi track
sections, the OHEs are also paralleled independently on either side of the neutral section
to reduce voltage drop. In an emergency, when a TSS is out of commission, feed from
adjacent TSSs on either side is extended up to the failed TSS by closing interrupters at
SP. The pantograph(s) of locomotive(s) or electric multiple unit is (are) lowered at the
failed TSS to avoid short circuiting the phases at the insulated overlap.
Between a TSS and adjacent neutral section, the OHE is divided into sub-sections for
isolating the faulty section for the purpose of maintenance and repairs.
The switching stations provided at such points are called "Sub-sectioning and paralleling
posts (SSP). The OHE of various tracks, in multiple track sections, are also paralleled at
the SSP to reduce voltage drop in OHE. The sub-sectors are further divided into
elementary sections by the use of manually operated isolators.
Page No : 5
-
8/8/2019 Scada Hardware Manual
6/99
meritHARDWARE MANUAL
At TSS, SP and SSP, equipment like power transformers, circuit breakers, interrupters,
single and double pole isolators, potential and current transformers, lightning arrestors, LT
supply transformers etc., are installed in a fenced enclosure which is locked up. A
masonry building is provided for housing the control panels, SCADA equipment, batteryand battery chargers, telephones and others.
All traction substations are manned and switching stations are normally unmanned. The
devices that are controlled from RCC through the SCADA equipment are circuit breakers,
interrupters and transformer tap changers. The tap changer of the transformer, circuit
breakers and interrupters can also be operated locally at the TSS, SP and SSP as the
case may be.
At the TSS, a local / remote changeover switch is provided on the control panel, as well as
in the mechanism box of the circuit breaker, interrupter and motor operated isolators. No
control panel exists for the interrupters at the SP and SSP and therefore the local / remote
changeover switch is provided on the mechanism box of the interrupter.
Page No : 6
-
8/8/2019 Scada Hardware Manual
7/99
meritHARDWARE MANUAL
CHAPTER 3
3.0 OVERVIEW OF THE SCADA SYSTEM
The SCADA system is designed to monitor the status and control of the 25KV electrified
traction system. It is a fully integrated hardware and software system with a central control
to monitor and control the field devices located at remote sites.
The SCADA system can be classified into two broad categories:
1. Remote Control Centre (RCC)
2. Remote Terminal Unit (RTU)
3.1 Remote Control Centre
RCC is designed for monitoring different types of data like catenary indication, device statusand telemetry from various control stations. It also controls the field equipment like circuit
breakers, bridging interrupters, transformer tap position changing etc., RCC stores the
data regarding alarms, events, and telemetry to help the user to analyse the status of the
overhead equipment and switching stations. This data can be used for maintenance
purposes also. For example, RCC helps the user to easily identify the fault in OHE located
in various sections, for immediate rectification.
RCC consists of the following equipment:
a) Main and standby Computerb) Operator Workstation computer
c) Communication Processors with Modems
d) Printer and Print Sharer Switch
e) Modem
f)UPS
g) Battery
3.2 Location of RCC equipment
These equipments are located in Traction Power Control (TPC) room. The UPS and
batteries are located in the UPS room and batteries room respectively. Main and Standby
Computers, Communication Processors, Modems Workstation Computers and Printers
are installed in the TPC Room. Supervisory console is installed at CTPC Room.
Page No : 7
-
8/8/2019 Scada Hardware Manual
8/99
meritHARDWARE MANUAL
System configuration
Page No : 8
-
8/8/2019 Scada Hardware Manual
9/99
meritHARDWARE MANUAL
3.3 Remote Terminal Unit (RTU) DESIGN AND MANUFACTURE BY M/S SANMAR
RTU is designed to control and monitor field equipment. It accepts digital and analog input
signals from the remote field equipment. It receives the control commands from the RCC.
RTU can be divided into the following four parts:
a) Logic Chassis
b) Interface Unit
c) Energy Meter
d) Modem
RTU accepts digital and analog input signals from the remote locations (TSS/SP/SSP) and
receives the control command from the RCC to perform the following tasks :
* Status input monitoring and change of status
* Control output operation
* Analog input monitoring
* Communication with RCC
RTU is designed to be flexible, modular and reliable making it easy to maintain and expand.
A highly integrated microprocessor based system, coupled with firmware programming
allows the RTU to perform sophisticated control and data acquisition functions.
RTU system can be configured for a wide variety of I/O mix, which can be configured and
expanded as required in the field. The configuration of an RTU is stored in non-volatile
memory and may be edited or expanded without hardware changes.
The RTU provides the following basic data acquisition functions:
* Data acquisition for status input and analog input
* Control outputs
* RTU / Master station communications
Implementation of the RTU capabilities is a combination of hardware logic and firmware
logic that is stored in Read Only Memory (ROM). This provides a convenient means to
alter and / or extend the capabilities of the RTU without significant hardware modification.
Page No : 9
-
8/8/2019 Scada Hardware Manual
10/99
meritHARDWARE MANUAL
Each TSS RTU will support,
* up to ninety six (96 ) Digital Input points
* up to Fourty Eight (48 ) Digital Output Points
* up to sixty four (8 ) analog input Points
Page No : 10
-
8/8/2019 Scada Hardware Manual
11/99
meritHARDWARE MANUAL
CHAPTER 4
4.0 FUNCTIONAL DESCRIPTION OF SCADA SYSTEM
4.1 General
The SCADA System, from RCC enables the Traction Power Controller (TPC) to control the
25 KV traction power supply to OHE. It also monitors and operates various equipments at
traction sub stations located enroute.
The SCADA System for Traction Power Control consists of two major parts:
a) Main and Standby Computers, Work station computers, Communication processors
are connected in the LAN set up and Powered through UPS with battery back up at
RCC
b) Remote Terminal Units (RTU) for acquisition of field parameters from the unmanned
control stations along the traction network.
The RCC and RTUs are connected in Wide Area Network (WAN).
The RCC Computers communicate with each RTU in a predefined sequence over the WAN
to acquire information regarding;
* Status of CB, interrupter, relays etc.
* Alarm condition in the controlled station
Measurand values
4.2 Remote Control Centre
The Main and Standby Computers are Server Grade Pentium IV with 15" color monitor.The Main computer interacts between the Communication processor and Workstation
computers. It collects the formatted RTU information from Communication processor and
sends the processed information to the Operating Workstation (OWS) computers, which
enables the user to understand the field conditions.
The Main computer also responds to the requests of the OWS computer, which receives
commands from Traction power controller. Then, this information will be formatted and
sent to the communication processor.
The Main computer also updates available information with the slave computer, which
should have the same information. Whenever the Main computer fails, then the Slave will
become Main with updated information.
The Communication Processors (CP) are Server Grade Pentium IV Computers.
The Workstation Computers are Server Grade Pentium IIV with 21" color monitor
Page No : 11
-
8/8/2019 Scada Hardware Manual
12/99
meritHARDWARE MANUAL
4.3 Remote Terminal Unit (RTU)
RTU accepts digital and analog input signals, from the remote locations, TSS, SP and SSP.
It receives the control signals from the RCC. It performs the following tasks:
* Input status monitoring and recording the change of status
* Control output operation
* Analog input monitoring
* Communication with RCC
RTU consists of the following five parts, namely (not shown in the block diagram),
* Power Supply Unit
* Logic Chassis
* Interface Unit
* Modem
* Termination Section
Power Supply unit Consists of two Parts, one for main 24V dc supply and the other is
(5v, 12v, -12v) for Modem and Interface card reference supply.
The Logic Chassis is the main part of RTU, and is based on microprocessor. It is used to
control and process all field signals. Each Logic Chassis supports 96 digital input, 48
digital output signals, 8 analog input signals.
The Interface Unit receives and controls the field signal devices. Energy Meter that is part
of the Interface Unit is used to convert the field analog signals like voltage and current.
Modem is used to convert the digital information to analog information suitable to for four
wire based communication cable and vice-versa in the FSK & PSK mode.
Termination Section is used to interconnect the field cables and RTU internal cables to
perform the control and supervisory operation at the field.
CHAPTER - 5
Page No : 12
-
8/8/2019 Scada Hardware Manual
13/99
meritHARDWARE MANUAL
5.0 TECHNICAL DESCRIPTION OF REMOTE TERMINAL UNIT
5.1 GENERAL
The Remote Terminal Unit (RTU) acts as the common interface between the field devices
and the Remote Control Centre of the system. The Remote Terminal Unit is designed
to be flexible, modular and reliable, making it easy to maintain and easy to expand. It is
highly integrated microprocessor based logic system, coupled with firmware
programming, which allows the Remote Terminal Unit to perform sophisticated control
and data acquisition functions.
