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Single Section Digital Axle Counter

G36

G.G.Tronics - SSDAC

It is an Versatile Axle counting system configurable as

2DP1S, 3DP1S, 3DP2S (IBS), ASTo SPEC No. RDSO/SPN/177/2005 Ver 2.0 with Amendment 1G.G.Tronics SSDACThis is a fail-safe microcontroller based system with 2 out of 2 architecture suited for proving Block Section and Entry/Exit of station.

Salient features of SSDAC-G36, 2DP-1S:The system consists of a Start Fed Unit (SF), an End Fed Unit (EF) housed in location boxes adjacent to the track with associated axle detectors web mounted on the track. The distance between the unit & the detectors being 15m max.

The block section to be monitored can be up to 25Kms.

This is a rugged system & dispatched as a full package of assembled & tested equipment, to make installation & maintenance easier & quicker.

The SF & EF units communicate with each other in FSK mode at 1200bauds over a single pair of quad cable..

G.G.Tronics SSDAC

Salient features of SSDAC-G36, 2DP-1S:A diagnostic routine will be running continuously in both the units & will be exchanging information through communication over quad cable.

The axle detectors are fed with 21 KHz & 25 KHz in both SF & EF units.

VR & PR relays are provided in the relay box along with the system in the location box.

The system is based on phase reversal technology wherein the Tx & Rx signals will be in phase under no train condition & will be out of phase during detection of a wheel/axle.

G.G.Tronics SSDAC

Salient features of SSDAC-G36, 2DP-1S:The system is designed to work with 90-R, 52Kg, 60Kg rails.

The system is suitable for axle detection for train speed from 0 to 250KMPH with recognition of direction of movement of train..

The system can tolerate a vertical limit of worn out rail specified by RDSO as indicated below

Sl. No.Rail SectionVertical wear in mm160 Kg / meter13.00252 Kg / meter8.00390 R5.00

G.G.Tronics SSDAC

Salient features of SSDAC-G36, 2DP-1S:Very much suitable for last vehicle detection.Can work in RE/Non RE areas satisfactorilyThe system senses wheels above 550mm dia, by which only train wheels are detected & trolley wheels are ignored.

Motor trolley wheels are not counted & also will not lead to error condition.

Two consecutive motor trolleys entering the same section within a time gap of more than 6 seconds are allowed & will not cause the system to go to error.One motor trolley following a train is allowed.G.G.Tronics SSDAC

Salient features of SSDAC-G36, 2DP-1S:LED s are provided on individual modules for indication of different stages of the working of the system.G.G.Tronics SSDACSeven segment displays are provided on CPU module for bold display of status & error codes.LCD display modules of the unit & reset box provide plain English messages of status & error codes making the system highly user friendly during installation, commissioning & maintenance.

For resetting the system under different conditions, interactive & intelligent reset box is provided in the station.

Salient features of SSDAC-G36, 2DP-1S:The system accepts co-operative reset with piloting of a train or direct reset with/without line verification depending upon the field conditions.G.G.Tronics SSDACIf one field unit is reset & the second one is not reset within 5 minutes the reset initiation automatically gets cancelled.A 48V potential (from the 24V supply) is developed within the reset box for effecting the reset of the system.A voltage window circuit ensures that the reset potential is maintained within the limits of 36 to 52V.Foolproof working is ensured in hardware with polarization for avoiding mix up of positioning of modules in SF/EF units.

Salient features of SSDAC-G36, 2DP-1S:Co-existence of multiple units without interference is achieved by having 255 unique addresses through software.G.G.Tronics SSDACAmply protected with fuses & surge arrestors.Water clogging/flooding of track does not affect the working of the system.Anti theft fixing bolts are provided for the coils on the track.Deflectors are also provided for avoiding damage to the detector coils.The system works OFF 24V DC with a range of 20%, the average current drain being 10VUnder wheel condition Tx and Rx will be IN-PHASE 20V DC

Relay Driver card receives instructions from CPU for actuating Vital relay for blocking a section as soon as the first axle is detected. It is cleared after both IN and OUT counts of the section match.

