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Dwyer Instruments A3000 series Photohelic® dual switch and gauge function as versatile, highly repeatable pressure switches combined with a precise pressure gauge. The A3000 measures and controls positive, negative or differential pressures of air and compatible gases. Two phototransistor actuated, DPDT relays are included for low/high limit control. Easy to adjust set point indicators controlled by knobs on the gauge face. Gauge reading is continuous and unaffected by switch operation, even during loss of electrical power.
In typical applications, these switch/gauges controls between high and low-pressure set points. When pressure changes, reaching the set point pressure, the infrared light to the limiting phototransistor is cut off. The resulting phototransistor signal is electronically amplified to actuate its DPDT slave relay and switching occurs.
Minimum Operating Pressure = 0psi
Maximum Operating Pressure = 0.01 psi
Pressure Type = Differential
Suitable Media = Air, Gas, Non Combustible
Connection = NPT 1/8 in Female
Type = Pressure Switch/Gauge
Voltage Rating = 120V ac
Connection Thread Size = 1/8 in
Manufacturer Series = A3000
Contact Operation = DPDT