RTU accepts digital and analog input signals from the Remote locations (TSS / SP / SSP)
and receives the Control command from the RCC to perform the following tasks:
* Status input monitoring and change of status
* Control Output operation
* Analog Input monitoring
* Communication with RCC
5.2 RTU AT TRACTION SUB-STATION - TSS
This RTU is designed for the following capacity:
* 24 Telecommands
* 48 Telesignals
* 06 Telemetries
The term Tele command is used in railways to give output and sense the status feedback
for the particular device. Generally each Telecommand represents two digital outputs
and corresponding two digital inputs.
Page No : 13
-
8/8/2019 Scada Hardware Manual
14/99
meritHARDWARE MANUAL
RTU Block Diagram
The following are the Telecommands available in the TSS RTU:
1. 132 KV Circuit Breakers - 02
Page No : 14
-
8/8/2019 Scada Hardware Manual
15/99
meritHARDWARE MANUAL
2. 25 KV Circuit Breakers - 05
3. 25 KV Interrupters - 05
4. Auto Re-closure - 02
5. Tr. Tap Changer - 026. Interlock release - 01
The scheme of operating the sl.no.1, 2 & 3 is shown in the figure. This requires close and
open operations from the RTU and monitoring the status.
Auto reclosure is the facility available in the field. TSS control panel to close the feeder CB
automatically once whenever the CB trips and the scheme will become locked out
condition. The RTU is to sense the locked out signal and command is to be given to
release / reset the lock out.
Transformer, which is stepping down 132 KV to 30 KV, is having six steps of tapping
position. This TAP POSITION may be raised or lowered by giving RAISE or LOWER
commands and status of TAP POSITION (any one out of six) is to be monitored.
The following are the Telesignals to be sensed at TSS:
TYPE I Telesignals
* Transformer alarm - 2 nos
* Transformer fault - 2 nos
* Transformer Tap position - 12 nos
* 110V DC Fail for Tr. Trip - 2 nos
* 110V DC Fail for Tr. Alarm - 1 no
* W.P.C / D.P.R / O.C.R relay (FCB I) - 3 nos
* W.P.C / D.P.R / O.C.R relay (FCB II) - 3 nos
Using 110V DC from the field senses the above alarms.
Page No : 15
-
8/8/2019 Scada Hardware Manual
16/99
meritHARDWARE MANUAL
Block diagram of tss
Page No : 16
-
8/8/2019 Scada Hardware Manual
17/99
meritHARDWARE MANUAL
General scheme of TSS wiring
Page No : 17
-
8/8/2019 Scada Hardware Manual
18/99
meritHARDWARE MANUAL
Tss wiring 2 of 2
Page No : 18
-
8/8/2019 Scada Hardware Manual
19/99
meritHARDWARE MANUAL
G.A DIAGRAM OF TSS
TYPE II Telesignals
* 240V AC failure / PSU on DC - 1 no
* 25 KV feeder PT Fuse fail - 2 no
* Tr. Line Pt Fuse fail - 1 no
* 25 KV Shunt Cap. PT fuse fail - 1 no
In the above alarms are sensed by using availability of 240V AC and 110V AC from the
field.
TYPE III Telesignals
* 110V DC Low - 1 no
Page No : 19
-
8/8/2019 Scada Hardware Manual
20/99
meritHARDWARE MANUAL
In the above alarms are sensed by using availability of 110V DC from field batteries.
TYPE IV Telesignals
* Catenary indication - 4 nos.
In the above alarms are sensed by the availability of 120V AC from PTs connected to the
Overhead equipment.
The term Telemetry is used in railways to measure the current, voltage and Maximum
demand from the field. Each Telemetry will have one analog input from the field.
Voltage
Current
Maximum demand
Voltage is measured from the 25 KV / 110 V Pts and Voltage changeover scheme connects
the higher side of the PT voltage to the Transducer.
Current is measured from the CTs whose ratings are given below
The Accuracy of the Voltage, Current, PF and MD is Class A Type (ie, 0.5%).
Dead Band : 0 to 255 ( 1 byte)
Resolution : 10 Bit
Normal value : 1000 Units.
Value of the LSB bit : 10 mv
(Resolution )
For 25 KV side
Primary side - Secondary side
1000A or 500A - 5A
1500A or 750A - 5A
For 132 KV side
Primary side - Secondary side
100A or 200A - 5A
The secondary side will be connected to the Energy Meter through Shorting terminals.
Page No : 20
-
8/8/2019 Scada Hardware Manual
21/99
meritHARDWARE MANUAL
Maximum demand is the parameter calculated from the measured Voltage and Current.
This will be done in the software at the Remote Control Center.
5.3 RTU AT SECTIONING AND PARALLELING POST - SP
The following is the design capacity of SP RTU :
Telecommands - 8 nos
Telesignals - 12 nos
Telemetry - 4 nos
The following are the Telecommands available in the SP RTU
25 KV interrupter - 4 nos
Spare - 4 nos
In general ,SP will have two nos of parallel interrupters which could be operated by issuing
open and close commands and another two nos of bridging interrupters which have to
meet the following Under voltage trip conditions :
Under-voltage Tripping
Under voltage tripping is the facility provided for bridging interrupters of SP. The two
different phases of 25 KV voltage are fed from the adjacent TSS to the Bridginginterrupter and it should not be closed when both sides of the voltages are high.
Whenever one side TSS fails, then RTU is able to close the Bridging interrupters to
extend the feed from one side to another side. After extending the feed, if both side
voltages are going low, then RTU should trip the bridging interrupters.
The following are the Telesignals to be sensed at SP :
TYPE I Telesignals
* Spare - 4 nos
The above alarms are sensed by the availability of 110V DC from the field.
TYPE II Telesignals
* 240V AC failure / PSU on DC - 1 no
* Spare - 1 no
Page No : 21
-
8/8/2019 Scada Hardware Manual
22/99
meritHARDWARE MANUAL
In the above alarms are sensed by the availability of 240V AC.
TYPE III Telesignals
* 110V DC Low - 1 no
* Spare - 1 no
In the above alarms are sensed by the availability of 110V DC from field batteries.
TYPE IV Telesignals
* Catenary Indication - 4 nos
(Inclusive of Under voltage tripping facility)
In the above alarms are sensed by the availability of 120V AC from PTs connected to the
Overhead equipment.
Block diagram of sp & ssp
Page No : 22
-
8/8/2019 Scada Hardware Manual
23/99
meritHARDWARE MANUAL
General scheme of sp/ssp wiring
Page No : 23
-
8/8/2019 Scada Hardware Manual
24/99
meritHARDWARE MANUAL
General scheme of sp / ssp wiring 2 of 2
Page No : 24
-
8/8/2019 Scada Hardware Manual
25/99
meritHARDWARE MANUAL
G.A DIAGRAM OF SP /SSP
Page No : 25
-
8/8/2019 Scada Hardware Manual
26/99
meritHARDWARE MANUAL
TELEMETRY
In SP, voltage is measured from the up and down line 30 KV / 120V PTs where thesecondary voltage of the PT is connected to the Energy Meter.
5.4 RTU AT SUB-SECTIONING AND PARALLELING POST - SSP
The following is the design capacity of SSP RTU :
Telecommands - 8 nos
Telesignals - 12 nos
Telemeter - 4 nos *
( * The above 4no Telemeters are spare. Hence Transducers will not be provided in the
RTU)
The following are the Telecommands available in the SSP RTU :
25 KV interrupter - 3 nos
Spare - 5 nos
The following are the Telesignals are to be sensed at SSP :
TYPE I Telesignals
* Spare - 8 nos
The above alarms are sensed by using availability of 110V DC from the field.
TYPE II Telesignals
* 240V AC failure / PSU on DC - 1 no
* Spare - 1 no
The above alarms are sensed by using availability of 240V AC.
TYPE III Telesignals
Page No : 26
-
8/8/2019 Scada Hardware Manual
27/99
meritHARDWARE MANUAL
* 110V DC Low - 1 no
* Spare - 1 no
The above alarms are sensed by using availability of 110V DC from the field batteries.
TYPE IV Telesignals ( Subject to the requirement )
* Catenary indication - 4 nos.
The above alarms are sensed by using availability of 120V AC from PTs connected to the
overhead equipment.
