25DP and A25DP

Swichgage Series

These 2-1/2 inch differential pressure indicating gauges feature built-in electrical switches for activating alarms and/or shutting down equipment.

  • Visual of filters condition is shown on the dial indicating filter change intervals
  • Accurate indicating gauge and adjustable p.s.i.d. limit switch
  • Adjustable contact lets you set the monitoring range of the gauge
  • Contact is tamper proof
  • Made of durable materials to withstand rugged applications

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  • Overview
  • Specifications
  • Diagrams
  • Literature

The 25DP and A25DP Series (2-1/2 in. /64 mm dial) Swichgage instruments are diaphragm-actuated, differential pressure-indicating gauges with a built-in electrical switch. This switch is used for tripping alarms and/or shutting down equipment. The gauges are intended to monitor and indicate oil, fuel or water filter restriction and can reduce the risk of dangerously high pressure which may rupture the filter, resulting in contaminants entering the system.

The 25DP series mechanism is enclosed in a steel case coated to resist corrosion. The A25DP series has a polycarbonate case sealed from the environment. Both feature a polycarbonate, break-resistant lens to help protect the instruments.

The gauge 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.

Early filter changes cost money and increase the risk of contaminants entering the system. A filter restriction Swichgage instrument lets you know when to change the filter and maintain peak efficiency.

Base Models

25DP and A25DP Swichgage instrument
The gauge pointer makes with an adjustable contact to complete a pilot-duty circuit.

  • Dial: White on black, dual scale; U.S.A. standard scale is psi/kPa; other scales available
  • Case:
    • 25DP Series: plated steel
    • A25DP Series: polycarbonate
  • Bezel: Polished stainless steel, standard; others available
  • Lens: Polycarbonate, high-impact
  • Temperature Range:
    • Ambient: -40° to 150° F (-40° to 66° C)
    • Process: -40° to 250° F (-40° to 121° C)
  • Process Connection: 1/8-27 NPTM brass
  • Sensing Element: Beryllium copper diaphragm
  • Gage Accuracy: ±3% maximum across scale
  • Adjustable Limit Contact: SPST contact; pilot duty only, 2 A @ 30 VAC/DC; closed when the low limit is met, open when pointer is in normal operating range; contacts are gold flashed silver
    • Limit Contact Adjustment: by 1/16 in. hex wrench through 100% of scale
    • Limit Contact Wire Leads 25DP Series: 18 AWG (1.0 mm2) x 12 in. (305 mm)
    • Limit Contact Terminals: A25DP Series #6 screw terminals
  • Unit Weight: 25DP and A25DP Series: 11 oz. (0.29 kg)
  • Unit Dimensions: 4-3/4 x 4-3/4 x 2-3/4 in. (121 x 121 x 70 mm)

Dimensions 25DP


Dimensions A25DP


Internal Wiring

For more information about this product, you can download the related literature here:

Sales Bulletin (96014; revision date – 08/2022)

Installation Manual (00-02-0162)