Trane RTWA 70-125 TON User Manual

August 2005 RLC-SVD03A-EN© American Standard Inc. 2005Model RTAA 70-125 TonRTWA 70-125 TonRTUA 70-125 TonDiagnosticTroubleshootingRepairSeries R® 70-1

10 RLC-SVD03A-ENInterprocessor Communication Figure 1 IPC Link Order For 70-125 Ton RTAA*#,$5*-3#0"5*-3#0!

RLC-SVD03A-EN 11Interprocessor Communication.3. Loss of power to a module:Generally a power loss to a particular module will only affect communica-tio

12 RLC-SVD03A-ENInterprocessor Communication5. Improper connections to terminal J2:Jack J2, present on all modules except CLD, should have no connecti

RLC-SVD03A-EN 13Interprocessor Communication3. Determine which modules are still talking. Wiring up to these is likely to be OK.4. Try disconnecting t

14 RLC-SVD03A-ENInterprocessor CommunicationThe CPM has detected loss of communications with MCSP A, MCSP B, and EXV. Suspect an open early in the IPC

RLC-SVD03A-EN 15Temperature Sensor CheckoutWith the exception of the thermostats located in the motor windings of the screw compressors, all the tempe

16 RLC-SVD03A-ENTemperature Sensor Checkout4. Again measure the temperature at the sensor with an accurate thermom-eter; record the temperature readin

RLC-SVD03A-EN 17Temperature Sensor Checkout.1. Overall accuracy for any of the sensors is at least + 2 F over the range shown. Accuracy of matched sen

18 RLC-SVD03A-ENTemperature Sensor Checkout1. Overall accuracy for the sensor is at least + 2 F over the range shown.2. As you compare a thermistor re

RLC-SVD03A-EN 19Compressor OperationThis feature is called the Auto Lead/Lag and can be found in the Service Settings Group, under the “Balanced CPRSR

2 RLC-SVD03A-EN Important - Read This First!This manual is intended for experienced service personnel familiar with the proper use of electrical diagn

20 RLC-SVD03A-ENCompressor Start/StopTo start a compressor after either a “normal' shutdown, a Diagnostic reset, or power-on-reset, the following

RLC-SVD03A-EN 21Variable Speed Inverter/Condenser Fan Control When Fan Control and Variable Speed Fan (VSF) are set to Enable in the Machine Configura

22 RLC-SVD03A-ENVariable Speed Inverter/Condenser Fan Controlspeed will also cause constant speed fans to stage On and Off when the inverter is comman

RLC-SVD03A-EN 23Current TransformerEach compressor motor has all three of its line currents monitored by torroid (doughnut) current transformers. Whil

24 RLC-SVD03A-ENCurrent Transformerwill be displayed. If this protection is disabled, a 30% phase unbalance will still be in effect with the diagnosti

RLC-SVD03A-EN 25Current Transformer  WARNINGHazardous Voltage w/Capacitors!Disconnect all electric power, including remote disconnects before servici

26 RLC-SVD03A-ENCurrent Transformeressary to remove a cap over the top of the connector to gain access to the connector conductors.)6. Refer to Table

RLC-SVD03A-EN 27Current Transformer with all phase currents to the compressors verified to be within their nor-mal range, then the problem is either w

28 RLC-SVD03A-ENCurrent TransformerTable 5 Compressor Overload DIP Switch SettingsCompressorTo n s Volt s/Hz RLAPrimary TurnsThrough Current Transform

RLC-SVD03A-EN 29Current Transformer Table 6 Trip Times Vs. % CurrentMOTOR CURRENT (% RATED RLA) MINIMUMTRIP TIME (SEC) NOMINAL MAXIMUM127.7 or below

RLC-SVD03A-EN 3ContentsGeneral Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Service Philosophy

30 RLC-SVD03A-ENCurrent TransformerTable 8 Compressor Phase Current vs. AC Input Voltage at MCSPACTUAL COMPRESSOR PHASE AMPS THRU CTTERMINALVOLTAGE (V

RLC-SVD03A-EN 31Current Transformer Table 9 Overload Dip Switch Setting vs. Internal Software GainCPRSR RATED RLAAS A % OF CT RATINGOVERLOAD DPSWITCH

32 RLC-SVD03A-ENUnder-Over Voltage TransformerThe hardware required for the Under/Over voltage sensing function of the UCM is standard on the 70-125 T

RLC-SVD03A-EN 33Under-Over Voltage Transformerreplacing the CPM, double check the Under-Over Voltage Function's Nominal Line Voltage Setup in the

RLC-SVD03A-EN 34Compressor CapacityThe 35 to 60 ton helical rotary screw compressors are loaded and unloaded by means of an internal slide valve and a

RLC-SVD03A-EN 35Compressor Capacity Checkout Procedure for MCSP Load/Unload Outputs WARNINGLive Electrical Components!During installation, testing, s

36 RLC-SVD03A-ENCompressor Capacity prevent a compressor from loading even if the chilled water setpoint is not satisfied. Refer to the RTAA-IOM-4 for

