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Mechanical Gauges



There’s a good reason why FW Murphy is known for its gauges. Let's start with the game changer, the Swichgage®, a diaphragm-actuated, indicating gage with built-in electrical switches for tripping alarms and/or shut-down devices.

These solid, reliable instruments are used on industrial engines and equipment in oil field, marine, irrigation, construction and trucking industries. They dependably monitor engine coolant, crankcase oil and transmission oil. They’re highly accurate and long-lasting.




Mechanical Temperature Gauges

 

 

20T / 25T Series Swichgage®

 

The 20 Series (2 inch/51 mm dial) and the 25 Series (2-1/2 inch/64 mm dial) Swichgage® models are diaphragm-actuated, temperature-indicating gages with built-in electrical switches for tripping alarms and/or shut-down devices.

Ranges are available from 32°-120°F (0°-45°C) through 300°-440°F (160°-220°C).

 

   •  Combination indicating gage and limit switch

   •  Critical/High temperature limit switch is visible and adjustable (most models)

   •  Switch can activate alarms and/or shut down equipment

   •  Contact grounds through the case

 

Click here to see product specifications and current literature.

 

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A20T / A25T Series Swichgage®

 

The A20 Series (2 inch/51 mm dial) and the A25 Series (2-1/2 inch/64 mm dial) Swichgage® models are diaphragm-actuated, temperature-indicating gages with built-in electrical switches for tripping alarms and/or shut-down devices.

Ranges are available from 32°-120°F (0°-45°C) through 300°-440°F (160°-220°C).

 

   •  Corrosion resistant polycarbonate case

   •  Indicating gage and limit switch

   •  Critical/High temperature limit switch is visible and adjustable (most models)

   •  Switch can activate alarms and/or shut down equipment

   •  Contact(s) isolated from ground

 

Click here to see product specifications and current literature.

 

 

 

SDB Series

 

The SDB Series are direct-mounting temperature Swichgage® devices. They provide an accurate direct-reading gage with an adjustable limit switch to activate alarms and/or shutdown. A knob on front of the Swichgage instrument allows you to adjust the limit switch trip point.

Models SDB500, SDB501 and SDB500EX have a temperature range of 100° to 500°F (40° to 260°C). SDB500EX enclosure is explosion-proof and CSA listed for Class I, Group C and D hazardous locations. The SDB1000 has a temperature range of 200° to 1000°F (100° to 500°C).

 

   •  Easy to read dial

   •  Bi-metallic sensor

   •  Dials scaled in degrees fahrenheit / celsius

   •  CSA listed explosion-proof model available

 

Click here to see product specifications and current literature.

 

 

 

SPL & 45TE Series

 

The 4-1/2” (114 mm) size dial Swichgage® is a mechanical gage for temperature indication. It is a combination indicating gage and critical temperature limit switches. High and low temperature limit contacts are visible and adjustable.

It includes adjustable, electrical contacts that can be used for start and stop, to trip alarms and to shut down equipment. Ranges are available from 15° to 250°F (9°° to 121°C) through 260° to 450°F (127° to 232°C).

 

   •  Combination indicating gage and critical temperature limit switches

   •  SPDT snap-acting models

   •  Panel and wall mount versions

   •  Latching control relay versions available

 

Click here to see product specifications and current literature.

 

 


Mechanical Pressure Gauges

 

 

20DP / 25DP / A20DP / A25DP Series Swichgage®

 

The 20DP and A20DP Series (2 inch/51 mm dial) and the 25DP and A25DP Series (2-1/2 inch/64 mm dial) Swichgage® instruments are diaphragm-actuated, differential pressure-indicating gages with a built-in electrical switch. This switch is used for tripping alarms and/or shutting down equipment.

The gage pointer acts as a pressure indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Contacts have self-cleaning motion to ensure electrical continuity. A polycarbonate, break-resistant lens and a polished, stainless steel bezel help protect these rugged, built-to-last instruments.

 

   •  Constant visual indication of the condition of your filter is shown on the dial

   •  Two instruments in one with an accurate indicating gage and adjustable p.s.i.d. limit switch

   •  Adjustable contact lets you set the monitoring range of the gage

   •  The 20DP and 25DP series mechanism is enclosed in a steel case coated to resist corrosion

   •  The A20DP and A25DP series have a polycarbonate case and are sealed from the environment

 

Click here to see product specifications and current literature.

 

 

 

20P / 25P Series Swichgage®

 

The 20 Series (2 inch/51 mm dial) and the 25 Series (2-1/2 inch/64 mm dial) Swichgage® models are diaphragm-actuated, pressure-indicating gages with built-in electrical switches, designed to protect engines/equipment in oil field, marine, irrigation, construction and trucking applications to monitor engine lube pressure, water pump pressure, hydraulic pressure, air pressure, etc.

The gage pointer acts as a pressure indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Contacts are grounded through the case and have self-cleaning motion to ensure electrical continuity. A built-in pulsation dampener helps eliminate pointer flutter and is removable for cleaning.

Ranges are available from 0-15 psi (103 kPa) [1.0 bar] through 0-400 psi (2.8 MPa) [28 bar].

 

Click here to see product specifications and current literature.

 

 

 

20V / 25V / A20V / A25V Series Swichgage®

 

The 20 Series (2 inch/51 mm dial) and the 25 Series (2 1/2 inch/64 mm dial) Swichgage® instruments are diaphragm-actuated, vacuum-indicating gages with built-in electrical switches. These switches are used for tripping alarms and/or shutdown devices.

