User Guide

IMPORTANT: The P545 control is intended to
control equipment under normal operating
conditions. Where failure or malfunction of the
control could lead to an abnormal operating
condition that could cause personal injury or damage
to the equipment or other property, other devices
(limit or safety controls) or systems (alarm or
supervisory systems) intended to warn of or protect
against failure or malfunction of the control must be
incorporated into and maintained as part of the
control system.
Low Oil Pressure Timing Circuit Operation
All P545 control timing functions are designed to
comply with compressor manufacturer requirements.
Standard control models de-energize the compressor
contactor if the low-pressure condition lasts longer
than the factory-set time delay.
The oil pressure monitoring circuit on the P545 control
compares the amount of time that the oil pressure is
above opening point to the amount of time that the oil
pressure is below opening point. If the oil pressure is
above opening point more than it is below opening
point, the control does not shut down the compressor.
If the oil pressure drops continuously below the
opening point, the control times out in either 90 or
120 seconds, depending on the model. If the oil
pressure is below opening point more than half of the
time, the control times out but the timing is extended.
This allows the control to protect the compressor when
there are repeated low oil pressure signals interrupted
by short periods of sufficient oil pressure.
R310AD Current Sensing Switch for False Oil
Failure Lockouts
False oil pressure failure lockouts can occur when the
P545 control remains powered despite a loss of power
to the compressor motor (for example, when an
internal motor overload switch trips).
An R310AD switch disables the oil-failure delay timer
when there is no power to the compressor, thus
avoiding false lockouts.
Install the R310AD switch after the main contactor on
one of the compressor power leads, and wire to
terminals W1 and W2 on the P545 control. In addition,
remove resistor R39 by cutting the leads to the circuit
board. See
Figure 13.
IMPORTANT: The R310AD switch does not
work when the control’s anti-short cycle delay timer
is set at 0 seconds. You must set the timer to 35, 65,
or 100 seconds. See Anti-Short Cycle Delay for
further information.
Anti-short Cycle Delay
Anti-short cycle delay establishes the minimum time
that the controlled equipment is de-energized before
restarting. After the P545 control has de-energized the
equipment, the anti-short cycle delay is activated and
the yellow LED lights. The equipment remains
de-energized for the selected amount of delay time.
The anti-short cycle delay on the P545 control may be
set to 0, 35, 65, or 100 seconds.
Backwards Compatibility
The P545 control and P400 switch offer backwards
compatibility with previous offerings in the
Johnson Controls/Penn product line and operate as
shown in
Table 1.
Table 1: Control and Sensor/Switch Compatibility
Test P345 or P445 Control
with P300 Sensor
P345 or P445 Control
with P400 Switch
P545 Control and
P300 Sensor
P545 Control and
P400 Switch
Wiring Harness
1
WHA-P300-xxx Only WHA-P300-xxx or
WHA-P400-xxx
WHA-P300-xxx Only WHA-P300-xxx or
WHA-P400-xxx
Test Switch
6-8 Second Delay
Does not function
2
Immediate Immediate
1. WHA-P300-xxx is the 3-wire harness supplied with the P345 or P445 control and the P300 sensor.
WHA-P400-xxx is the 2-wire harness supplied with the P545 control and the P400 switch.
2. When the P445 control is wired to a P400 switch, The Test button may operate when first powered up; however, after a
couple minutes of operation, the Test Switch function no longer works. All other control functions operate normally.
P545 Series Electronic Lube Oil Control Product/Technical Bulletin 3