COMMUNICATION CARDS (COM1 & COM2)G.G.Tronics SSDACCommunication between two SSDAC systems is through FSK communication at 1200bps V.23 standard along with CRC check Vital data like axle counts and system status are transmitted/received between the SSDAC system unitsThe digital data packet (consisting of count information, Direction information, Health of the equipment, Any error messages) generated by CPU is converted into analog form and sends to remote end evaluator through FSK communication.On other hand the information received in analog form from remote end evaluator is converted into digital and gives to CPUs.

COMMUNICATION CARDS (COM1 & COM2)G.G.Tronics SSDACTx Green indication should flash indicating that it is transmitting data.Rx Green indication should flash indicating that it is Receiving data.CD Green indication should flash indicating that carrier is available between the two evaluators.Clear to Send Indication. It should be flashing.Request to Send Indication. It should be flashing.No measuring points were given on Communication card.

DC-DC Converter cardG.G.Tronics SSDAC

Generates required multiple power outputs from 24VDC input

Monitoring Points DC-DC Converter

G.G.Tronics SSDACModuleMonitoring point Expected values DC-DC Converter+5VDC and GND4.75 to 5.25V DC+18VDC and GND17.75 to 18.25V DC+12VDC and GND11.75 to 12.25V DC-12VDC and GND11.75 to 12.25V DC+24VDC and GND22V to 26V DC

SM CPU and Event Logger CardG.G.Tronics SSDACSM-CPU or Event Logger CardMonitors the SSDAC system and logs vital events during normal and error operation with date and time stampAs many as 95 different events are recordedOptional display connected to Event Logger Card displays the communication errors happening in Real-time which aids in assessing the health of communication channelEvent logged during normal operation Communication status okVital and Preparatory Relay pickup / dropReset operations

Event logged during error operationCommunication link failSystem down due to failure of any cardVital and Preparatory Relay error status+5 VDC variationsErrors

Precautions to be taken for trouble free operationG.G.Tronics SSDACPower Supply-24DC: Use Axle Counter type , ripple free Charger Use 120 AH battery with adequate life Use 25 sq mm AL cable for feeding power to the systemProvide class B Surge Protector at source of 24 V DC in station Avoid tapping of different loads to the power source of Axle Counter

Precautions to be taken for trouble free operationG.G.Tronics SSDACQuad Cable:Loss should be less than 30 db between SF and EF(1.2 db/km)Every joint adds loss to the cable, minimize joints and take care for making good permanent joints .Insulation resistance to be more than 10 M ohms at 100 V DC between conductors ,between pairs and between wire and armor Loop resistance to be within 56 ohms/kmMaintain continuity of armor between SF and EF & earth at both ends .

Precautions to be taken for trouble free operationG.G.Tronics SSDACIt has come to notice that usage, termination and wiring of quad cable is far from satisfactory for trouble-free working of digital axle counters. Basic issue pertains to electromagnetic interference from parallel circuits in the cable and location. Following guidelines are recommended to enhance performance of DAC systems.Long parallel circuits shall be avoided in the same quad. Requirement is that parallel circuit shall be as far spaced as possible. So, one long and one short circuit can be accommodated in same quad but not both long circuits.DAC circuits in BPAC of up and down lines in double line sections shall be in separate quads and kept one/two quads away from each other as far as possible to avoid mutual interference due to long parallel circuits.DAC circuits in location shall not bunched along with parallel relay/power circuits. Relay circuits are known to generate switching transients that can couple enough energy in parallel circuits nearby and interference with low power circuits data circuits.Any other parallel wiring (relay circuits/power circuits/earthling wires etc) shall cross DAC circuits at perpendicular and any parallel portion shall be kept at minimum 150mm lateral distance away from the wiring for DAC circuits.Relay circuits shall preferably be not taken in the same cable as DAC circuits. In unavoidable circumstances relay circuits shall be in furthest quad (spatially) from the one containing DAC circuits.