5.5 Functional Description of Remote Terminal Unit
Remote Terminal Unit is comprised of the following modular blocks
a) Logic Chassis
b) Interface Unit
c) Modem
d) Power Supply Unit
e) Transducer
f) Contactors / Relays
g) Terminal Block
Page No : 27
-
8/8/2019 Scada Hardware Manual
28/99
meritHARDWARE MANUAL
Signal flow diagram
5.5.1.0 Logic Chassis
A highly integrated microprocessor based logic system, coupled with firmware
programming, allows Logic Chassis to perform sophisticated control and data acquisition
functions. The Logic Chassis can be configured for a wide variety of I/O mix which can
be configured and expanded as required in the field. The configuration of an Logic
Chassis is stored in non-volatile memory and may be edited or expanded without
hardware changes
Page No : 28
-
8/8/2019 Scada Hardware Manual
29/99
-
8/8/2019 Scada Hardware Manual
30/99
meritHARDWARE MANUAL
Block diagram of logic chasis
5.5.1.1 CPU Module
CPU Module acts as the backbone to Logic Chassis. It is based on the microcontroller
Technology Philips micro-controller 80C669. The 80C669 is a highly integrated 16 bit
device with 33MHz speed which implements the following on-chip features
* Serial communication:
Page No : 30
-
8/8/2019 Scada Hardware Manual
31/99
meritHARDWARE MANUAL
In build in CPU and can support up to two serial ports on the
designed baud rate
* Number of DI, DO and AI can handle by a single CPU:
Digital Input and Digital Output: Maximum 1536
Analog input: Maximum 8
* Up to 16 Mbytes linear address space
* Five programmable chip selects
* Maximum of 56 interrupts
Block diagram of CPU
Page No : 31
-
8/8/2019 Scada Hardware Manual
32/99
meritHARDWARE MANUAL
Functional block diagram of CPU
These features combined with 33 MHz processor clock to perform many sophisticated
Page No : 32
-
8/8/2019 Scada Hardware Manual
33/99
meritHARDWARE MANUAL
data acquisition and control functions as software tasks. It contains the following function
blocks
* Watchdog timer
* Interrupt Logic
* Address Latch
* Modules Select Logic
* Module Address Data Bus
* Flash EPROM and RAM
* Dip Switches to set the address of Node
LED Indications
To display the operating status, the CPU module have four LED indications
INDICATION FUNCTION
PWR Supply Voltage Monitor
RUN CPU status and error display
TXI TX Status OF COM1
RXI RX Status OF COM1
TX2 TX Status OF COM2
RX2 RX Status OF COM2
Red ON Supply Voltage < 17V dc and Low
Battery
Details of RUN LED
LED STATUS MEANING
OFF Controller stopped / Fault
Page No : 33
-
8/8/2019 Scada Hardware Manual
34/99
meritHARDWARE MANUAL
Green blinking Controller Running
5.5.1.1.1 Watchdog Timer
The inbuilt function of the Micro controller monitors three vital conditions for the
Microcontroller, power supply and external reset.
First, a precision temperature compensated reference and comparator circuit is used to
monitor the status of +5V (VCC) power supply. When VCC falls below 4.65 V, the Chip
forces reset to the active state. When VCC returns to normal, i.e. greater than 4.65V,
then the reset signal is kept active for a minimum of 250ms to allow the power supply
and processor to stabilize. It has also additional feature of write protection for CMOSRAM or EPROM.
The watchdog timer continuously monitors the process of Microprocessor. The Watchdog
accomplishes this by activating the reset line, if the strobe input is not driven low before
the chips internal 500 ms timer has timed out. The strobe input is derived from the
microprocessor timer / counter output (TCO) which must be set from the software. If the
software does not reset the timer counter within the allotted time, a strobe pulse is not
generated and the reset line is forced to the active state. The reset is held momentarily
and then released, which causes the RTU to reinitialize and start execution from the
restart vector.
5.5.1.1.2 Interrupt Logic
The Logic Chassis is a real time device and therefore fully utilizes interrupts. There are two
external hardware sources from which an interrupt can originate. The first is initiated
when a change occurs at a status input. Status input modules contain the logic which
generate a signal any time their input values are changed, these signals are then sent toCPU and are input at data latches.
It should be noted that only odd numbered COS lines are input to data latch this is
because the even numbered modules pass their interrupts along to the odd numbered
Page No : 34
-
8/8/2019 Scada Hardware Manual
35/99
meritHARDWARE MANUAL
modules using the dedicated COS and COMPEN lines on the MOD bus and the odds in
turn pass the COS to data latch.
An active COS signal at the inputs to data latch acts to generate an active state at its output
and in turn at the 80C167C interrupt input. When the processor receives an interrupt, it
immediately enters service routine, which reads latch to determine which pair of Status
inputs signals (COS), caused the interrupt. Once the pair has been determined, the
processor reads the indicated module pair to determine the specific input or inputs, which
have changed.
5.5.1.1.3 Address Latch
The 89C669 utilizes a multiplexed Address data bus; therefore it is necessary to de
multiplex or latch the address information. The Address latch is comprised of D type
latches whose outputs are always enabled and clocked by the ALE (Address Latch
Enable) signal
5.5.1.1.6 Memory
The Memory is divided into 3 types
Processor RAM
External RAM
Processor RAM of 2KB is made available to the processor module to store the non-
alterable storage of program code. The ram may be accessed through 16bit word or Byte
segments.
Flash RAM (128 KB) is used by the RTU to store configuration variables and system
data, which require memory to be non-volatile, yet alterable without hardware changes or
replacement.
RAM (256KB) is used as a general-purpose area for the microcontroller to store data,
variables and operating information that are temporary in nature. Information stored in
this section area is volatile and will be lost in the event that power is removed from the
Logic Chassis. These devices also word are byte accessed using the select logic
provided by the processor control lines.
5.5.1.2.0 Digital output Module (DOM)
The Control output system for the RTU comprised of two basic types of components,
Page No : 35
-
8/8/2019 Scada Hardware Manual
36/99
meritHARDWARE MANUAL
control function modules (DOM) that are added in the Din rail and attached with the CPU
module to interface with the field equipments through potential free contactors. The
Digital output module (DOM) contains the logic and CPU interfaces hardware.
Each Digital output Module (DOT) has sixteen outputs and is designed to drive the
Contactors of 10A rate, which in turn activate the field equipments. These modules could
be plugged into the Din rail as and when required.
5.5.1.2.1 Functional Description of DOM
The Digital output function module (DOM) is comprised of group of data latches, which
act together write-read-execute sequence logic to provide secure control operations. All
control output operations are initiated and monitored by CPU module. A control operation
begins when CPU places a bit pattern and simultaneously strobe the new value into the
data latch of the Digital output module. Next the CPU reads back the data, verifies it by
strobing the data and reads back to latch. If the read data and already sent data are
same then the CPU issues an execute pulse to drive the Each module provides 8 digital
outputs at the rate of 24Vdc / 0.1 A and the Module requires the power supply is from
+18V to +30V dc with the power consumption of 200mW. Respective LEDs of Orange
color indicates present state of output signal. The Output from the Opto - isolator
operate the contactors.
Page No : 36
-
8/8/2019 Scada Hardware Manual
37/99
meritHARDWARE MANUAL
Connection details of dot
Page No : 37
-
8/8/2019 Scada Hardware Manual
38/99
meritHARDWARE MANUAL
Block Diagram of DOT
5.5.1.2.2 SBO ( Select Before Operation) Operation and Description :
1. Request: Selection Command
Whenever activation is enabled in Select Command packet, the selected digital
output point read by the CPU and simultaneously strobe the new data output point
into the data latch of the Digital output module.
2. Response: Select Confirmation
Once receiving the Select Command from RCC, the CPU module reads back the
data from data latch of DOT and compare the bit pattern of the digital output value. If
Page No : 38
-
8/8/2019 Scada Hardware Manual
39/99
meritHARDWARE MANUAL
bit pattern are matching and CPU sends the Selection Confirmation to RCC and If
RCC decides to cancel the selection, then the Select command is sent with a
deactivation and the CPU will disable the data latch value.
3. Request: Execute Command
Once RCC gets the Selection confirmation then it transmits the command message
with Execution packet. After getting the execution command, the CPU enables the
output channel in DOT that was already selected by the selection command. The
digital output channel enable time duration depend upon qualifier bit (10 ms to 2.55
Seconds (in single command record. The default enable time is one second.
4. Request: Execute Confirmation
Once the CPU executes the command and enable the selected digital output
channel, then the RTU responds with an activation termination to RCC to indicate
that the command has been successfully issued.
Page No : 39
-
8/8/2019 Scada Hardware Manual
40/99
meritHARDWARE MANUAL
Connection details of DIT
BLOCK DIAGRAM OF DIT
Page No : 40
-
8/8/2019 Scada Hardware Manual
41/99
meritHARDWARE MANUAL
5.5.1.3.0 Digital Input Module (DIM)
Each Digital input module has eight inputs and is designed to provide input points of
status information to the CPU module from the Input interface cards.
