High Pressure Switch and Lockout Sequence
If the high pressure switch opens, the compressor contactor will
Low Pressure Switch, Bypass, and Lockout Sequence
If the low pressure switch opens for more than 120 seconds, the compressor contactor will
Alarm Relay Output
Alarm terminal is output connection for applications where alarm relay is employed. This terminal is powered whenever compressor is locked out due to HPC or LPC sequences as described.
NOTE: Both high and low pressure switch controls are inherently automatic reset devices. The high pressure switch and low pressure switch cut out and cut in settings are fixed by specific air conditioner or heat pump unit model. The lockout features, both soft and manual, are a function of the Compressor Control Module.
ADJUSTMENTS
Adjustable Delay on Make and Delay on Break Timer
The potentiometer is used to select Delay on Break time from 30 seconds to 5 minutes. Delay on Make (DOM) timing on
0.5 minute | (30 seconds) | DOB = 123 second DOM |
1.0 minute | (60 seconds) | DOB = 126 second DOM |
2.0minute (120 seconds) DOB = 132 second DOM
3.0minute (180 seconds) DOB = 138 second DOM
4.0minute (240 seconds) DOB = 144 second DOM
5.0minute (300 seconds) DOB = 150 second DOM
During routine operation of the unit with no power interruptions the compressor will operate on demand with no delay.
Typical Settings for Dual Unit Installation:
Unit 1: DOB set at 2 minutes, and DOM is 132 seconds.
Unit 2: DOB set at 4 minutes, and DOM is 144 seconds.
PHASE MONITOR
All units with three phase scroll compressors are equipped with a 3 phase line monitor to prevent compressor damage due to phase reversal.
The phase monitor in this unit is equipped with two LEDs. If the Y signal is present at the phase monitor and phases are correct the green LED will light.
If phases are reversed, the red fault LED will be lit and compressor operation is inhibited.
If a fault condition occurs, reverse two of the supply leads to the unit. Do not reverse any of the unit factory wires as damage may occur.
PRESSURE SERVICE PORTS
High and low pressure service ports are installed on all units so that the system operating pressures can be observed. A pressure table can be found later in the manual covering all models. It is imperative to match the correct pressure table to the unit by model number.
Manual