Carrier PC 111 Operating And Troubleshooting Manual

Also see for 48FK034: Controls operation and troubleshooting

52Test under the following conditions:• No power to IN1 or IN2Terminal 1 to 2 should read 4.5 vdc ±0.1 vTerminal 2 to 3 should read 5.0 vdc ±0.1 v• Power to IN2 or to both IN1 and IN2, and P2 set at 24%Terminal 1 to 2 should read 1.5 vdc ± 0.1 vNOTE: Voltage should vary between 0.5 vdc and 2.5 vdc asthe setting of P2 is varied between 0% and 49%.Terminal 2 to 3 should read 5.0 vdc ± 0.1 v• Power to IN1 only and P1 set at 50%Terminal 1 to 2 should read 2.5 vdc ± 0.1 vTerminal 2 to 3 should read 5.0 vdc ± 0.1 vNOTE: Voltage should vary between 0.5 vdc and 2.5 vdc asthe setting of P2 is varied between 50% and 100%.NOTE: If the voltages listed in these 3 tests are not ob-tained during testing, the DLCM board must be replaced.Enthalpy Sensor Checkout — To test operation ofenthalpy sensor, see Table 29.Table 29 — Enthalpy Sensor CheckoutEconomizer Motor — All control of the motor (i.e.,enthalpy changeover, minimum position control and mixed aircontrol) is accomplished from the main unit microprocessorthrough a relay board. Service and installation instructionsfor the unit should be consulted to verify proper operation ofthese controls. The economizer motor may be checked out sep-arately. See Fig. 52 for VAV economizer motor connectioninformation.Motor TestApply 24 volt AC power to terminals T1 and T2 of motor.Connections to motor terminals 2 and 3 must be disconnectedA Motor Test A Expected Result and ResponseJumper 1 to Motor drives open; if not, 2 at motorreplace motor.B Motor Test B Expected Result and ResponseJumper 1 to Motor drives closed; if not,3 at motor replace motor.Supply Fan Variable Frequency DriveNOTE: The VFDs (part no. TOSVERT130-E3) are speciallymodified for use on Carrier equipment. Some specificationsand control configuration defaults for Carrier applications willdiffer from the VFD manufacturer manual included in thepacket. See Table 30 for listing of Carrier-specific defaultvalues.TEST EXPECTED RESULTAND RESPONSEOutdoor-air sensor:Enthalpy sensor + terminalshould be connected to +terminal on motor. Connect thepositive terminal of a DCmilliammeter to the S terminalof the sensor and the negativeterminal of the meter to S Oterminal of the enthalpy board.Milliammeter reading should bebetween 3 and 24 mA if sensoris operating correctly. If readingis 0 mA, the sensor is eitherwired backwards or is defective.Indoor-air sensor:Enthalpy sensor + terminalshould be connected to +terminal on motor. Connect thepositive terminal of a DCmilliammeter to the S terminalof the sensor and the negativeterminal of the meter to S Rterminal of the enthalpy board.Milliammeter reading should bebetween 3 and 24 mA if sensoris operating correctly. If readingis 0 mA, the sensor is eitherwired backwards or is defective.Factory-installed optional VFD is located near the supplyfan and motor. During any service work or programming atthe VFD, operation of the fan and motor is not desirable.Either disable the supply fan or install an accessory VFDremote display.BLUREDYELAUX. SWITCHLIMIT SWITCHESCAPACITORCWWINDING(OPEN)CCWWINDING(CLOSE)CWFEEDBACKPOTENTIOMETERECONOMIZERMOTORBRAKEWINDING132T1T21123LEGENDFig. 53 — Damper Motor Connection Diagram (VAV)CCW — CounterclockwiseCW — Clockwise