5.5.1.3.1 Interface Connection and Function Description
The Digital input Module (DIM) accepts the inputs from the field (110v DC) , the 16
Inputs and the which are multiplexed and Transferred to CPU. All the four inputs areelectrically isolated from the logic circuitry of the module and connected through terminal
block for input with reference to common 0V connection.
Basic circuit of Digital input module is shown. It describes the process of the input signal
with isolation and the LEDs connected to show the status of each signal. The modules
are designed for signal voltages up to 110V dc and used to collect the binary control
signals from the system and transmit them to the CPU. It may be easily exchanged in the
working condition without disconnecting the individual wire. Individual Green LEDs are
used to show the status of the system and the maximum power consumption is 100mW.
5.5.1.4.0 Analog Input module (AIT) POWER METER
The system comprises of a single 8 channel Analog input module with necessary Inbuilt
Page No : 41
-
8/8/2019 Scada Hardware Manual
42/99
meritHARDWARE MANUAL
Transducers. The Analog input module fixed in the Din rail and the system uses
multiplexing method which selects a specific termination channel read by the A to D
converter. The channels are read sequentially starting with channel 1 and proceeding to
the last channel configured in the system.
CONNECTION DETAILS OF AIT
Page No : 42
-
8/8/2019 Scada Hardware Manual
43/99
meritHARDWARE MANUAL
BLOCK DIAGRAM OF AIT
Page No : 43
-
8/8/2019 Scada Hardware Manual
44/99
meritHARDWARE MANUAL
The Analog input module accepts PT Voltage and Feeder Current and converts them to
proportional digital values. The module contains A to D converter, reference sources,
signal conditioning and multiplexing hardware required to select the correct signals from
the field. In this module we have the features to select the type of input is voltage orcurrent is based on the DIPswitch present at the backside of the module.
5.5.1.4.1 Functional Description of Power Meter
The Analog input values are received from the field in the form of PT voltage and Feeder
current. All the input channels are led to a common multiplexer and are galvanically
isolated. The time-multiplexed voltage is fed to the instrumentation amplifier where the
signal is converted from a differential mode to single ended signal. Analog source selectswitch is used to select between the +reference, - reference, ground or multiplexed field
inputs. The output of the power meter is been transmitted to the CPU module through
serial data bus.
.5.2.0 INTERFACE CARD ENCLOSURE
Interface card enclosure consists CIC INTERFACE to Monitor the Status Of
Catenary Input Signals
5.5.2.4 Catnery Interface Module ( CIC )
Page No : 44
-
8/8/2019 Scada Hardware Manual
45/99
meritHARDWARE MANUAL
The catenary indication, which is available in the range of 0-120V AC, from the field (25KV /
100V AC PT) is sensed using this circuit. This catenary indication is sensed with various
ranges to eliminate the effect of induced voltage from the adjacent OHE when the
sensing OHE is dead. The comparator circuits have been provided with potentiometerto adjust the drop-off and pickup of the relay as described below:
The 0-100V AC from PT is fed as an input to the Transformer. An MOV is provided across
this input to act as a surge arrestor. The stepped down output from the Transformer is
rectified through bridge rectifier and filtered of transients with capacitance filter C. The
interface supply (12V DC) is connected to this circuit for functioning of ICs and Relays
and same voltage is adjusted for comparator input reference voltage.
Two numbers of 8 way dip switches SW1 and SW2 are provided for pick up (high level) and
drop off (low level) voltage for catenary indication. The respective
setting range will be as follows :
Drop off : 48% to 70% (12 kV to 17.5 kV = 48V to 70V)
Pickup : 60% to 80% (15 kV to 20 kV = 60V to 80V)
The Dip switch settings will be in steps of 1 kV.
TYPE -IV
Page No : 45
-
8/8/2019 Scada Hardware Manual
46/99
meritHARDWARE MANUAL
COMPONENT LAYOUT
Page No : 46
-
8/8/2019 Scada Hardware Manual
47/99
meritHARDWARE MANUAL
The DC signal corresponding to AC ON input voltage would be stepped down using
suitable resistor path selected by DIP switch. This will be fed to input of the pick up
comparator and the trimpot is to be adjusted to make output high. Then the AC OFF
input voltage is to be set using suitable resistor path selected by DIP switch. This will be
fed to the input of Drop Off comparator and the respective trimpot is to be adjusted to
make output high.
Then the AC OFF input voltage is to be set using suitable resistor path selected by DIP
switch. This will be fed to the input of Drop Off comparator and the respective trim pot is
to be adjusted to make the output high.
Both of these comparator outputs ( U1-U3 ) are to be connected to input of the AND gate.
This energizes the output relay through driver transistor. The field signal input is
connected through 32 pin Half Euro connector. The output from this card goes to Digital
Input Function Module of Logic Chassis through Euro connector.
5.5.3.0 Modem
The word MODEM is an acronym for MOdulator and DEModulator. Modem is used to
transfer data between two computers located at a distant place by using a normal
telephone line.
Page No : 47
-
8/8/2019 Scada Hardware Manual
48/99
meritHARDWARE MANUAL
5.5.3.1 Overview of SCADA Modem
The basic configuration consists of one master modem and one or slave modems
connected. The transmit output of master modem is connected to transmit output of all
slave modems. The receive input of master modem is connected to transmit output of all
slave modems. Multi-drop Modem configuration can be either 2 wire or 4 wire
configuration. Our Railway SCADA Multi-drop modem configuration is 4-wire
configuration The mode of communication between master and slave modem is always
half duplex mode. At any given time either master modem will be transmitting data to
slave modem will be transmitting data to the master modem.
5.5.4.0 POWER SUPPLY UNIT
5.5.4.1 Principle of Operation
The RTU Power supply consists of two parts , one for main 24 v dc Supply and the other
is (5v, 12v,-12v) for Modem and interface card reference supply.
Supervisory Module
The function of this card is to monitor the presence of the input AC voltage and change
over to battery whenever the input AC voltage crosses beyond the specified limits which
is less than 155 V or greater than 290 V.
The Supervisory module monitors the input voltage to check the High/Low value.
The relay circuitry is used to control the AC/DC Supply switch over.
The DC LOW, and AC Fail Status also be provided by this module to Digital
Input Module
5.5.4.2 PROTECTION FEATURES
5.5.4.2.1 Mains supervision : When AC Mains voltage is between 155V AC to 290V AC as
specified in the RDSO document then AC Mains will be connected to the DC-DC
Page No : 48
-
8/8/2019 Scada Hardware Manual
49/99
meritHARDWARE MANUAL
converter, otherwise 110V DC battery voltage will be connected.
5.5.4.2.2 Battery supervision : When battery voltage is between 99V DC to 140V DC as
specified in the RDSO document then Battery voltage will be connected to the DC-DC
converter. Protection of electronics from surges and noises are taken care by using
transient voltage suppressors and line filters. Transient voltage suppressor will prevent
the abnormal rise of AC input voltage. Line filters will provide filtering of electrical noises
of DC supply given to the SMPS.
Page No : 49
-
8/8/2019 Scada Hardware Manual
50/99
meritHARDWARE MANUAL
Block diagram of Power supply
PWER SUPPLY WIRING DIAGRAM
Page No : 50
-
8/8/2019 Scada Hardware Manual
51/99
meritHARDWARE MANUAL
Block diagram of psu of LDA75f
Page No : 51
-
8/8/2019 Scada Hardware Manual
52/99
meritHARDWARE MANUAL
component layout of LDA
Page No : 52
-
8/8/2019 Scada Hardware Manual
53/99
meritHARDWARE MANUAL
Ckt of psu LDC 30F
Page No : 53
-
8/8/2019 Scada Hardware Manual
54/99
meritHARDWARE MANUAL
component layout of lLDC 30f
This power supply unit is to work with 240V AC from MAINS. If this voltage goes below
155V AC, then the input will be cut off and it has to reach 175V AC to become normal. If
the AC input goes above 290V AC, then it will be cut off. Whenever AC is cut off due to
high or low level, then the 110V DC input voltage from Battery is to be connected. If this
Page No : 54
-
8/8/2019 Scada Hardware Manual
55/99
meritHARDWARE MANUAL
voltage goes below 80V DC, then it has to reach 95V DC to become normal. If it goes to
140V DC and above it will be cut off.
5.5.4.3 Functional Description of LDA75FThe DC input voltage is provided through Molex connector at the line and neutral points.
A 3Amps fuse isolates the power, which is filtered by spike noise suppression capacitor
C11. A damper discharge resistance bleeder for this capacitor is formed by resistor
network. The leakage and mutually inductive coupled input is fed to the rectifier bridge.
