FIGURE 30
8201-164 Compressor Control Module
High Pressure Switch Compressor Contactor Output
Alarm Output
Common
Delay-on-Break Time
Adjustment Potentiometer
Brownout Ignore Time DIP Switches*
18-30 VAC Input
Y Input from Thermostat
and High Pressure Switch
Troubleshooting Light
* Turn on only one switch for that specific ignore time setting
Jumper
Manual 2100-671
Page 22 of 44
Short Cycle Protection/Delay-on-Break
An anti-short cycle timer is included to prevent short
cycling the compressor. This is adjustable from 30
seconds to 5 minutes via the adjustment knob (see Figure
30). Once a compressor call is lost, the time period must
expire before a new call will be initiated.
10% of this time is also considered on the delay-on-
make timer (see Delay-on-Make Timer).
High Pressure Detection
High pressure switch monitoring allows for a lockout
condition in a situation where the switch is open. If the
high pressure switch opens, the CCM will de-energize
the compressor. If the switch closes, it will then restart
the compressor after the delay-on-break setting has
expired on the device. If the switch trips again during
the same Y call, the compressor will be de-energized.
The ALR terminal will be energized, signaling the unit
control board that a high pressure event has occurred
(see Refrigerant High Pressure Alarm on page 23).
Compressor Control Module (CCM)
Delay-on-Make Timer
Short Cycle Protection/Delay-on-Break
Test Mode
High Pressure Detection
Brownout Protection with Adjustment
The LPC terminals are jumpered in this application.
Instead, the low pressure transducer is used for low
pressure monitoring.
Delay-on-Make Timer
In the event of power loss, a delay-on-make timer is
included to be able to delay startup of the compressor.
This is desired when more than one unit is on a
structure so that all of the units do not start at the
same time which could happen after a power loss or
building shutdown. The delay-on-make time period is
2 minutes plus 10% of the delay-on-break time period.
To ensure that all of the units do not start at the same
time, adjust the delay-on-break timer on each unit to a
slightly different delay time.
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