Dwyer A3000-1.5KPA Photohelic Pressure Switch/Gauge (0-1.5 kPa)
Bezel and Front Cover (with set point knobs and zero adjustment screw) removed to expose Photohelic switch/gage set point mechanism. Gage pointer and light shutter are mounted on helix and balancing counterweight.
Dwyer A3000-1.5KPA Series A3000 Photohelic Pressure Switch Range 0 to 1 5 kPa
The Dwyer A3000-1.5KPA has a Range From 0-1.5 kPA.
Photohelic Switch/Gauges Function as versatile,highly repeatable Pressure Switches combined with a precise pressure gauge employing the time-proven Magnehelic gauge design. The Photohelic switch/gage measures and controls positive, negative or differential pressures of air and compatible gases. Standard models are rated to 25 psig (1.7 bar) with options to 35 (2.4) or 80 (5.5 bar) psig. Single pressure 36000 S models measure to 6000 psig (413 bar) with a 9000 psig (620 bar) rating. Two phototransistor actuated, DPDT relays are included for low/high limit control. Easy to adjust set point indicators are controlled by knobs located on the gauge face. Individual set point deadband is one pointer width - less than 1% of full scale. Set points 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. Choose from full scale pressure ranges from a low 0-.25" (0-6 mm) w.c. up to 30 psi (21 bar); single positive pressure to 6000 psig (413 bar).
Photohelic Sensing - How It Works
In typical applications,these Dwyer Switch/Gages 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.
Service:Air and non-combustible,compatible gases.
Wetted Materials:Consult Factory.
Accuracy:2% of FS at 70F (21.1C). 3% on -0 and 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:1/8" female NPT.
Size:4" (101.6 mm) dial face,5" (127 mm) O.D. x 8-1/4"(209.55 mm).
Weight:4 lb (1.81 kg).
Switch Type:Each setpoint has 2 Form C relays (DPDT).
Repeatability:1% of FS.
Electrical Rating:10 A @ 28 VDC,10 A @ 120,240 VAC.
Electrical Connections:Screw terminals.Use 167F (75C) copper conductors only.
Power Requirements:120 VAC,50/60 Hz;240 VAC & 24 VAC power optional.
Mounting Orientation:Diaphragm in vertical position. Consult factory for other position orientations.
Set Point Adjustment:Adjustable knobs on face.