Parallel Circuits:

Precautions to be taken for trouble free operationG.G.Tronics SSDACTwisting of Cable Pairs:Twisted pairs are required to avoid mutual interference between low level ac signals. Even short lengths of non-twisting (few inches) can couple enough differential mode electromagnetic signals to interfere with low voltage DAC communication signals.Quad cable twisting shall be ensured during termination so that minimum one twist per inch is maintained till the last inch into terminations.Any wiring from quad cable terminations to equipment shall be done by using twisted singles of indoor signaling cable (1mm square) or any other approved indoor twisted pair cable.Signaling cable or any other untwisted pair cable shall never be used in DAC communication circuits to avoid intermittent type of failure.

Precautions to be taken for trouble free operationG.G.Tronics SSDACContinuity and Earthing of cable armor & screen at intermediate terminations/Joints:Screening of quad cable of effective when induced current can flow in the screen thereby canceling/reducing the induction for the cable conductors. For adequate induced current to flow in screen, it is necessary that good earth connections are provided for screen & armor at all the cable terminations and joints.Quad cable screen & armor shall be made continuous at the intermediate terminations/joints by soldering and connecting both ends of cable screens & amours at the locations.Connections to screen shall preferably be made by metallic clamps soldered to screen to ensure good surface connection for electrical continuity. Combined earthing for both ends of armor and screen at intermediate locations shall be ensured to be in good condition and having values as low as possible but never more than 5.Earthing connection shall be kept short and as straight as possible because any loop or turns can create inductive elements that impede quick discharge of transients and surges to ground.

Precautions to be taken for trouble free operationG.G.Tronics SSDACEarthing :Earth resistance to be less than 2 ohms If not archived by single earth provide multiple earth and parallel then

Reset Box with LCD Display Clear condition of track

G.G.Tronics SSDAC

Reset PhilosophyTypes of ResetCo-operative Preparatory Reset with piloting for 2D and 3D-2S configurationsDirect Reset with line verification for 3D configuration

Reset Procedure2D : System powered onReset ModePrep ModePilotingClear Mode3D-2S: System powered onReset ModePrep ModePilotingClear Mode3D : System powered on Reset ModeLVClear ModeG.G.Tronics SSDAC

Reset PhilosophyG.G.Tronics SSDACFor Single line working one reset box is provided at the station associated with SF or EF unit of that trackIn double line section each station will have two reset boxes corresponding to the two units of the SF/EF for UP/Down lines.Normally co-operative reset with the running of the pilot train is accepted.When direct reset is required, line verification for the clear condition is necessary.Under special field conditions direct reset can be applied without line verification.The reset potential has to be within the range of 36 to 52V.

Reset PhilosophyG.G.Tronics SSDAC

The system accepts reset under the following conditions:

Initial power ON.When power fails & restores back when I/P voltage to the system fluctuates beyond limits.The reset is applied to both the field units.When there is an in count at the entry & at least one out count at the exit indicating the train has touched the end of block section.

Reset PhilosophyG.G.Tronics SSDACThe system will not accept reset under the following conditions:

When the section is clear.When the system is waiting for pilot train.When there is an in count but no out count is registered. (Occupied state)When reset is given only from one station (not co-operative)When the system is in permanent error status.When reset is applied at one end & the other end does not reset within 5 minutes.Removal of any of the PCB modules or fuses.Disconnection / damage of axle detector of coils

Reset PhilosophyG.G.Tronics SSDAC

Installation ProcedureThe installation can be taken up with the following parallel activitiesLaying foundation as per Railway standards for fixing the location boxTrenching for running the required length of cableDrilling of track for fixing TX/RX coils with the templateFixing of TX/RX coils on the trackLaying of power cables, signalling cables and cables from TX/RX coilsPainting and fixing of required planks and fuse the terminal blockDigging Earth pit and getting ready the earthing arrangementChecking for the compliance of pre commissioning check listPlacing the unit along with related PCB modules/cards and Display moduleConnecting earth terminal of the unit chassis to the main chassis and on to the main earth through copper cables

