Johnson Controls System 450 Series Technical Bulletin page 8

The C450CCU condensing unit control module has two relay outputs. For model descriptions
and more information, see
optional expansion module outputs, in the control module UI.
During normal operation, the sensor status screens display on the LCD. The screen autoscrolls,
displaying the temperature and pressure sensors' output readings. Depending on your C450CCU
application, there are several sensor readings available. If the sensor readings display as part of the
standard scrolling, the following sensors are available:
• Sensor 1: Refrigerated space temperature. The time that displays is the current time.
• Sensor 3: The measure of pressure from the pump down pressure transducer.
Note: This value displays only when you configure the pump down or PdWN function.
If the sensor readings are part of the extended LCD status display, the following sensors are
available:
• Sensor 2: The temperature at the defrost termination sensor or the state of the defrost
temperature switch. This value is available when you press the right-arrow in the Normal
status screen.
You can also view the status of all of the outputs in your control system and access the system
setup screens from the main screens in the condensing unit control module UI. The system status
screens display the status of each output in the control system, in addition to the sensor status
screens. A relay output status displays as ON or OFF. For more information, see
condensing unit control
8
Ordering information
system.
System 450 Series C450CCU Condensing Unit Control System Technical Bulletin
Set up the sensors and relay outputs, including
Setting up a