Johnson Controls P70 Serie Instrucciones De Instalación

Application
P70, P72, and P170 Series Controls for Low Pressure
Applications provide low-side pressure control on
commercial refrigeration and air-conditioning
applications.
IMPORTANT: Use the P70, P72, and P170
Series Controls for Low Pressure Applications only
as an operating control. Where failure or malfunction
of a P70, P72, or P170 pressure control could lead
to personal injury or property damage to the
controlled equipment or other property, additional
precautions must be designed into the control
system. Incorporate and maintain other devices such
as supervisory or alarm systems or safety or limit
controls intended to warn of, or protect against,
failure or malfunction of the P70, P72, or P170
pressure control.
P70A and P170A type models with Single-Pole
Single-Throw (SPST) Open-Low switch action are the
most popular models and are typically used for
Open-Low operation and pump-down control.
P70 and P170 Series control models are also
available with SPST Open-High switch action and are
typically used for capacity control. Control models with
Single-Pole Double-Throw (SPDT) or 4-wire, 2-circuit
switch action allow users to install alarm devices or
other control circuits.
P72 Series control models have a Double-Pole
Single-Throw (DPST) switch with load-carrying
contacts that provide direct control of 208-240 VAC
single-phase motors up to 3 hp, 480 VAC
single-phase, non-compressor motors, and 208-220
VAC 3-phase motors up to 5 hp. See Table 6.
These controls are available in several pressure
ranges and are compatible with most common
refrigerants. They may also be used on air, water,
and other non-corrosive fluid applications.
Ammonia-compatible models are also available. See
Table 2.
The MICRO-SET® option provides fine adjustment of
the differential setting for precision pressure control of
critical low pressure applications.
© 2006 Johnson Controls, Inc.
Part No. 24-7664-1601, Rev. C
P70, P72, and P170 Series Controls for
Low Pressure Applications
Installation Instructions
Some models are available with Limited Knob
Adjustment, which restricts adjustment of the
pressure settings and deters overadjustment or
tampering. See Limited Knob Adjustment.
The Manual Reset Lockout mechanism does not
allow the control to automatically reset after the control
has Cutout, providing shutdown capability for
unmonitored equipment. See Manual Reset Operation.
NEMA 1 enclosures are standard on most models.
NEMA 3R enclosures are available on select models.
!
CAUTION: Risk of Property Damage.
Mount the pressure control separately from the
electrical cabinet and seal all electrical piping to
prevent ammonia from migrating to electrical
components. Where there may be exposure to
ammonia, use only ammonia compatible control
modules and pressure connections. System
shutdown due to improper adjustment may cause
property damage.
Dimensions
2-Mounting Holes
10-32 UNF-2B
Thread
3-1/4
83
5/16
8
1-7/8
48
3/16
Diameter
3/16
Mounting Hole
5
5
2-1/16
53
15/16
24
1-5/16
34
3-1/16
77
1/16 4
101
2
Figure 1: Dimensions of P70, P72, and P170
Pressure Controls with NEMA 1 Enclosures,
in. (mm)
Issue Date June 12, 2006
5/16
2-13/16
8
71
5/16
8
1
25
1-1/8
29
1-11/16
1-3/4
13/16
44
20
3/16
3/8 3/16
5
X
5
10
Diameter
Mounting Hole
1-1/4
33
(NEMA 1/2 in.)
7/8
22 Conduit Hole
www.johnsoncontrols.com
3-1/4
83
43
1