The Negative output is AC Grounded to flame grounded before feeding through inrush
limiting thermistor to tank capacitors. A LC filter combination will filter the rectified output
to feed a steady current into primary of transformer.
The primary winding of transformer are current switched by MOSFET TR31 at 140 KHz
to generate an average input current of 3.3 Amps at 200v AC. Auxiliary winding pin
provide for soft start control with capacitor. The PWM (Pulse Width Modulation) control
has pulse modulated between primary winding of the transformer. The output terminals
of the transformer operate a common cathode dual diode in the feed forward mode
through inductances. The output is RC damped and LC filtered. Any over/under shoots
are damped by bleeder resistor network. The output voltage is crowbar clamped with
zener diode and optically coupled.
The voltage control is affected by programmable IC, which has comparator resistors
network for output setting. The Positive/Negative terminals of output are floating with
respect to ground. The Output Voltage of LDA75F is +24 V DC (3.2 Amps).
5.5.4.4 Functional Description of LDC30F
The DC input voltage is provided through Molex connector at the line and neutral points.
A 3Amps fuse isolates the power, which is filtered by spike noise suppression capacitorC11. A damper discharge resistance bleeder for this capacitor is formed by resistor
network. The leakage and mutually inductive coupled input is fed to the rectifier bridge.
The Negative output is AC Grounded to flame grounded before feeding through inrush
limiting thermistor to tank capacitors. A LC filter combination will filter the rectified output
to feed a steady current into primary of transformer.
Page No : 55
-
8/8/2019 Scada Hardware Manual
56/99
meritHARDWARE MANUAL
The primary winding of transformer are current switched by MOSFET TR31 at 140 KHz
to generate an average input current of 1.3 Amps at 200v AC. Auxiliary winding pin
provide for soft start control with capacitor. The PWM (Pulse Width Modulation) controlhas pulse modulated between primary winding of the transformer. The output terminals
of the transformer operate a common cathode dual diode in the feed forward mode
through inductances. The output is RC damped and LC filtered. Any over/under shoots
are damped by bleeder resistor network. The output voltage is crowbar clamped with
zener diode and optically coupled.
The voltage control is affected by programmable IC, which has comparator resistors
network for output setting. The Positive/Negative terminals of output are floating withrespect to ground. The output Voltage of LDC30F is +5V (3.0 Amps), +12V(1.2Amps)
and 12V(0.3 Amps).
5.5.4.5 Over current Protection
Over current protection circuit is built-in to be operated over 120% of the rated current.
This function works to protect against short circuit and over current condition, which is less
than 20 seconds, when cause of activation of over current protection is removed, theoutput will be automatically recovered.
Page No : 56
-
8/8/2019 Scada Hardware Manual
57/99
meritHARDWARE MANUAL
Supervisory 1 OF 2
Supervisory 2 OF 2
Page No : 57
-
8/8/2019 Scada Hardware Manual
58/99
meritHARDWARE MANUAL
PCB LAYOUT OF SUPERVISORY
5.5.4.6 Over Voltage Protection
Over Voltage Protection is builtin and will be operated at 290 of the rated input Voltage.
When this function operates, input should be shut off. Output Voltage will be recovered
Page No : 58
-
8/8/2019 Scada Hardware Manual
59/99
meritHARDWARE MANUAL
whenever the input supply becomes Normal.
5.5.4.7 Fold Back Characteristics
INPUT Pick up Drop off
A.C Input Voltage
(High Range)
270V AC 290V AC
A.C Input Voltage
(Lower range)
155V AC 135V AC
Hysterisis: 20 V AC for both Higher and Lower range.The output voltages are as follows:
1. Logic Chassis
+24 v DC with respect to GND
2. Modem
+12V DC
-12V DC
+5V DC with respect to GND
3. Contactors
24V DC with respect to GND
4. Interface Cards
+12V DC with respect to GND
5.5.6.0 Contactors / Relays
The Contactors are used to activate the field devices such as Circuit breakers, Interruptors,
Transformer TAP positions and Autoreclosure lockouts. The rating of these contactors is
as follows
Make - C & S
Page No : 59
-
8/8/2019 Scada Hardware Manual
60/99
meritHARDWARE MANUAL
Coil voltage - 24V DC
Contactor rating - 10A
No. Of contacts for CB / BM - 3 NO + I NC
No. Of contacts for Auto reclosure - 2 NO + 2 NC
These contactors are suitable for DIN rail mounting as well as screw mounting. DIN rail
mounting offers ease of assembly in the panels.
These are made of flame retardant thermoplastic material. These are very strong, compact
and light in weight. Mounting space is saved due to its compact design.
Enclosed contacts and shrouded terminals ensure protection against accidental touch. Due
to modular design, replacement of coil is very easy without disturbing the power
connections. Accessibility for change of coil is from the front. The terminals have self
propelling washers for easy connections, bounce free contact system and high contact
pressure makes the contactor suitable for high making and breaking currents.
The Relays are used in the Interlocking circuit and under voltage circuit.
Make : OEN / 4R Series
Type : 4R Series
No. of contacts : 3 Changeover
Coil voltage : 24V DC
Contact rating : 2A
Page No : 60
-
8/8/2019 Scada Hardware Manual
61/99
meritHARDWARE MANUAL
Schematic for tele command
Page No : 61
-
8/8/2019 Scada Hardware Manual
62/99
meritHARDWARE MANUAL
Schematic for hv cb tele command
TAP POSITION
Page No : 62
-
8/8/2019 Scada Hardware Manual
63/99
meritHARDWARE MANUAL
5.5.7.0 Terminal Block
Terminal Block is used to interconnect the field cables and RTU internal cables to
perform the control and supervisory operation at the field. Interconnection between RTU
and field terminal block is done in the switching stations to collect the Status / Alarms and
control the Field equipment. The RTU terminal block section is designed in such a way
that separate terminal sections are arranged for Tele commands, Tele signals and
Telemetry.
Note : Please Refer Annexure I & II for Terminal Block Connection Details.
5.6.0 DESCRIPTION OF TELEMETRY SYSTEM AT TSS
5.6.1 Under-voltage Tripping of Bridging Interrupters
Page No : 63
-
8/8/2019 Scada Hardware Manual
64/99
meritHARDWARE MANUAL
This scheme is applicable only under extended feed condition. The arrangement is such
that the bridging interrupters at SP can be closed only when OHE is dead on one side of
neutral section. The under voltage scheme becomes operative only after the bridging
interrupter is closed. When the undervoltage scheme is in active condition and if OHEvoltage goes below the set level, then the bridging interrupter will be tripped by the under
voltage circuit. The logic program is designed such that if both the catenaries are low as
per the set value then the respective Bridging BM open command will be executed at
RTU level.
5.6.2 Scheme of Telemetry at SP
The arrangement is such that a Power Meter is used to measure the voltage of either up
line or down line. In case of failure of any one line, the Power Meter will be connected to
the other line through the PT changeover circuitry. The changeover will be effective
based on the settings on catenary indication circuit.
5.6.3 Scheme of Catenary Indication at SP
The arrangement is such that the catenary indication is available at the pick up voltage and
will go off at the drop off voltage selected and set by the user.
The pick up voltage selection range is available from 60% to 80% of PT voltage and drop off
voltage is available from 50% to 70% of PT voltage. The pick up and drop off settings
have been provided to take effect of induced voltage in adjacent OHE which otherwise
may give false indication of OHE live, even after section has actually been de-energised.
The arrangement of these settings programmed in the CPU card.
Page No : 64
-
8/8/2019 Scada Hardware Manual
65/99
meritHARDWARE MANUAL
SCHEME OF TELEMETRY AT TSS
5.6.4 Closing of Bridging Interrupter
When OHE is dead on one side of SP, then the bridging interrupter can be closed. This is
Page No : 65
-
8/8/2019 Scada Hardware Manual
66/99
meritHARDWARE MANUAL
achieved for BM1 as given below. One end to close command contactor (NT) coil is
permanently connected with +24V and the other end is controlled by a command driven
by a Digital output module. The respective output of the Digital output module is
programmed to give command when any one of the catenary values becomes low whichis sensed from the respective Transducer connected to the Analog input module.
5.6.5 Under voltage Tripping of Interrupter
When under voltage circuit is in active condition, if OHE voltage becomes low below the set
level due to any fault, then the bridging interrupter is to be tripped.
To achieve this function, one end of the trip command contactor (FT) coil is connected +24V
DC, and the other end is connected to the Digital output module. Whenever both theadjacent catenaries are going low then the respective Digital output channel will enable
the FT coil to trip the Bridging BM.
Note : The Software is designed such a way that the bridging interruptors can be
closed only when the section on one side of neutral section is dead and the under
voltage circuit become operative only after the bridging interrupter is closed.