G.G.Tronics SSDAC

Installation Procedure ContdPlacing Relay box adjacent to the unitFixing of the MS Coupler cable assemblies on to the designated mating Couplers on the rear panel of the systemChecking continuity and insulation resistance between cable pairs and also between the chassis and the cablesConnecting all the shields and the screen wires to the earthFixing of the reset box in a convenient location in the stationConnecting the wires coming from the system to the reset box Connecting 24V DC to power supplyConnecting the power cables coming from the system to the source of power supply of 24V DC at the station, keeping the FTB connector openG.G.Tronics SSDAC

Maintenance:PeriodicityMaintenanceWeeklyCheck for the proper voltage at the battery source for the unitFortnightlyCheck and record the readings ofPower supply module PD moduleCheck the coil Voltages Half yearly / YearlyReplace defective parts if anyEvery 5 YearsPower Supply/DC-DC Converter modulesmust be replaced

G.G.Tronics SSDAC

Back Up Spares RequiredSl.NoSSDAC SparesQuantity1Phase Detector modules1&2 (PD1 and PD2)22CPU1 and CPU2 Modules23Communication Modules24Relay drive Module15Event Logger/SM-CPU Module16DC-DC converter Module17Axle detectors 21 KHz/25KHz (TX coil)28Axle detectors 21 KHz/ 25 KHz (RX coil)29Hardware for mounting axle detectors110MS circular connectors (6 No.)111Reset box RB112SSDAC unit (housing with mother board, without modules)113 Relay Box1

G.G.Tronics SSDAC

Recommended ToolsSl.NoToolsQuantity1PC/Laptop for downloading event logger data for analysis and report generation12Pure sine wave Digital Multimeter (Fluke make 187 or Rishab make 28S or similar13Train simulator14Extender module15Dummy wheel16Ring spanner 17-19,24-2617Open end spanner 17-19, 24-2618Socket spanner with handle19Torque wrench110Screw Driver No. 902111Screw Driver No. 935112Marking jig for drilling1

G.G.Tronics SSDAC

DOs :Sl.NoDOs1The interconnection drawings are to be followed for connecting the Transmitter and Receiver Coils. Tx1 is 21 KHz, Tx2 is 25 KHz & Rx1 and RX2 coils are 21 KHz & 25 KHz, respectively2Ensure that Receiver and Transmitter coil cables are laid in different pipes.3Ensure that both the TX coils & RX coils are having proper alignment on Rail.4Ensure that packing of sleepers with ballast on both sides of Axle detector is proper5Check that metal sheaths of the outdoor cable are connected to earth at both ends6The recommended cables for wiring of the system at site should be used7The steady battery voltage 24 V should be maintained.8The cable connections should not be loose9The M.S Coupler connectors of SSDAC are checked and maintained firmly.10Preparatory Reset should be done only after ensuring that there is no train11It is recommended that heat resisting paint to be used on the apparatus case so that thetemperature inside apparatus case is maintained lower in comparison to other normal paints

G.G.Tronics SSDAC

DONTs:Sl.NoDONTs1Dont cut or join the Transmitter/Receiver cables supplied along with the coil. It would result in change of levels of signals.2Dont remove the modules from SSDAC Units under POWER ON condition of system. Remove module if necessary after switching OFF the power to the Unit.3Local Address of the CPU-1 and CPU 2 and configuration settings of the system should not be changed at the field as far as possible.4The hardware of Communication module and Relay Drive module are similar for all systems. However their positions of mounting is different in different unit types. These modules have to be equipped correctly after verifying the drawings as mentionedin the installation manual (DRG-1 to DRG-4) which indicates their positions5Caution Board has to be placed near the SSDAC Axle detectors to avoid damage to theCoils from packing machines

G.G.Tronics SSDAC

Trouble Shooting:For ease of maintenance in the field messages are provided in the Display Module both during healthy and Error conditionsAbout 61 possible conditions have been identified which drives the system into Error mode.The errors are displayed in plain English on the Display ModuleFurther slides indicate the messages, their analysis and the corrective action to be takenG.G.Tronics SSDAC

