Carrier XRV, 19XR specifications Control Modules, Notes on Module Operation

Control Modules

Turn controller power off before servicing controls. This ensures safety and prevents damage to the controller.

The CVC/ICVC, CCM, and ISM modules perform continu- ous diagnostic evaluations of the hardware to determine its condition. Proper operation of all modules is indicated by LEDs (light-emitting diodes) located on the circuit board of the CVC/ICVC, CCM, and ISM.

There is one green LED located on the CCM and ISM boards respectively, and one red LED located on the CVC/ ICVC, CCM, and ISM boards respectively.

RED LED (Labeled as STAT) — If the red LED:

•blinks continuously at a 2-second interval, the module is operating properly

•is lit continuously, there is a problem that requires replacing the module

•is off continuously, the power should be checked

•blinks 3 times per second, a software error has been dis- covered and the module must be replaced

If there is no input power, check the fuses and circuit break- er. If the fuse is good, check for a shorted secondary of the transformer or, if power is present to the module, replace the module.

GREED LED (Labeled as COM) — These LEDs indicate the communication status between different parts of the con- troller and the network modules and should blink continuously.

MODULE PART NUMBER

SOFTWARE PART NUMBER

CVC/ICVC

Notes on Module Operation

1.The chiller operator monitors and modifies configura- tions in the microprocessor by using the 4 softkeys and the CVC/ICVC. Communications between the CVC/ ICVC and the CCM is accomplished through the SIO (Sensor Input/Output) bus, which is a phone cable. The communication between the CCM and ISM is accom- plished through the sensor bus, which is a 3-wire cable.

2.If a green LED is on continuously, check the communica- tion wiring. If a green LED is off, check the red LED operation. If the red LED is normal, check the module address switches (SW1) (Fig. 40 and 41). Confirm all switches are in OFF position.

All system operating intelligence resides in the CVC/ ICVC. Some safety shutdown logic resides in the ISM in case communications are lost between the ISM and CVC/ ICVC. Outputs are controlled by the CCM and ISM as well.

3.Power is supplied to the modules within the control panel via 24-vac power sources.

The transformers are located within the power panel, with the exception of the ISM, which operates from a 115-vac power source and has its own 24-vac transformer located in the module.

In the power panel, T1 supplies power to the compressor oil heater, oil pump, and optional hot gas bypass, and T2 supplies power to both the CVC/ICVC and CCM.

Power is connected to Plug J1 on each module.

CCN INTERFACE	DATALINK OR
CONNECTION	DATAPORT MODULE (OPTION)

BACK OF CVC	J7 SIO	J1 POWER/	J8 SERVICE	SW1
		CCN

Fig. 40 — Rear of CVC/ICVC (Chiller Visual Controller/International Chiller Visual Controller)

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