PWC-94125B
Revised 02-97
Catalog Section 05
(00-02-0033)
Low Pressure SWICHGAGE
®
20PWC, 25PWC and A25PWC Series
■
For Monitoring Fuel Gas Pressure or
Engine Crankcase Pressure
■
Actuate Alarm or Shut Down System
When Abnormal Pressure Occurs
■
Combination Indicating Gage and
Critical Limit Switch
Description
The PWC Series SWICHGAGE
®
is excellent
for low pressure applications such as engine
shutdown when fuel gas pressure falls to low
level. Suitable for both natural gas or
methane–these SWICHGAGE
®
instruments
can also be used to monitor high engine
crankcase pressure (order option “H”).
The 20 and 25 series gage mechanism is
enclosed in a steel case coated to resist cor-
rosion. The 20 series has a 2 inch (51 mm)
diameter dial. The 25 series has a 2-1/2 in.
(64 mm) diameter dial.
The A25 series gage has a sealed polycar-
bonate case and includes a 2-1/2 in. (64 mm)
diameter dial.
All gages feature a polycarbonate, break-
resistant lens and a polished, stainless steel
bezel to help protect these rugged, built-to-
last instruments.
The PWC series is available in either the
SWICHGAGE
®
version with adjustable high
and/or low switch contact(s) or in the indi-
cating MURPHYGAGE
®
configuration.
The SWICHGAGE
®
incorporates an accurate
direct-reading gage with a limit switch (low
contact for fuel gas pressure; high contact for
crankcase pressure) that can be adjusted from
the front of the gage. The switch can be used to
activate alarms and/or shut down equipment.
Specifications
Ranges:
20PWC Series
• 0-4 in. H
2
O; single scale
• 0-10 in. H
2
O; single scale
• 0-20 in. H
2
O / 0-51 cm; dual scale
• 0-30 in. H
2
O / 0-76 cm; dual scale
• 0-50 in. H
2
O / 0-127 cm; dual scale
25PWC and A25PWC Series
• 0-30 in. H
2
O / 0-76 cm; dual scale
• 0-50 in. H
2
O / 0-127 cm; dual scale
Contact Rating: 2 A @ 30 Volts AC/DC.
Accuracy: ±3% first and last 1/3 of scale,
±2% middle 1/3 of scale.
Maximum Pressure: 2 x scale.
Process Connection: 1/8-27 NPTM brass.
Dial: White on black; single scale (inches)
and dual scale (inches/centimeters).
Limit Switch Adjustment: 1/16 hex wrench.
Mounting Hole: 2-1/16 in. (52 mm).
Bezel: Polished stainless steel.
Lens: Polycarbonate.
Mounting Studs: 10-32 UNF.
Case:
• 20PWC and 25PWC Series: Plated steel.
• A25PWC Series: Polycarbonate.
Wiring (SWICHGAGE
®
Only):
• 20PWC Series: One point,
#6 terminal block, case ground.
• 25PWC Series: Wire lead; 18 AWG x
12 in. (1.0 mm
2
x 305 mm).
• A25PWC Series: #6 terminal block.
Mounting Clamp: Plated steel.
Shipping Weight:
• 20PWC Series: 9 oz. (279 g).
• 25PWC and A25PWC Series:
11 oz. (342 kg).
Shipping Dimensions:
• 20PWC Series:
3 x 2-3/4 x 2-3/4 in. (76 x 70 x 70 mm).
• 25PWC and A25PWC Series:
4-3/4 x 4-3/4 x 2-3/4 in. (121 x 121 x 70 mm).
Warranty
A two-year limited warranty on materials and
workmanship is given with this Murphy product.
Details are available on request and are packed
with each unit.
2 and 2-1/2 in. (51 and 64 mm) Dial
20PWC-10
®
FRANK W.
MFR.
PHASED-OUT