Trouble Shooting:Error Code ondisplay of CPUErrorsAnalysisCorrective measure1PD1_BOARD_MISSINGError occurred due to missing of the Phase detector 1 module (PD1- 21KHz) during run time and boot time diagnosis.Place the PD1 module in the slot and reset the system2PD2_BOARD_MISSINGError occurred due to missing of the Phase detector 2 module (PD2- 25KHz) during run time and boot time diagnosis.Place the PD1 module in the slot and reset the system3SM_CPU_MISSINGError occurred due to missing of the SM-CPU module during run time and boot time diagnosis.Place the SM-CPU module in the slot and reset the system4MODEM_MODULE_A_MISSINGError occurred due to missing of the Communication A module during run time and boot time diagnosis.Place the Communication A module in the slot and reset the system5MODEM_MODULE_B_MISSINGError occurred due to missing of the Communication B module during run time and boot time diagnosisPlace the Communication B module in the slot and reset the system6RELAY_DRIVE_A_MISSINGError occurred due to missing of the Relay Drive A module during run time and boot time diagnosisPlace the Relay Drive A module in the slot and reset the system7RELAY_DRIVE_B_MISSINGError occurred due to missing of the Relay Drive B module during run time and boot time diagnosisPlace the Relay Drive B module in the slot and reset the system

G.G.Tronics SSDAC

Trouble Shooting:8PEER_CPU_MISSINGError occurred due to missing of the any one of the CPU module during run time and boot time diagnosisPlace the CPU module missing in the slot and reset the system9COMM_LU1_TO_US1_FAILUREWhen EF CPU1 could not transmit to remote unit (CF or SF) CPU1Check the communication links (MS Coupler) and Reset the system10COMM_LU1_TO_US2_FAILUREWhen EF CPU1 could not transmit to remote unit (SF or CF) CPU2Check the communication links (MS Coupler) and Reset the system11COMM_LU1_TO_DS1_FAILUREWhen SF CPU1 could not transmit to remote unit (CF or EF) CPU1Check the communication links (MS Coupler) and Reset the system12COMM_LU1_TO_DS2_FAILUREWhen SF CPU1 could not transmit to remote unit (CF or EF) CPU2Check the communication links (MS Coupler) and Reset the system13COMM_US1_TO_LU1_FAILUREWhen EF CPU1 could not receive any response from the remote unit (SF or CF) CPU1Check the communication links (MS Coupler) and Reset the system14COMM_US2_TO_LU1_FAILUREWhen EF CPU2 could not receive any response from the remote unit (SF or CF) CPU1Check the communication links (MS Coupler) and Reset the system15COMM_DS1_TO_LU1_FAILUREWhen SF CPU1 could not receive any response from the remote unit (CF or EF) CPU1Check the communication links (MS Coupler) and Reset the system

G.G.Tronics SSDAC

Trouble Shooting:16COMM_DS2_TO_LU1_FAILUREWhen SF CPU2 could not receive any response from the remote unit (CF or EF) CPU1Check the communication links (MS Coupler) and Reset the system17COMM_LU2_TO_US1_FAILUREWhen EF CPU2 could not transmit to remote unit (SF or CF) CPU1Check the communication links (MS Coupler) and Reset the system18COMM_LU2_TO_US2_FAILUREWhen EF CPU2 could not transmit to remote unit (SF or CF) CPU2Check the communication links (MS Coupler) and Reset the system19COMM_LU2_TO_DS1_FAILUREWhen SF CPU2 could not transmit to remote unit (CF or EF) CPU1Check the communication links (MS Coupler) and Reset the system20COMM_LU2_TO_DS2_FAILUREWhen SF CPU2 could not transmit to remote unit (CF or EF) CPU2Check the communication links (MS Coupler) and Reset the system21COMM_US1_TO_LU2_FAILUREWhen EF CPU1 could not receive any response from the remote unit (SF or CF) CPU2Check the communication links (MS Coupler) and Reset the system22COMM_US2_TO_LU2_FAILUREWhen EF CPU2 could not receive any response from the remote unit (SF or CF) CPU2Check the communication links (MS Coupler) and Reset the system23COMM_DS1_TO_LU2_FAILUREWhen SF CPU1 could not receive any response from the remote unit (CF or EF) CPU2Check the communication links (MS Coupler) and Reset the system

