10703783 – Murphy Temperature Swichgage – Model A25TG-250-14-1/2


A25TG-250-14-1/2: 2.5″ Temperature Swichgage®; Without Contacts; 130-250 Temp Range; 14 Ft Capillary (10703783)

The Mechanical 130-250F Temperature Murphygage 2.5″ with 14 Ft Capillary A25TG-250-6-1/2 by Murphy is diaphragm-actuated, temperature-indicating gage without contacts/switch. This rugged, built-to-last instrument is fully sealed from the environment by the unique combination of a polycarbonate case and lens, a polished stainless steel bezel and O-ring seals. This vapor actuated gauge features a sealed capillary tube and a sensing bulb. When subjected to heat, the liquid in the sensing bulb changes to vapor creating pressure against a diaphragm mechanism. The diaphragm translates this vapor pressure into a mechanical gage reading.

Applications for A25 series temperature swichgage instruments include: engines and equipment in oil field, marine, irrigation, construction and trucking industries. Monitoring engine coolant temperature, crankcase oil and transmission oil.

Estimate available in 42 working days from Italy to Italy.

This product may vary on delivery times, as factories do not guarantee production due to lack of raw materials.

Availability: Available on backorder SKU: 10703783 Categories: , Tags: ,


Product Specifications:

  • Dial: White on black; U.S.A. standard scale is dual scale °F/°C; others available (see How to Order)
  • Case: Glass filled/Polycarbonate, corrosion-resistant; steel mounting clamp included
  • Bezel: Polished stainless steel, standard; others available
  • Pointer: Tempered nickel silver; red tip
  • Lens: Polycarbonate, high impact
  • Sensing Element: Beryllium copper diaphragm.
  • Capillary: PVC armored copper; 14 ft. (4,2 m) Stainless steel armor optional
  • Sensing Bulb: Copper
  • Gage Accuracy: See Temperature Accuracy Chart
  • Maximum Temperature: 130° – 250°F (54° – 121°C)
  • Adjustable limit Contact: SPST contact; pilot duty only, 2 A @ 30 VAC/ VDC; Ground path through encasement. Normally Closed (NC) when the high limit is met. Normally Open (NO) when pointer is in normal operating range. Contacts are gold flashed silver
  • Limit Contact Adjustment: By a 1/16 in. hex wrench through 100% of the scale
  • Unit Weight: A25 Series: 13.3 oz. (0.413 kg)
  • Unit Dimensions: A25 series: 4-3/4 x 4-3/4 x 2-3/4 in. (121 x 121 x 70 mm)


a25 series models dimension

Temperature Ranges and Factory Settings


  1. Values in () are amtematical conversions from °F to °C – They not reflect actual second scale range. U.S.A. standard scale is °F/°C.
  2. For models A20TE and A25TE; the switch trip point cannot be set at either the low or high extreme of the scale. The trip point must allow for the reset differential. Only certain models are adjustable.
  3. For adjustable models, the trip point is adjustable only over the upper half of the scale.

temperature ranges factory settings a20 series murphy

temperature accuracy chart a20 series murphy

Magnetic Switch

Inductive and high current loads require the use of a magnetic switch. The swichgage contacts are for light-duty electrical switching to operate alarms or control devices. Enovation Controls Manufactures Switch for protection of the pilot-duty Swichgage limit contacts.
Tattletale® Magnetic Switches show the cause of shutdown for applications that include: capacitor discharge or magneto ignitions, battery systems and electric motor driven equipment. Typical wiring diagrams are shown.

magnetic switch a20 series murphy

Pre-Alarm using A20/A25TABS

The A20TABS and A25TABS feature a standard limit contact for equipment shutdown on high temperature and an internal SPDT snap-switch to signal an alarm before shutting down. When the snap-switch trips (preset point) on rising temperature, the switch completes a circuit to activate an alarm.
If the temperature continues to increase, the face-adjustable pointer contact will make and the shutdown circuit will be completed (see the typical diagram). The front contact shutdown limit setting (which is adjustable) and the snap-switch are preset at the factory. Refer to Temperature Ranges and Factory Settings table for settings. For alternative alarm before shutdown, see Magnetic Switch model 760A or 761APH.

pre-alarm using a20 a25tabs murphy

How to order:

  • Base Model: A25TG
  • 250 = 130° – 250°F (54° – 121°C)
  • 14 = 14 feet = 4,2 m
  • Adapter Nuts = 1/2

20t a20t 25t a25t series thermowells

20t a20t 25t a25t series thermowells

20t a20t 25t a25t series thermowells

Additional information

Weight0,41 kg


10703783, A25TG-250-14-1/2