Bard WG3S1-A, Руководство по установке

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Manual 2100-483E
Page 33 of 59
ALARM OUTPUT
Alarm terminal is output connection for applications
where alarm signal is desired. 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 (160 seconds) DOB = 138 second DOM
4.0 minute (240 seconds) DOB = 144 second DOM
5.0 minute (300 seconds) DOB = 150 second DOM
PHASE MONITOR
All units with three phase scroll compressors are
equipped with a three 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.
Optional Low Ambient Control
An optional low ambient control is available for both
factory and field installed options. The low ambient
control is to be applied to the WG3S/WG4S/WG5S
models when operation below 50°outdoor conditions
are anticipated. Without this device, the evaporating
pressure would fall off, and the indoor coil would ice
over.
The fan cycling control cycles the fan motor on, once
the liquid refrigerant pressure reaches 350 psig, and off,
once it has dropped to 225 psig. It will continue to
cycle between these parameters depending on outdoor
temperatures and the load/stage of the system.
This cycling maintains a minimum liquid pressure
affecting the minimum suction pressure. This effect
insures an evaporating temperature that is slightly
above the point of ice formation on the evaporator.
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.