G.G.Tronics SSDAC

Trouble Shooting:24COMM_DS2_TO_LU2_FAILUREWhen SF CPU2 does not receive any response from the remote unit (CF or EF) CPU2Check the communication links (MS Coupler) and Reset the system25MODEM_ERROR_NO_CARRIERCarrier signal is being blocked by modemReplace the faulty module26PEER_CPU_LINK_FAILUREError occurred due to missing or error in CPU/ SM-CPU module during run time and boot time diagnosisCheck for the error or presence of SM-CPU/CPU module in the system, rectify the error and reset the system27FAILURE_AT_DSError at Down stream unitCheck the error at remote unit, rectify the error and reset the system28FAILURE_AT_USError at Up stream unitCheck the error at remote unit, rectify the error and reset the system33PD1_SUP_LOWPD1 module supervisory is low for 3 seconds and TX and RX coils is not connected properlyCheck the PD1 module, coils and reset the system34PD2_SUP_LOWPD2 module supervisory is low for 3 seconds and TX and RX coils not connected properlyCheck the PD2 module, coils and reset the system35PD1_PULSINGError occurs when any one sensor is influenced two or more times.Reset the system36PD2_PULSINGError occurs when any one sensor is influenced two or more times.Reset the system37PD_STATE_MISSINGError occurs when double sensor is influence in the sequenceReset the system

G.G.Tronics SSDAC

Trouble Shooting:38PD_SUP_PULSATINGIf supervisory signals pulsates more than 4 timesReset the system39PD_STATE_FAILError occurs when any state sequence is missingReset the system40PD_NOT_SENSINGError occurs when both the PD modules doesnt sense the wheel for more than 3 timesReset the system41PREPARATORY_RELAY_A_FAILURENo/Improper feedback from Preparatory A relayCheck the connections of Preparatory relay A (PRA) and reset the system42PREPARATORY_RELAY_B_FAILURENo/Improper feedback from Preparatory B relayCheck the connections of Preparatory relay B (PRB) and reset the system43VITAL_RELAY_A_FAILURENo/Improper feedback from Vital Relay A relayCheck the connections of Vital relay A (VRA) and reset the system44VITAL_RELAY_B_FAILURENo/Improper feedback from Vital Relay B relayCheck the connections of Vital relay B (VRB) and reset the system45DIRECT_OUT_COUNTWithout IN COUNT, OUT COUNT registeredReset the system49TRANSIENT_POWER_FAILURE_DS1Power failure at Down stream CPU1Reset the system50TRANSIENT_POWER_FAILURE_DS2Power failure at Down stream CPU2Reset the system51TRANSIENT_POWER_FAILURE_US1Power failure at Up stream CPU1Reset the system52TRANSIENT_POWER_FAILURE_US2Power failure at Up stream CPU2Reset the system

G.G.Tronics SSDAC

Trouble Shooting:57INVALID_NETWORK_ADDRESSWhen CPU address range wrongChange the address settings by using LK10 to LK17 links and reset the system58INCORRECT_CODE_CRCThis is a Boot Up error. When CRC of the code mismatches with the stored CRCRe-program the processor and code memory checksum59INVALID_CONFIGURATIONWhen unit type and address of CPU is wrongChange the address and configuration settings as per the requirement and reset the system60INVALID_COUNTSTrain with 10,000 wheelsReset the system61RAM_TEST_FAILEDThis is an Boot up error when RAM (In- built memory of Microcontroller) is failedReplace the Micro Controller

G.G.Tronics SSDAC

G.G.Tronics SSDAC

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