5.6.6 Sequence of operations of under voltage Tripping
1. When OHE voltage is available on both sides of SP, then the close command should
not be executed.
2. When OHE is dead in any one side of the SP (i.e. PT1 or PT2), the operator will be able
to close the bridging interrupter by energizing NT coil.
3. When both the PT fails under the feed extended condition, then the respective Digital
output module will initiate the command to trip the Bridging BM without Operators action.
Page No : 66
-
8/8/2019 Scada Hardware Manual
67/99
meritHARDWARE MANUAL
Hardware Schematic
Page No : 67
-
8/8/2019 Scada Hardware Manual
68/99
meritHARDWARE MANUAL
Hardware schematic
5.6.7 Catenary Voltage Sensing at TSS
The secondary of 25 KV / 100V PT is fed to the catenary indicator, under voltage
tripping and telemetry circuit. This voltage is stepped down by the Transformer,
rectified through a bridge rectifier and filtered of transients with capacitance
filter C. An MOV (Metal Oxide varistor) is provided across the input to act as
surge arrestor.
For catenary indication, 2 nos of 8 way dip switches SW1 and SW2 are provided for
Page No : 68
-
8/8/2019 Scada Hardware Manual
69/99
meritHARDWARE MANUAL
selecting pick-up (high level) and drop off (low level) voltage. The respective setting
range will be as follows :
Drop off : 48% to 70% (12 KV to 17.5 KV = 48V to 70V)
Pick up : 60% to 80% (15 KV to 20 KV = 60V to 80V)
The Dip switch settings will be in steps of 1 KV.
WARNING
IT IS TO BE ENSURED THAT THE DROP OFF VOLTAGE SETTING IS ALWAYS
LESSER THAN PICK-UP VOLTAGE SETTING FOR PROPER OPERATION OF
SCHEME
5.6.8 Scheme of Telemetry at TSS
The arrangement is such that a POWER METER is used to measure the voltage of either
up line or down line. In case of failure of any one line, the Transducer will be connected
to the other line through the PT changeover circuitry. The changeover will be effective
based on the settings on catenary indication circuit.
5.6.9 Auto Re-Closing scheme at TSS
In case of tripping of the feeder circuit breaker on fault at TSS, a single shot auto-reclosing
scheme re-closes that breaker automatically only once after a pre-set time delay. In the
event of any fault on OHE presisting the feeder circiut breaker trips again and and
autoreclosing scheme gets automatically locked out to prevent reclosing of the breaker a
second time. The locked out condition is telesignalled to RCC. The operator releases the
locked-out condition when a telecommand is initiated through the keyboard console.
5.6.10 Field Wiring
Page No : 69
-
8/8/2019 Scada Hardware Manual
70/99
meritHARDWARE MANUAL
Interconnection between RTU and field terminal block is done in the switching stations to
collect the Status / Alarms and control the Field equipment. The RTU terminal block
section is designed in such a way that separates terminal sections are arranged for Tele
commands, Tele signals and Telemetry.
Field termination cables are used with different thickness to meet the current carrying
capacity of the field equipment. Different color cables are used for easy identification of
the signals in the field. Cable terminations are numbered using the ferrules for the
traceability of the signals. Signal cables, Power cables and Communication cables are
routed in different PVC pipes from RTU to field terminal block.
Auto reclosing
CHAPTER 6
Page No : 70
-
8/8/2019 Scada Hardware Manual
71/99
meritHARDWARE MANUAL
6.0 MAINTENANCE OF SCADA SYSTEM
6.1 Maintenance philosophy
In the event of failure of the system, it is recommended to identify the faulty printed circuit
card and replace the card with a working card. The recommendation is based on the
complexity of trouble shooting and technology used for mounting of component as
explained below:
1. The system is based on the microcontroller technology where almost every
component has a very high level of integration. The components perform multiple
functions, as the level of integration is high.
Therefore, the component has to be tested for all its intended functions to
conclude whether it is faulty. The testing engineer should know each and every
function of the component under test and the testing methods. Hence, component
level troubleshooting needs a specialist with special tools.
2. The components are soldered to the Printed circuit card with surface
mounting technology. Removal of faulty components from the card and soldering of
a new component on to it also needs a skilled person with special and expensive
tools. These tools are generally used only in a production centre.
Maintenance of SCADA system may be classified into two as preventive and corrective
maintenance. Preventive maintenance is to reduce the number of failures and corrective
maintenance to put back the failed system into operation.
6.2 RTU Power Supply Unit
1. Switch off the RTU and check the Power Supply Gently for any loose contact if so tight the same.
2. Switch On Both AC & DC Supply. Check AC to DC Changeover during the violation of set limit for
input voltage. Also Check DC to AC Changeover and observe the AC Fail & DC low indication onRTU.
3. During Changeover observe any disturbance in CPU Module.
4. To Measure the Ripple Voltage in D.C
Page No : 71
-
8/8/2019 Scada Hardware Manual
72/99
meritHARDWARE MANUAL
5. Measure the Output Voltage of RTU power Supply of MCB and ensure that the deviation is with in
the limit as indicated in the below. If any voltage falls beyond its limit then replace the related
Module.
Input Limit
240V AC ( 155 to 290 V)
110 V DC ( 100 to 130 V)
+24V DC (+/- 2 VDC)
+5 V DC (+ 1 V / - 0.1VDC)
+12 V DC (+/- 1 VDC)
-12 V DC (+/ - 1 VDC)
6.3 UPS SYSTEM
The UPS System is conservatively designed. It is completely static with all advanced
digital circuits. This system will provide many years of trouble-free service with minimum
maintenance. However a regular periodic maintenance program should be followed.
Table given below provides the schedule maintenance procedure in detail.
WARNING
HIGH VOLTAGE IS USED IN THE OPERATION OF THE SYSTEM. HENCE EXTREME CARE
SHOULD BE TAKEN WHEN PERFORMING MAINTENANCE TASK OF TROUBLE SHOOTING
THIS SYSTEM, TO PREVENT ACCIDENTAL ELECTRIC SHOCK
Page No : 72
-
8/8/2019 Scada Hardware Manual
73/99
meritHARDWARE MANUAL
TABLE - 1
6.4 TABLE OF PERIODIC INSPECTION AND MAINTENANCE
Sl No ITEMS INSPECTION PERIOD PROCEDURE
1 Ventilation
& opening
Daily Daily Check that intake and exhaust air
openings are not obstructed.
2 Chassis
Assemblies
Weekly Weekly Remove dust & foreign particles within
& Battery the chassis & battery bank
using compressed air or blower. Check
mounting bolts and terminals for
looseness, tighten them, keep the
battery terminals clean.
3 Cabinet 3 Months 3 Months Inspect the transformers, chokes for
evidence of heating, damaged
insulation, loose mounting of screws.
Correct any malfunctioning before
operating the unit. Tighten any loose
screws or nuts, clean electrical
contacts with a cloth dampened with
carbon tetrachloride. Do not use
cleaning solvent on electrical contacts.
Replace if found defective.
4 Controls 3 Months 3 Months Controls 3 Months Check all indicator
lamps
5 Controls 6 Months 6 Months Check all the controls for operability.
Check the operation of meters.
Replace if any damage or mal-
functioning is observed.
6 Controls 12 Months 12 Months Check the cable for input and output
power and internal wiring to
components. Check for cracks or
broken insulation. Replace as
indicated.
7 12 Months 12 Months Inspect the general conditions of
PCBs. Check the components for
Page No : 73
-
8/8/2019 Scada Hardware Manual
74/99
meritHARDWARE MANUAL
evidence of over heating, cracks
orpeeling. Repair or replace board, if
necessary.
8 12 Months 12 Months Inspect diodes and silicon Controlled
rectifiers and their heat dissipators for
loose mounting or defective electrical
connections. Tighten screws and nuts.
9 12 Months 12 Months Inspect PCB, sockets for loose
components electrical connections.
Tighten the mounting screws & replace
defective sockets, if any.
10 12 Months 12 Months Inspect terminal boards for breakage or
dry joints. Replace if necessary thedefective TB. Tighten mounting screws
if necessary.
11 Inspect the electric wiring for broken
solder connections or peeled insulation
and general deterioration. Repair or
replace wiring. Use carbon
tetrachloride in well ventilated areas.
Do not breathe fumes.
6.5 FAULT FINDING AND RECTIFICATION
When replacing the components, observe the following :
Page No : 74
CAUTION
FUSE REPLACEMENT MUST BE MADE ONLY WITH TYPES SPECIFIED IN THE
PARTS LIST
-
8/8/2019 Scada Hardware Manual
75/99
meritHARDWARE MANUAL
1. When soldering avoid excessive heat which may damage associated
components.
