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Murphy by Enovation AT Series Speed/Time Sensors

The AT Series tachometers are rugged, transistorized instruments with solid-state circuitry for indication of engine RPM. They are equipped with a bracket for mounting into a standard 3- 3/8 in. (86 mm) dash mounting hole. A full 270° sweep of the pointer gives an accurate indication on a large easy–to–read scale and the dial can be illuminated for night reading. The ATH Series models are also equipped with hourmeter to record the elapsed running time of an engine.

• 4000 RPM – 0 to 100,000 hours
• Sensing from Magnetic Sensor, Battery Charging Alternator or Ignition Signal
• High Visibility Analog Readout
• Air Core Movement
• Easy Calibration through Dip Switches
• Through Dial Lighting
• Powered by 11-28 VDC Battery Available

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Power Supply: Voltage: 8-30 VDC. Maximum Current: 150 mA.

Frequency Signal: (Voltage, Magnetic Pickup Signal Models):

  • Minimum: 0.35 Vrms.
  • Maximum: 60 Vrms.

Maximum Current, Magnetic Pickup Signal Models: 4.8 µA.
Adjustment Range, Magnetic Pickup Signal Models:

  • Crank Disconnect: 250-6,000 Hz.
  • Overspeed: 1,100-10,000 Hz.

Reset Differential, Magnetic Pickup Signal Models:

  • Crank Disconnect: Dropout 160 Hz ± 5%.
  • Overspeed: 200 Hz Differential.

Output: Relay Contact, SPDT, Resistive Load: (2) 5 A 30 VDC.

Adjustment: (2) 270°–turn potentiometer.

Temperature Range: 14 to 158°F (-10 to 70°C).

Shipping Weight: 2 lbs. (0.90 Kg).

Shipping Dimensions: 10 x 9 x 6 in. (254 x 229 x 152 mm).

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