4
P70, P72, P170 Series Controls for High Pressure Applications Installation Instructions
Table 1: Pressure Control Switch Action, Low Events, High Events, Model Types, and Electrical Ratings
Tables References
Switch and Action
Low Event
High Event
Model Types - Electrical
Rating Table References
Single-Pole Single-Throw
(SPST) Open-Low
Cutout
(Opens Line to M1)
Cut In
(Closes Line to M1)
P70A, P70B, P170A
See Table 3.
Single-Pole Single-Throw
(SPST) Open-High
Cut In
(Closes Line to M1)
Cutout
(Opens Line to M1)
P70C, P70D, P170C, P170D
See Table 3.
Single-Pole Double-Throw
(SPDT)
Opens 1 to 2 and
Closes 1 to 3
Closes 1 to 2 and
Opens 1 to 3
P70E, P70F
See Table 4.
4-Wire, 2-Circuits,
1-NO, 1-NC
Open-Low
Cutout
(Opens M2 to Line and
Closes M1 to Line)
Cut In
(Closes M2 to Line and
Opens M1 to Line)
P70G, P70H
See Table 5.
4-Wire, 2-Circuits,
1-NO, 1-NC
Open-High
Cut In
(Closes M2 to Line and
Opens M1 to Line)
Cutout
(Opens M2 to Line and
Closes M1 to Line)
P70J, P70K, P170K
See Table 5.
Double-Pole Single-Throw
(DPST)
Open-Low
Cutout
(Opens M1 to Line and
M2 to Line)
Cut In
(Closes M1 to Line and
M2 to Line)
P72A, P72B
See Table 6.
(DPST)
Open-High
Cut In
(Closes M1 to Line and
M2 to Line)
Cutout
(Opens M1 to Line and
M2 to Line)
P72C, P72D
See Table 6.
Adjustments
Adjustments of the P70, P72, and P170 high
pressure controls vary, depending on the model.
The following guidelines and diagrams illustrate the
procedures for adjusting these controls. Refer to the
product label inside the control cover for model
number and switch action. Refer to Table 1 for
switch action, low event, and high event for the
various control models.
High Pressure Cutout - Automatic Reset
High pressure Cutout controls with automatic reset
have a scaleplate that displays the Cut In and
Cutout setpoints. (See the visible scale on the
control.) Turn the range screw to adjust the Cut In
and Cutout setpoints up or down simultaneously,
while maintaining a constant pressure differential.
Turn the differential screw to adjust (only) the low
event on the left side of the scale (which changes
the differential pressure value).
High Pressure Cutout - Manual Reset Lockout
High pressure Cutout controls with the Manual
Reset Lockout option have a scaleplate that displays
the Cutout setpoint. There is no pointer for the Cut In
setpoint. (See the visible scale on the control.)
Turn the range screw to adjust the Cutout setpoint
on the right side of the scale. There is no differential
screw on Manual Reset Lockout models. The differential
pressure value is fixed.
Condenser Fan Cycling - Open-Low Switch Action
Condenser fan cycling pressure controls have a
scaleplate that displays the Cut In
setpoint
and
Differential setting. (See visible scale on the control.)
Turn the range screw to adjust the Cut In setpoint on the
right side of the scale. Turn the differential screw to
adjust the Differential setting on the left side of the scale
(which changes the Cutout pressure value).
IMPORTANT:
Do not adjust pointers beyond the
highest or lowest indicator marks on the control’s
pressure scale. Adjusting pointers beyond indicator
marks may damage screw threads, may cause
inaccurate control operation, and will void the
warranty.
IMPORTANT:
Use the pressure control settings
recommended by the manufacturer of the controlled
equipment. Do not exceed the pressure ratings of the
controlled equipment or any of its components when
checking pressure control operation or operating the
controlled equipment.