2. Be careful while making all soldering joints, as a poorly soldered joint can
cause further trouble and is one of the most difficult faults to locate.3. Do not drop drips of solder or hardware into the chassis.
4. Do not damage leads of other components by pushing or them aside.
5. Maintain a log of all repairs and adjustments. Comprehensive notes and an
accurate log, make it possible to reverse the procedure or to facilitate the
communications regarding repair procedure.
6. When detaching wires from components, mark the wire with tape to ensure
correct re-wiring.
7. Always place the component in the exact position occupied original.8. Whenever one or more components have been replaced, testing and
readjustment of appropriate circuit is necessary.
6.6 TESTING EQUIPMENT REQUIREMENT
Whenever it becomes necessary to replace any of the components in the UPS, re-
adjustment of the appropriate circuits may be necessary. Familiarity with the Systems
and judgement must be exercised when determining, which component effect re-
adjustment. Following Table lists the test equipment required for reforming adjustment
servicing :
6.7 TEST EQUIPMENT
EQUIPMENT WITH MODEL / TYPE QTY Mfr
Oscilloscope with Dual Channel 1 no. APLAB
Page No : 75
-
8/8/2019 Scada Hardware Manual
76/99
meritHARDWARE MANUAL
Voltage Probes into 10 Model 2 nos APLAB
Digital Multimeter Type 1 no. NIL
Distortion Meter 1 no. APLAB
Decade Resistance 1 no. APLAB
Card Servicing Unit 1 no. Numeric
CHAPTER 7
7.0 RTU TROUBLE SHOOTING PROCEDURE
7.1 TELESIGNAL
The problems in the field equipment can be classified into three types
a). Telecommand (BM/CB) not operating
Page No : 76
-
8/8/2019 Scada Hardware Manual
77/99
meritHARDWARE MANUAL
b). Telesignal (BM/CB status and Alarms) not coming
c). Telemetry (Voltage/Current) not received from the post
1. Check the 110 V DC at respective RTU terminal block as per the Field
Termination Chart or the Wiring Diagram where this voltage comes from the field
devices. If there is no voltage at RTU terminal block then the problem is not with
RTU. Check the field equipment side and the cable continuity. If the voltage is
available then follow the next step.
2. Replace the respective DIM d as per the wiring diagram or Field termination
Chart and check respective LED indication at DIM card.
.
7.2 TELEMETRY
1. Check the respective PT/CT secondary at RTU terminal block as per the wiring diagram
or the Field Termination Chart.
2. If there is no required minimum Voltage or Current then the problem is not in the RTU
side. Check the field devices and the interconnecting cables.
Page No : 77
-
8/8/2019 Scada Hardware Manual
78/99
meritHARDWARE MANUAL
3. Check the POWER METER input Voltage or Current. If there is no Voltage or Current
then check the cable between the RTU terminal block and Power Meter input.
4. Check the power Meyer output, if there is no serial output with respect to input voltage
or current then replace the Power meter check the value at RCC.
5. Replace the flat cable and check the value at RCC.
7.3 TELE COMMAND
Page No : 78
-
8/8/2019 Scada Hardware Manual
79/99
meritHARDWARE MANUAL
1. Check the Selected channel enable and indication is proper. If channel does not
glow, the problem may be resolved by changing the following items one after
another.
Change the DOM card.
a. If the problem is not resolved, then change the cable termination.
b. If the channel glows, then check the contactor operates. Otherwise check for 24
V DC across coil; if voltage is available, then replace the contactor.
c. If the coil voltage is not available, then check the 24 V DC Supply at terminal
block TB1.
d. If the contactor operates, then check the NO contact for input and output
voltages; if available, then problem is in the Field devices side.
e. If the 110 V DC is not available on the input side then the problem is again on
the railway terminal board. If voltage is available on the input side but not
available on the output side then change the contactor.
7.4 Power Supply Unit :
( If output voltages are not coming)
Page No : 79
-
8/8/2019 Scada Hardware Manual
80/99
meritHARDWARE MANUAL
1. Check the input voltage of the LDA (OR) LDC Module at Molex connector CN1. (if the
Voltage is available go to step-7
2. If the Input Voltage is not present ,Check the output voltage Supervisory Module
at Molex Connector JP4.
3. If the supervisory card input voltage is not present , then check the A/C input voltage at
connector JP1.
4. If the A/c Input voltage is not present then check the MCB-1 input & Output. ( The
Voltage Must be less than 290v and greater than 155v )
5. If the D/C Input voltage is not present then check the fuse (F3) and MCB-2 Input and
Output.( The Voltage must be less than 140v and greater than 90v DC)
6. If the Fuse (F3) blown up, then replace the 2A fuse (20mm)
7. If the the LDA /LDC input voltage is present at connector CN1 ,
Then check the module fuse (F1).
8. Check the Output voltage at connector (JP3) for +5v/+12v/-12v.
( Check the Molex pin connection and crimping )
9. Check the Output voltage at Connector (JP5) for 24v/DC.
( Check the Molex pin connection and crimping )
7.5 TROUBLESHOOTING CHART FOR UPS
NO FAULT SYSTEM REASON REMARKS1 System working on mains but
not working on batteryBattery fuse blown Check the battery polarity and
replace the fuse.
Page No : 80
-
8/8/2019 Scada Hardware Manual
81/99
meritHARDWARE MANUAL
2 Charger not coming ON whenswitched ON
Mains input fuse failed ormains MCB tripped
Check the rating of the fuse.If itis of lower rating, replace withproper fuse.
Input fuse of the chargerblown
Check the battery polarity and
connection. Correct if it iswrong. Replace the fuse
Contactor not coming ON Check the input supply. If
present, check the wiring of
Contactor & rectify it. Check the
coil. Replace if faulty.3 Mains Input Fuse Failure Very low input
voltageProvide rated input voltage.
Input cable capacityis less
Replace the wiring with correctly
rated cable.
Loose contact in theinput wiring
Tighten the connections.
4 DC Under Voltage indica tioncomes on even when DCvoltage is nominal and theInverter Trips.
Inverter Fuse blown Replace the fuse
5 DC under Voltage comesimmediately after the Inverter isswitched on (NO LOAD) andInverter Trips
Mains input cable is lessthan rated capacity
Replace the cable from D.B.
with correctly rated capacity.
6 DC under voltage indicationcomes on while working onBattery (in the absence ofmains) and Inverter trips.
Battery is dischargedBattery cable of lessercapacity less than ratedLoad surge.
Keep the battery in charged
condition Replace the cable with
a correctly rated cable.7 Overload Indication comes on
while the load is switched ONVoltage reaches 230V Switch on the loads one by
one .
7.6 Trouble Shooting Procedure for Modem :
Page No : 81
-
8/8/2019 Scada Hardware Manual
82/99
meritHARDWARE MANUAL
Team link SCADA modem is designed in such a way that it requires just plug in the modem
for normal operation. In case the polling operation does not take place the following points
will facilitate the first line maintenance of the card.
Check for correct ness of the jumper setting.
A) Ensure all the modems involved are powered on.
1. Make sure that the power card is kept correctly, 230v, AC in case of master modem,
DC voltage in case of Slave modem.
2. Verify that the modem is powered on by observing the MR led glowing on the front
panel.
B) Ensure that the modem to RTU /MTU connections are proper.
1. Verify that the RTU/ MTU signals are coming properly at the RS-232C cable coming
from RTU/ MTU. Verify the following signals are in the range of 3v to 15v at the RS-
232 C Cable coming from RTU/ MTU.
-Transmit Data (TXD) at Pin No. 2 of RS-232C cable coming from RTU/
MTU .
- Request to send (RTS) at Pin No. 4 of RS-232C cable coming from RTU/
MTU
- If the voltages are not present then check for the continuity of the cable.
- If the signals are present ensure that the RS-232 Cable is mating properly
with corresponding Connector of the modem end.
C) Ensure that the Modem to Modem connection are proper.
Page No : 82
-
8/8/2019 Scada Hardware Manual
83/99
meritHARDWARE MANUAL
1. Ensure that the connection from the Master modem are properly connected
to Slave modems.
2. Check the continuity of the Communication Line.
D). Ensure that the Modems are operating properly
Check for MR led on the modem, if MR is glowing put the Analog loop back switch in to
On position and send data and check, if data is not correct modem could be faulty. If
data is correct then connect the modem with any one of the Remote modems and ask
them to put in to Digital Loop back switch in to ON position, send data and receive,
check for correctness. If the data is not correct check for communication cable. If thedata is correct then,
Start the polling cycle and observe the following
1. Master Modem:
- CTS led should always be glowing.