RLC-SVD03A-EN 37Compressor Capacity NOTE: Enabling the “Compressor Test” only affects which compressor will be cycled on next and is not an override m

38 RLC-SVD03A-ENCompressor Capacity UnloadNOTE: The following assumes that the compressor's slide valve is already at some loaded position and %R

RLC-SVD03A-EN 39Compressor Capacity pressure, then the Slide Valve is bound.5. If cylinder cavity pressure does not decrease or is at suction pressure

4 RLC-SVD03A-ENGeneral InformationThe Unit Control Modules (UCMs) described in this troubleshooting guide provide a microprocessor based refrigeration

40 RLC-SVD03A-ENCompressor Capacity  WARNINGLive Electrical Components!During installation, testing, servicing and troubleshooting of this product, i

RLC-SVD03A-EN 41Module Power and Miscellaneous I/OThis section will detail the normal voltage levels present on each of the modules inputs and outputs

42 RLC-SVD03A-ENModule Power and Miscellaneous I/OClear Language Display (CLD) 1U6 Keypad OverviewLocal operator interface with the system is accompli

RLC-SVD03A-EN 43Module Power and Miscellaneous I/OSelect Report GroupThis group of four keys allows the operator to select and view the following repo

44 RLC-SVD03A-ENModule Power and Miscellaneous I/OWhen any of the four report keys are pressed, the first readout on the display will be the header. T

RLC-SVD03A-EN 45Module Power and Miscellaneous I/OPress Next to move down through the Chiller Report. As shown in the figures, the flowchart explains

46 RLC-SVD03A-ENModule Power and Miscellaneous I/OWhen updating is successfully completed, the system will default to the first display after the Chil

RLC-SVD03A-EN 47Module Power and Miscellaneous I/OTe s t P o i n t sThere are two test points associated with the CPM module. They are easily read wi

48 RLC-SVD03A-ENModule Power and Miscellaneous I/OI/O terminalsFor the checkout of the I/O, refer to the block diagram of the module in Figure 10 and

RLC-SVD03A-EN 49Module Power and Miscellaneous I/OTable 16 CPM (Chiller) Nominal Terminal Input and Output (1U1)Te r m i n a lDesignationDescriptionof

RLC-SVD03A-EN 5General InformationSystem DescriptionThe CPM is the master module and coordinates operation of the entire system. One is used per chill

50 RLC-SVD03A-ENModule Power and Miscellaneous I/OOptions Module (CSR) (1U2) WARNINGLive Electrical Components!During installation, testing, servicin

RLC-SVD03A-EN 51Module Power and Miscellaneous I/O2. Has its negative terminal tied to chassis ground.If the intended source does not meet the above r

52 RLC-SVD03A-ENModule Power and Miscellaneous I/OSetpoint PriorityThere are many ways in which the Chilled Water and Current Limit setpoints can be a

RLC-SVD03A-EN 53Module Power and Miscellaneous I/O“TRACER” implies Trane Integrated Comfort System remote device (ICS) using the digital communication

54 RLC-SVD03A-ENModule Power and Miscellaneous I/O“TRACER” implies Trane Integrated Comfort System remote device (ICS) using the digital communication

RLC-SVD03A-EN 55Module Power and Miscellaneous I/OICS CommunicationsICS (Tracer) communication is handled the same as on previous products using the T

56 RLC-SVD03A-ENModule Power and Miscellaneous I/OTable 19 CSR Normal Terminal Voltages for Options Module 1U2Te r m i n a lDesignationDescriptionof C

RLC-SVD03A-EN 57Module Power and Miscellaneous I/O° TP1 +5V° TP2 + 6VJ6-1 — 115VAC HOTJ6-2 — 115VAC HOT° TP2 + 12V J6-3 — KEY (N/C)J6-4 — NEUTRALIPC (

58 RLC-SVD03A-ENModule Power and Miscellaneous I/OElectronic Expansion Valve Module (EXV) (1U3) WARNINGLive Electrical Components!During installation

RLC-SVD03A-EN 59Module Power and Miscellaneous I/OA “FLAG” stop is located at either end of the threaded portion of the motor shaft. The stops interfe

6 RLC-SVD03A-ENGeneral InformationHigh Pressure Cutout Switch Low Pressure Cutout Switch Variable Speed Fan Drive Motor Temperature Thermostats Slide

60 RLC-SVD03A-ENModule Power and Miscellaneous I/OElectronic Expansion Valve LocationThe valve should be installed with the motor in a vertical positi

RLC-SVD03A-EN 61Module Power and Miscellaneous I/OTe s t P o i n t sThere is only one test point associated with the EXV module. It is easily read wi

62 RLC-SVD03A-ENModule Power and Miscellaneous I/Odiagnostic suggests that there is a problem with the valve or the valve wiring. To confirm this, it

RLC-SVD03A-EN 63Module Power and Miscellaneous I/O3. Check the resistance from each of the three phase pins (J4-3, J4-2, and J4-1) to the board edge G

