Dwyer A3002 Photohelic Pressure Switch Gauge Range 0-2.0 Inch w.c.

Product Description

Dwyer A3002 Photohelic Pressure Switch Gauge Range 0-2.0 Inch w.c.

Dwyer A3002 Photohelic Pressure Switch/Gauge (0-2.0"w.c.)

Model: A3002

Bezel and front cover (with set point knobs and zero adjustment screw) removed to expose Photohelic switch/gage set point mechanism. Cover is clear polycarbonate plastic. Gage pointer and light shutter are mounted on helix and balancing counter Weight.

MORE ABOUT THIS ITEM

The Photohelic Switch/Gauge functions as versatile, highly repeatable pressure switches combined with a precise pressure gauge employing the time-proven Magnehelic gauge design. The Photohelic switch/gauge 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 setpoint indicators are controlled by knobs located on the gauge face. Individual setpoint deadband is one pointer width - less than 1% of full scale. Setpoints can be interlocked to provide variable deadband - ideal for control of fans, dampers, etc. Gauge reading is continuous and unaffected by switch operation, even during loss of electrical power. In typical applications, these switch/gauges control between high and low pressure set points. When pressure changes, reaching either set point pressure, the infrared light to the limiting phototransistor is cut off by the helix-driven light shutter. The resulting phototransistor signal is electronically amplified to actuate its DPDT slave relay and switching occurs. Dead band between make and break is 1% of full scale or less - just enough to assure positive, chatter-free operation. A plastic housing protects all electronic components. Solid-state and integrated circuit electronics are on glass-epoxy printed circuit boards and self-extinguishing terminal boards.<br><br>

Photohelic switch/gauges are used to control pressures in air conditioning systems, clean rooms, fluidic and pneumatic control systems, materials handling equipment, alarm or control fume exhaust systems, control pressure in air structures, and monitor respiratory and blood pressures.

Warning: This product is not approved or intended for, and should not be used for medical, clinical, surgical or other patient oriented applications.

Dwyer A3002 Specifications

Switch Specifications

• Switch Type:Each set point has 2 Form C relays (DPDT)
• Repeatability:1% of FS
• Electrical Rating:10 A at 28 VDC,10 A at 120,240 VAC
• Electrical Connections:Screw terminals. Use 167F (75C) copper conductors only
• Power Requirements:120 VAC, 50/60 Hz,240 VAC and 24 VAC power optional
• Mounting Orientation:Diaphragm in vertical position. Consult factory for other position orientations
• Set Point Adjustment:Adjustable knobs on face
• Agency Approvals:CE, CSA, UL

Gauge Specifications

• Service:Air and non-combustible, compatible gases
• Accuracy:2% of FS at 70F (21.1C),3% on -0,4% on -00 models
• Pressure Limits:-20" Hg to 25 psig (-0.677 to 1.72 bar),MP option; 35 psig (2.41 bar),HP option; 80 psig (5.52 bar)
• Temperature Limits:20 to 120F. (-6.67 to 48.9C),-20 to 120F (-28 to 48.9C) with low temperature option
• Process Connections: female NPT
• Dimensions:4" (101.6 mm) dial face,5 x 8" (127 x 209.55 mm)
• Weight:4 lb (1.81 kg)