Product Overview

Note: The compressor contactor circuit
energizes and both the yellow and green
LEDs light up after the short-cycle delay
has expired. The green LED indicates
that the compressor contactor is
energized. The yellow LED indicates that
net oil pressure is low and that the timing
circuit is activated.
When the low pressure time delay
elapses, the control de-energizes (locks
out) the contactor. The red LED lights up
and the yellow and green LEDs turn off.
The control’s alarm contacts (Terminals
CMA to NOA) close and the liquid line
solenoid contacts (Terminals CMA to
NCA) open.
4. Press RESET. The red LED turns off and the
green and yellow LEDs turn on. The contactor is
now energized.
5. De-energize the supply voltage. Reconnect the
compressor leads to the contactor, or reset the
disconnect. If an R310AD switch is used,
reconnect the compressor leads to the contactor.
See
Figure 13.
6. Re-energize the supply voltage. If operating and
limit controls are closed and power has been
removed for longer than the anti-short cycle
delay, the compressor starts and both the green
and yellow LEDs light up. The yellow LED turns
off when the lube oil pressure level reaches the
opening point, usually within seconds of starting
the compressor.
Operational Control Test
Use this test to verify the P545 control is operating
correctly. This test simulates a low oil pressure
condition and initiates an immediate lockout of the
compressor.
1. With power to the control, adequate oil pressure
available, and contactor energized (only the green
LED is on), press and hold down the Test button.
Note: The red LED lights up and the control
de-energizes (locks out) the compressor
contactor. The control alarm circuit (NOA contact –
see
Figure 7) is energized.
2. Wait 100 seconds and press the Reset button to
energize the contactor and restart the motor.
Note: The P545 control cannot be reset without
power. The control remains in a lockout condition
(compressor contactor de-energized) until the Reset
button is pressed, even if power is removed from the
control.
Troubleshooting
See Table 2 to troubleshoot the P545 control.
Table 2: Troubleshooting P545 Control Problems
LED Status Troubleshooting Procedure
No LEDs are lit.
Check the power source.
Red LED is On.
Common
Signal
12011012_plug.cdr
WHA-P400-xxx
Wiring Harness Plug
Use these steps to resolve the problem:
1. Connect pressure gauges at the oil pump discharge and at the crankcase.
2. Press RESET on the control.
a. If the green and yellow LEDs light but the compressor remains off,
inspect the wiring and check for an overheated motor. If the compressor motor is
overheated, determine the cause and correct the problem. (An R310AD current
sensing switch may be installed along with the control to provide a controlled
shutdown caused by thermal overload.)
b. If both the green and yellow LEDs turn on for the duration of the time
delay and the system shuts down, observe the crankcase and oil pump
pressure gauges.
- If the system does not reach sufficient oil pressure by the end of the time
delay, check the compressor and system for problems.
- If the system does reach sufficient pressure:
1. Disconnect the wiring harness at the P400 switch.
2. Use a single piece of 22-gauge wire as a jumper between the common
and signal terminals of the wiring harness.
3. Press RESET.
4. If the green LED lights and the yellow LED turns off, replace the P400
switch. Otherwise, replace the P545 control.
P545 Series Electronic Lube Oil Control Product/Technical Bulletin 9