The gage pointer acts as a pressure indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Commonly used to measure loading of spark-ignition engines through intake manifold vacuum, the gages may serve as overspeed protection from sudden loss of load on these engines. Use anywhere the vacuum source is compatible with port materials.

A pulsation dampener is included with each Swichgage® to help eliminate pointer flutter.

 

Click here to see product specifications and current literature.

 

 

 

A20P / A25P Series Swichgage®

 

The A20 Series (2 inch/51 mm dial) and the A25 Series (2-1/2 inch/64 mm dial) Swichgage® instruments are diaphragm-actuated, pressure-indicating gages with built-in electrical switches for tripping alarms and/or shutdown devices. These rugged instruments are face sealed from the environment by the unique combination of a polycarbonate case and lens, a polished stainless steel bezel and O-ring seals.

The gage pointer acts as a pressure indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Applications include: engines/equipment in oil field, marine, irrigation, construction and trucking for lube oil pressure, water pump pressure, hydraulic pressure, air pressure, etc.

A built-in pulsation dampener helps eliminate pointer flutter and is removable for cleaning. Ranges are available from 0-15 psi (103 kPa) [1.0 bar] through 0-400 psi (2.8 MPa) [28 bar].

 

Click here to see product specifications and current literature.

 

 

 

45APE Series Swichgage®

 

The 45APE Series Swichgage® instrument is a mechanical gage for pressure indication. It includes two adjustable SPDT switches. These snap-acting switches can be used for start and stop, to trip alarms and to shut down equipment.

This model series utilizes a bourdon tube sensing unit with a stainless steel dual-sector geared movement. Each of the sectors drives separate pointers when pressure is applied to the bourdon tube. The series is widely used in applications requiring pressure indication and Form C low and high pressure switches.

Ranges are available from 30° VAC (-100 kPa) [-1 bar] thru 10,000 psi (138 MPa) [1379 bar].

 

   •  Combination indicating gage with independent low and high snap-acting switches

   •  Field-adjustable and highly visible low and high pressure trip point indicators

   •  Dual-sector geared movement allows for full-scale indication and set point control

   •  Panel and surface mount versions available

   •  Latching control relay versions available

 

Click here to see product specifications and current literature.

 

 

OPL Series Swichgage®

 

The OPL-Series Pressure Swichgage® instruments are combination pressure indicating gages with adjustable low and high limit switches. Limit switches can be wired directly to electric pilot circuits to operate alarms, shutdown or the start/stop of engines and electric motors.

All models in the series feature a 4-1/2 in. (114 mm) dial for easy viewing. Adjustable limit switches are accessible from the front of the instrument. Limit contacts have self-cleaning motion to enhance electrical continuity.

 

   •  Combination indicating gage and critical pressure limit switches

   •  High and low pressure limit contacts are visible and adjustable

   •  Panel and surface mount versions

   •  Indicating-only Murphygage® available

   •  Latching control relay versions available

 

Click here to see product specifications and current literature.

 

 

 

PD8100 Series

 

The PD8100 Series eliminates pointer flutter on pressure indicating Swichgage® devices which are subject to pulsating pressure from reciprocating pumps or compressors. It decreases wear on geared movements and allows a close setting of high and low contact points, providing for more accurate pressure indication and control of equipment.

 

PD8100 SERIES IS NOT FOR USE ON OXYGEN OR LIQUID OXYGEN APPLICATIONS.

 

This series has a large diameter valve stem wheel for ease of adjustment and features clearly printed operating instructions. Available in brass, carbon steel, 303 stainless steel or 316 stainless steel to meet pressure and environmental requirements with either 1/2 NPT or 1/4 NPT inlet connections.

 

   •  Used on controllers, instruments and recorders to dampen pressure pulsation

   •  Eliminate gage pointer flutter

   •  Aids in providing more accurate pressure indication

   •  Decreases wear on a gage’s geared movement

 

Click here to see product specifications and current literature.

 

 

 

PXT-K Series

 

The PXT-K Series pressure transmitters are state-of-the-art instruments providing 4-20 mA output. Each pressure transmitter contains a transducer comprised of a piezoresistive silicon chip mounted on a glass-metal feed-through header welded into a stainless steel housing and filled with silicone oil.

The enclosure and all wetted parts are made of 316L stainless steel to comply with NACE MR0175. This rugged instrument has an extremely small temperature error and class-leading EMI/RFI resistance, and can be used in applications such as compressors, engines, process control, liquid level and pumps.

 

   •  4-20 mA output signal

   •  Piezoresistive pressure transmitter

   •  Corrosion resistant construction

   •  High stablity

 

Click here to see product specifications and current literature.

 

 

 

PT167EX Series

 

The Murphy PT167EX is a pressure Swichgage® instrument connected to a threaded pressure diaphragm housing. The 2 NPT, sealed diaphragm housing is attached directly to the Swichgage® connection. The diaphragm housing is filled with a silicone fluid so that pressure against the diaphragm causes the instrument to respond. The housing seals the Swichgage® sensing element from the medium being measured.

Applications include highly viscous liquids such as crude oil on lead line applications, asphalt, sludge, and abrasive materials. The instrument is enclosed in an explosion-proof case and is CSA rated for Class I, Division 1, Groups C and D.

 

Click here to see product specifications and current literature.