Control Modules; Red Led (Labeled As Stat); Notes On Module Operation - Carrier 19XR User Manual

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.
CVC/ICVC
BACK OF CVC J7 SIO
Fig. 40 — Rear of CVC/ICVC (Chiller Visual Controller/International Chiller Visual Controller)
MODULE PART NUMBER
SOFTWARE PART NUMBER
J1 POWER/ J8 SERVICE
CCN

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
CONNECTION
87
DATALINK OR
DATAPORT MODULE (OPTION)
SW1