- TD and RD led should blink
2) Slave Modem:- DCD led should glow, if not check for the communication cable.
- RD led should blink, if not check the following
- Check the RS-232 cable from RTU.
- Check whether RTU is responding for the polling.
If still the problem persists then replace the modem .
7.7 TELESIGNAL FAULT FINDING CHART
Page No : 83
-
8/8/2019 Scada Hardware Manual
84/99
meritHARDWARE MANUAL
Page No : 84
CHECK THE RTU TERMINAL BLOCK FOR110V FOR FIELD INPUT
110V AT
TB
NOT A RC PROBLEM
REPLACE DIM
DIM LED
IS
GLOWING
REPLACE DIM
MODULE
NO
YES
YES
YES
NO
NO
PROBLEM SOLVED
-
8/8/2019 Scada Hardware Manual
85/99
meritHARDWARE MANUAL
7.8 TELEMETRY FAULT FINDIING CHART
Page No : 85
CHECK THE RTU TERMINAL BLOCK FOR
FIELD INPUT
FIELD
INPUT NOT A RCPROBLEM
CHECK FUSE &CABLE FOUND
FAULTYREPLACE IT.
REPLACE THE
Power Meter
NO
YES
YES
YES
NO
NO
CHECKPOWER Meter
INPUT &
Supply
CHECK
POWER
METER
OUTPUT
PROBLEM SOLVED
-
8/8/2019 Scada Hardware Manual
86/99
meritHARDWARE MANUAL
7.9 TELECOMMAND FAULT FINDING CHART
8.0 DOWNLOADING PROGRAM TO RTU MICROCONTROLLER:
Procedure:
Page No : 86
CHECK THE RESPECTIVE CHANNEL LED IS
ENABLED
LED
ENABLE
D
REPLACE DOTMODULE
CHECK THEO/P
VOLTAGE
AT TB
PROBLEM SOLVED
NO
YES
YES
YES NOCONTACTOR IS
OPERATING
CHECKVOLTAGE
ACROSS COIL
REPLACE THE CABLE
YES
REPLACE THECONTACTOR
CHECK THE WIRING FOR LOSSE
CONNECTION. ANY DAMAGE REPLACE IT
NO
NO
-
8/8/2019 Scada Hardware Manual
87/99
meritHARDWARE MANUAL
1. Set the jumper J2 of CPU to download mode. Connect the serial-port-1 of CPU tosystem serial port.
2. Software used for Download Program: C:\SCSI\BIN\SPJTERM.EXE
The preloaded SPJTERM.EXE is the programming tool of the micro controller used in theRTU.
3. After opening the program click Settings to set the communication Settings.
4. Set the parameters as shown below.
5. After setting the port parameters click port open to initialize the serial port.
Page No : 87
-
8/8/2019 Scada Hardware Manual
88/99
meritHARDWARE MANUAL
The window will appear as shown below.
6. Click the In System Programming in File menu.
RTU is now ready for download and the communication is now initialized with theController.
7. Set all the parameters as shown below.
Page No : 88
-
8/8/2019 Scada Hardware Manual
89/99
meritHARDWARE MANUAL
8.Click Full Chip Erase to clear the buffers of Micro controller.
9. Click Browse and select the .HEX file of RTU download file. The path and name of the filewill be appearing on the band HEX file to download.
10. Click Program to start the downloading.
Page No : 89
-
8/8/2019 Scada Hardware Manual
90/99
meritHARDWARE MANUAL
The above shown window will disappear after download is completed. Switch off the RTUand set the jumper J2 of CPU to normal position and Switch ON. RTU is now ready fornormal working.
9.0 Download Parameters to RTU
Procedure :
1. Software used for Download Program: C:\ADRA\MERITDIAG.EXE
The preloaded MERITDIAG.EXE is the downloading tool of the Merit RTU.
2. Click Baud Rate and set the speed of serial communication. Default-600.
Page No : 90
-
8/8/2019 Scada Hardware Manual
91/99
meritHARDWARE MANUAL
3. Click Comm Port and set the serial port to witch the RTU is connected. Default-Comm 1.
Page No : 91
-
8/8/2019 Scada Hardware Manual
92/99
meritHARDWARE MANUAL
4.Click Setup and set the parameters to download to the RTU.
5. After setting the parameters click Download & Update button to set the RTU parameters.
Note: Before Clicking Download & Update make sure that the Digital Input Modules and the
Digital Output Modules selected must match the actual modules inserted in the RTU. While
setting the slot for Digital Output modules the RTU will start from the number of digital input
modules and the slots will be allocated automatically after the Digital Input modules. If amismatch occurs while download, the modules will gets damaged and may cause serious
damages to the whole unit.
Setting of Analog Input Channels:
SSP - 0
SP - 2
Page No : 92
-
8/8/2019 Scada Hardware Manual
93/99
meritHARDWARE MANUAL
TSS/FP - 8
Now the RTU is ready for communication and operation. All the DI, DO and AI channels can
be checked through MERITDIAG.
6. The RTU running memory buffers can be cleared by clicking Reset RTU Database.
7. The RTU real time clock can be set by clicking Set RTU Time.
9.1 Testing the various parameters using MERITDIAG:
1. Click Scan Digital Inputs. The window will appear as shown below. All the DI channels
can be tested and viewed.
Page No : 93
-
8/8/2019 Scada Hardware Manual
94/99
meritHARDWARE MANUAL
2. Click Scan Output Status. The window will appear as shown below. All the DO
channels can be tested and viewed
Testing Procedure: Click on the channel to be tested.
Press space bar once. On will appear.
Page No : 94
-
8/8/2019 Scada Hardware Manual
95/99
meritHARDWARE MANUAL
Click on Set Outputs. The particular channel will be made On by RTU.
Press space bar again. On will get disappeared.
Click on Set Outputs. The particular channel will be made off by RTU.
Press space bar twice. Timd will appear.
Click on Set Outputs. The particular channel will be made On and Off by RTU.
3. Click Scan Analog Inputs. The window will appear as shown below. Analog count ,
percentage and unit against all the AI channels can be viewed here.
Page No : 95
-
8/8/2019 Scada Hardware Manual
96/99
meritHARDWARE MANUAL
LIST OF ABBREVIATIONS
Page No : 96
-
8/8/2019 Scada Hardware Manual
97/99
meritHARDWARE MANUAL
A Amperes
AC Alternating Current
AIT Analog Input Termination
BM Bridging interrupter
CAN Controller Area Network
CB Circuit Breaker
CD Carrier Detect
CP Communication Processor
CPU Central Processor Unit
CT Current Transformer
CTA Cable Termination Module
DDC Bus Coupler Module
DC Direct Current
DIFM Digital Input Functional Module
DIT Digital Input Termination
DIP Dual-In-line Package
DMA Direct Memory Access
DOT Digital Output Termination
DRAM Dynamic Random Access Memory
EMF Electro Motive Force
EPROM Electrically Programmable Read Only Memory
FP Feeding Post
FSK Frequency Shift Keying
Hz Hertz
IBM PC International Business Machines Personal Computer
IC Integrated CircuitIDE Integrated Drive Electronics
IRQ Interrupt Request
LAN Local Area Network
LC Logic Chassis
Page No : 97
-
8/8/2019 Scada Hardware Manual
98/99
meritHARDWARE MANUAL
LED Light Emitting Diode
MB Mega Byte
MOBI Mod Bus Interface
MODEM Modulator Demodulator
MOSFET Metal Oxide Semiconductor Field Effect Transistor
MOV Metal Oxide Varistor
NC Normally Closed
NO Normally Open
NVRAM Non-volatile Read Only Memory
OHE Overhead Equipment
PC Personal Computer
PCB Printed Circuit Board
PCS Peripheral Chip Select
POST Power ON Self Test
PWM Pulse Width Modulation
RCC Remote Control Centre
RD Receive Data
RF Radio Frequency
RLA Relay
ROM Read Only Memory
RTS Request to Send
RTU Remote Terminal Unit
SCADA Supervisory Control and Data Acquisition
SCR Silicon Controlled Rectifier
SEB State Electricity Board
SH ShuntSIMM Single-in-line Memory Module
SP Sectioning and Paralleling Post
SSP Sub-sectioning and Paralleling Post
SVGA Super Video Graphic Accelerator
SW Switch
Page No : 98
-
8/8/2019 Scada Hardware Manual
99/99
meritHARDWARE MANUAL
TB Terminal Block
TCO Timer Counter Output
TD Transmit Data
TPC Traction Power ControlTSS Traction Sub-station
UPS Uninterrupted Power Supply
V Volts
VGA Video Graphic Accelerator
WAN Wide Area Network