Murphy 25PWC, 20PWC, A25PWC User Manual

Low Pressure SWICHGAGE

®

FRANK W.

MFR.

PHASED-OUT

PWC-94125B

Revised 02-97

Catalog Section 05

(00-02-0033)

®

20PWC, 25PWC and A25PWC Series

20PWC-10

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
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 cor­rosion. 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 polycar­bonate case and includes a 2-1/2 in. (64 mm)
diameter dial.

All gages feature a polycarbonate, break­resistant lens and a polished, stainless steel
bezel to help protect these rugged, built-to­last instruments.

The PWC series is available in either the
SWICHGAGE
and/or low switch contact(s) or in the indi­cating MURPHYGAGE

The SWICHGAGE
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.

®

version with adjustable high

®

incorporates an accurate

®

instruments

®

configuration.

Specifications

Ranges:

20PWC Series

•

0-4 in. H2O; single scale

•

0-10 in. H2O; single scale

•

0-20 in. H2O / 0-51 cm; dual scale

•

0-30 in. H2O / 0-76 cm; dual scale

•

0-50 in. H2O / 0-127 cm; dual scale

25PWC and A25PWC Series

•

0-30 in. H2O / 0-76 cm; dual scale

•

0-50 in. H2O / 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.

2 and 2-1/2 in. (51 and 64 mm) Dial

■

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

®

Wiring (SWICHGAGE

•

20PWC Series: One point,

#6 terminal block, case ground.

•

25PWC Series: Wire lead; 18 AWG x
12 in. (1.0 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).

2

x 305 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.

Only):

Dimensions

A

D

C

1/16 Hex for Limit Switch
Contact Adjustment

Limit Switch
Contact

Contact

Pointer

Mounting

Clamp

Contact Wiring (SWICHGAGE

®

models only)

• 20PWC Series: #6 one-point terminal block

• 25PWC Series: 18 AWG x 12 in.

(1.0 mm2 x 305 mm)

• A25PWC Series: #6 terminal block

1/8-27 NPTM
Connection

Mounting Hole

B

®

FRANK W.

MFR.

PHASED-OUT

Internal Wiring

20PWC Series 25PWC Series A25PWC Series

A 2-7/32 (56) 2-1/8 (54) 1-51/64 (46)
B 1-5/16 (33) 1-3/8 (35) 1-27/64 (36)
C 2-15/64 (57) 3-1/8 (79) 2-29/32 (74)
D 2-1/16 (52) 2-11/16 (68) 2-11/16 (68)

NOTE: Dimensions are in inches and (millimeters).

How to Order

Contact Rating: 2 Amps @ 30 VAC/DC.
20PWC and 25PWC are case ground.
A25PWC is isolated ground.

To order, use the diagram below. NOTE: List options in ascending alphabetical order (A-Z). Example: 20PWC-H-10.

_____ – _____ – _____

Base Model

20PWC
20PWCG

(Gage-only, no contacts)

25PWC*
25PWCG

(Gage-only, no contacts)*

A25PWC*
A25PWCG

(Gage-only, no contacts)*

*25 Series and A25 Series available in 0-30 in.

(0-76 cm) and 0-50 (0-127 cm) ranges only.

Options

†

B1 = Black bezel; low profile
B2 = Bezel; raised profile (was “HP”)
B3 = Black bezel; raised profile (was “HBB”)
EX = Explosion-proof
EL = Explosion-proof, less case
H = High contact only (as optional)

†

Options not available on all models or configurations.

Range

4 = 0-4 in. (0-10 cm)
10 = 0-10 in. (0-25 cm)
20 = 0-20 in. (0-51 cm)
30 = 0-30 in. (0-76 cm)
50 = 0-50 in. (0-127 cm)

HL = High and low contacts (as optional)
I = Illumination
J = Screwdriver adjustable face contact
K = Knob adjusting face contact
RP = Red tipped pointer
TP = Tamperproof contact

In order to consistently bring you the highest quality, full featured products, we reserve the right to change our specifications and designs at any time.

■ Frank W. Murphy Manufacturer

P.O. Box 470248; Tulsa, Oklahoma 74147; USA

tel. [phone] fax[phone]
e-mail [e-mail]

■ Frank W. Murphy Southern Division

P.O. Box 1819; Rosenberg, Texas 77471; USA

tel. [phone] fax [phone]
e-mail [e-mail]

Printed in U.S.A.

Since 1939

■ Frank W. Murphy, Ltd.

Church Rd.; Laverstock, Salisbury SP1 1QZ; U.K.

tel. [phone] fax [phone] tlx 477088
e-mail [e-mail]

■ Frank W. Murphy Pte., Ltd.

26 Siglap Drive; Republic of Singapore 456153

tel. [phone] fax [phone]
e-mail [e-mail]

■ Murphek Pty., Ltd.

1620 Hume Highway; Campbellfield, Vic 3061; Australia
tel. [phone] fax [phone]

■ Murphy de México, S.A. de C.V.

Blvd. Antonio Rocha Cordero 300, Fracción del Aguaje
San Luis Potosí, S.L.P.; México 78384

tel. [phone] fax [phone]
e-mail [e-mail]

■ Murphy Switch of California

P.O. Box 900788; Palmdale, California 93590; USA

tel. [phone] fax [phone]
e-mail [e-mail]

■ Frank W. Murphy France

tel. [phone] fax [phone]