Carrier WeatherExpert 48N2 Controls, Start-up, Operation, Service And Troubleshooting Instructions

Also see for WeatherExpert 48N2: Installation instructions Installation instructions Controls, start-up, operation, service, and troubleshooting Installation instructions

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Carrier WeatherExpert 48N2 Controls, Start-up, Operation, Service And Troubleshooting Instructions Manual pdf 234 page image

234APPENDIX G — OPTIONAL MOTORMASTER ® V CONTROLGENERALThis appendix contains instructions for the start-up and ser-vice of the optional Motormaster V (MMV) control on48/50N 75-150 ton units.The Motormaster V control is a motor speed control devicewhich adjusts condenser fan motor speed in response to an ana-log signal from the unit ComfortLink controls. A properly ap-plied Motormaster V control extends the operating range of air-conditioning systems and permits operation at lower outdoorambient temperatures.Location of Motormaster V device is in the unit power box.See the power box component arrangement for details.Configure Motormaster® V Control — TheMotormaster V control is configured for analog control mode.The Motormaster V varies the condenser with an acceptablehead pressure. No additional programming is required. SeeTable P.Table P — Configuration TableThe following ComfortLink control configurations must beset when using a Motormaster V device:• ConfigurationCOOLM.M. = YESTest Motormaster V Control — To test the control andmotor, see Service Test section.START-UPThe Motormaster V electronic control will be powered upas long as unit voltage is present. When the system calls forcooling, the Motormaster relay (MMR) will be energized toinitiate the start-up sequence for the Motormaster V electroniccontrol. The LED (light-emitting diode) will display the speedof the motor. The display range will be 8 to 60 Hz. The Motor-master V electronic control will start the condenser fan whenthe compressor engages. The ComfortLink controls will adjustthe fan speed via the Motormaster V electronic control to main-tain approximately 320 psig. Above that pressure, the fanshould operate at full speed.For all units, two Motormaster V devices are used, one foreach circuit. See Fig. M for typical Motormaster V wiring de-tails. See Static Pressure Control section for details.No field programming is required. If controller does notfunction properly, the information provided in the Trouble-shooting section can be used to program and troubleshoot thedrive.NOMINALVOLTAGE(V-Ph-Hz)MODE CONTROL INPUT(Pin 5)STARTCONTACTS230-3-60460-3-60575-3-601Internal PI control,0-5V feedbackTB 1,2208-3-60380-3-60 2 TB 13A,2400-3-50 4 TB 13C,2OFM6 (75)OFM5 (90,105,120 STD-EFF)OFM8 (90,105,120,130 HI-EFF)OFM8 (130,150 STD-EFF)Fig. M — Motormaster ® V WiringLEGENDCCB — Control Circuit BreakerMMF — Motormaster V FusesMMR — Motormaster V RelayMMV — Motormaster V ControlOFM — Outdoor-Fan MotorSCCR — Short Circuit Current Ratinga48-8723