Product Overview

Master Catalog 125
Pressure Controls Section P
Product Bulletin P45
Issue Date 0996
© 1996 Johnson Controls, Inc.
1
Code No. LIT-125445
P45 Series Oil Pressure Cutout Controls
With Built-In Time Delay Relay
Application
The P45 controls provide
dependable economical low lube
oil pressure cutout for pressure
lubricated refrigeration
compressors. The factory set
pressure adjustment provides
operation to the compressor
manufacturer’s specification.
The P45 control measures the
net oil pressure available to
circulate oil through the
lubrication system. (Net oil
pressure is the difference
between the oil gage pressure
and the refrigerant pressure in
the crankcase.)
A built-in time delay relay,
compensated for ambient
temperature, allows for pressure
pickup on start and avoids
nuisance shutdowns on short
duration pressure losses during
the running cycle.
All Series P45 controls are
designed for use
only
as
operating controls. Where an
operating control failure
would result in personal injury
and/or loss of property, it is
the responsibility of the
installer to add devices
(safety, limit controls) or
systems (alarm, supervisory
systems) that protect against,
or warn of, control failure.
Features
•
The P45 is interchangeable
in mounting and wiring with
most Penn P28 controls.
•
Proven reliable pressure
sensing elements -- several
million in use.
•
Time delay relay
incorporates trip-free manual
reset.
Fig. 1 -- Exterior of Series P45.
Power element connection with
1/4 in. flare nut (Style 13) is
standard.
• Ambient compensation gives
uniform time delay
regardless of temperature
variations at control location.
• Enclosed pressure actuated
contacts are protected
against wiring interference.
• Single unit mounting and
wiring -- saves installation
time and materials.
Optional Constructions
Pressure Connectors
Standard controls supplied with
36 in. (914 mm) capillary tubing
with 1/4 in. flare nut (Style 13).
Controls with 1/4 in. SAE male
connector (Style 5) or 36 in.
(914 mm) capillary and 1/4 in.
sweat connection (Style 34) may
be supplied on quantity orders,
when specified. (See Pressure
Sensing Element Styles.)
Specifications