Manual 2100-526H
Page
16 of 24
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.
MOTOR START DEVICE
Single Phase (-A) model compressor circuits are
equipped with a 25 ohm PTCR (Positive Temperature
Coefficient Resistor) motor starting device as standard
equipment.
The PTCR is wired in parallel with the run capacitor.
When voltage is applied, and device is cool, its low
resistance permits a large current to flow in the
auxiliary windings - increasing the motors available
starting torque. The device then rapidly heats up,
and the current levels drop to a few milliamperes.
The PTCR then becomes self-regulating, passing just
enough current to maintain its temperature to remain
in the high resistance state. Once the voltage source is
removed, the device then cools down and the resistance
drops, and is then ready for the next compressor start
cycle.
PRESSURE SERVICE PORTS
High and low pressure service ports are installed on
all units so that the system operating pressures can be
observed. Pressure tables 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.
Be careful to observe whether unit is operating in high
cool or low cool when utilizing the charts.
This unit employs high-flow Coremax valves instead of
the typical Shrader type valves.
WARNING! Do NOT use a Schrader valve core removal
tool with these valves. Use of such a tool could result in
eye injuries or refrigerant burns!
To change a Coremax valve without first removing the
refrigerant, a special tool is required which can be
obtained at www.fastestinc.com/en/SCCA07H. See the
replacement parts manual for replacement core part
numbers.
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 power-up and after power interruptions is
equal to 2 minutes plus 10% of Delay on Break (DOB)
setting:
0.5 minute (30 seconds) DOB = 123 second DOM
1.0 minute (60 seconds) DOB = 126 second DOM
2.0 minute (120 seconds) DOB = 132 second DOM
3.0 minute (180 seconds) DOB = 138 second DOM
4.0 minute (240 seconds) DOB = 144 second DOM
5.0 minute (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.
T
ypical 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