64 RLC-SVD03A-ENModule Power and Miscellaneous I/Oused, it is important to direct the flame away from the valve body. See Figure 17. A wet cloth shoul

RLC-SVD03A-EN 65Module Power and Miscellaneous I/O2. Disconnect all the line voltage to the power supply of this unit.3. Refer to the exploded view in

66 RLC-SVD03A-ENModule Power and Miscellaneous I/Oto the valve body until the sealing surfaces make contact. Tighten the actuator approximately 1/8 tu

RLC-SVD03A-EN 67Module Power and Miscellaneous I/OSEHI Electronic Expansion Valve ServicingThe procedures listed below are to. be followed for proper

68 RLC-SVD03A-ENModule Power and Miscellaneous I/O Figure 19 SEHI Electronic Expansion Valve Exploded View-OTOR!DAPTOR!SSEMBLY0ISTON!SSEMBLY"OD

RLC-SVD03A-EN 69Module Power and Miscellaneous I/OSEO Valve Module° TP1 +5V J6-1 — 115VAC HOTJ6-2 — 115VAC HOTJ6-3 — KEY (N/C)J6-4 — NEUTRALIPC (+) —

RLC-SVD03A-EN 7General InformationReal time data for temperatures, diagnostics and control algorithms etc. are made available to the CPM and the other

70 RLC-SVD03A-ENModule Power and Miscellaneous I/OI/0 terminals For the checkout of the I/O, refer to the block diagram of the EXV module in Table 21

RLC-SVD03A-EN 71Module Power and Miscellaneous I/Ospecified, unless otherwise indicated. The first terminal in the pair is the positive (or hot) termi

72 RLC-SVD03A-ENModule Power and Miscellaneous I/OCompressor Module (MCSP) (1U4 AND 1U5) WARNINGLive Electrical Components!During installation, testi

RLC-SVD03A-EN 73Module Power and Miscellaneous I/OBinary InputsThe binary inputs shown in Table 22 all use the same basic circuit. A pullup resistor t

74 RLC-SVD03A-ENModule Power and Miscellaneous I/Othe currents are higher than actual and will show up as an error in the %RLA displayed by the CPM. T

RLC-SVD03A-EN 75Module Power and Miscellaneous I/OI/O TerminalsFor the checkout of the I/O, refer to the block diagram of the MCSP module in Figure 22

76 RLC-SVD03A-ENModule Power and Miscellaneous I/OJ7-8,9 Step Load Solenoid Normally open contact, closes to energize the Step Load Solenoid Valve.J7-

RLC-SVD03A-EN 77Module Power and Miscellaneous I/O° TP1 +5V° TP2 +12VJ6-1 — 115VAC HOTJ6-2 — 115VAC HOTJ6-3 — KEY (N/C)J6-4 — NEUTRALIPC (+) —J1-4 J6-

78 RLC-SVD03A-ENModule Power and Miscellaneous I/OInterprocessor Communication Bridge Module (IPCB) (1U7)The IPCB provides an extension of the IPC lin

RLC-SVD03A-EN 79Module Power and Miscellaneous I/OLonTalk® Communications Interface - Chillers Module(LCI-C) (1U8)The Tracer LCI-C interface acts as a

8 RLC-SVD03A-ENInterprocessor CommunicationsThe respective modules communicate with each other via an InterProcessor Communication link (IPC). The IPC

80 RLC-SVD03A-ENVariable Speed Fan SystemThe purpose of this troubleshooting guide is to help technicians determine if the variable speed fan inverter

RLC-SVD03A-EN 81Variable Speed Fan SystemBus Overvoltage Fault 2Motor Overload Fault 3Low Bus Voltage Fault 4PWM Generator Fault 5Logic Fault 6Stalled

82 RLC-SVD03A-ENVariable Speed Fan SystemTroubleshooting Procedure WARNINGLive Electrical Components!During installation, testing, servicing and trou

RLC-SVD03A-EN 83Variable Speed Fan System.6 VDC. If there is no voltage at either of these two test points, check the incoming 115 VAC between pins J6

84 RLC-SVD03A-ENVariable Speed Fan Systemon at both ends while measuring this voltage. If the reading is between 11.5 and 12.5 VDC, two problems may e

RLC-SVD03A-EN 85Other Service FeaturesService PumpdownThe UCM provides for a "onetime" Service Pumpdown mode, in which a service-technician

86 RLC-SVD03A-ENOther Service Features WARNINGHazardous Voltage w/Capacitors!Disconnect all electric power, including remote disconnects before servi

RLC-SVD03A-EN 87Other Service Featurestioned (if not already controlling). Most often the stage-on will be accom-panied by a controlled stage-off of a

Trane has a policy of continuous product data and product improvement and reserves the right to change design and specifications without notice. Only

RLC-SVD03A-EN 9Interprocessor Communicationfrom the Options Module. When some problem exists with the IPC link or a module fails, it is not uncommon f