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Dwyer A3000-150Mm-240Vac, A3000 Photohelic Switch/Gage

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USD 348.20

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Dwyer, A3000-150MM-240VAC, A3000 Photohelic 240 VAC Pressure Switch/Gage, Range 0-150 mm w.c



3-in-1 Indicating Gage, Lo-limit and Hi-limit Control Photohelic 174 Switch/Gages function as versatile, highly repeatable pressure switches combined with a precise pressure gage employing the time-proven Magnehelic 174 gage design

Approvals CSA Certified - Industrial Control Equipment CSA Certified - Switches UL Approval - US CE GOST-R Certificate

Attached directly to set pointers, they are individually aligned to assure precise switching accuracy

Dead band between make and break is 1 of full scale or less - just enough to assure positive, chatter-free operation

Easy to adjust set point indicators are controlled by knobs located on the gage face

Electronics are designed to operate on 50 Hz, 240 Volt current with 10 over or under voltage

Gage pointer and light shutter are mounted on helix and balancing counterweight

Gage reading is continuous and unaffected by switch operation, even during loss of electrical power

Glass epoxy printed circuit boards for durability and permanence

Individual set point deadband is one pointer width - less than 1 of full scale

It also gives interior a clean finished look

Light shield effectively protects phototransistors from strong outside light sources yet allows free pointer movement

Load relays are DPDT with latching feature for maximum application versatility

Optical limit switches are used for reliability and long service life

Photohelic Sensing - How It Works In typical applications, these Dwyer switch/gages control between high and low pressure set points

Plastic enclosure protects electronic components and electrical connections

Polycarbonate connection or terminal board is self-extinguishing

Product Applications Air Conditioner Systems Clean Rooms Fume Exhaust Systems Features Bezel and front cover with set point knobs and zero adjustment screw removed to expose Photohelic 174 switch/gage set point mechanism.Cover is clear polycarbonate plastic

Relay-Transformer Features A plastic housing protects all electronic components

Semi-Flexible drive shaft connects to set point knobs

Set points can be interlocked to provide variable deadband - ideal for control of fans, dampers, etc

Shutter passes through slot in optical limit switch to expose phototransistors to integral infrared light source or mask them depending on applied pressure

Solid-state and integrated circuit electronics are on glass-epoxy printed circuit boards and self-extinguishing terminal boards

Spring loaded friction clutch prevents operator damage of set point mechanism

Switch set pointers show switch settings at all times

The Photohelic 174 switch/gage measures and controls positive, negative or differential pressures of air and compatible gases

The resulting phototransistor signal is electronically amplified to actuate its DPDT slave relay and switching occurs

Two phototransistor actuated, DPDT relays are included for low/high limit control

When pressure changes, reaching either set point pressure, the infrared light to the limiting phototransistor is cut off by the helix-driven light shutter

Zero adjustment screw connects to screw in cover to adjust zero pressure reading


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