Select the Magnehelic gage for high accuracy--guaranteed within 2% of full scale--and for the wide choice of 81 models available to suit your needs precisely. Using Dwyer's simple, frictionless Magnehelic gage movement, it quickly indicates low air or non-corrosive gas pressures--either positive, negative (vacuum) or differential. The design resists shock, vibration and over-pressures. No manometer fluid to evaporate, freeze or cause toxic or leveling problems. It's inexpensive, too. The Magnehelic gage is the industry standard to measure fan and blower pressures, filter resistance, air velocity, furnace draft, pressure drop across orifice plates, liquid levels with bubbler systems and pressures in fluid amplifier or fluidic systems. It also checks gas-air ratio controls and automatic valves, and monitors blood and respiratory pressures in medical care equipment.Note: May be used with Hydrogen. Order a Buna-N diaphragm. Pressures must be less than 35 psi.
Bezel provides flange for flush mounting in panel
Clear plastic face is highly resistant to breakage. Provides undistorted viewing of pointer and scale
Precision litho-printed scale is accurate and easy to read
Red tipped pointer of heat treated aluminum tubing is easy to see. It is rigidly mounted on the helix shaft
Pointer stops of molded rubber prevent pointer over-travel without damage
"Wishbone" assembly provides mounting for helix, helix bearings and pointer shaft
Jeweled bearings are shock-resistant mounted
provide virtually friction-free motion for helix. Motion damped with high viscosity silicone fluid
Zero adjustment screw is conveniently located in the plastic cover, and is accessible without removing the cover. O-ring seal provides pressure tightness
Helix is precision made from an alloy of high magnetic permeability. Mounted in jeweled bearings, it turns freely, following the magnetic field to move the pointer across the scale
Samarium Cobalt magnet mounted at one end of range spring rotates helix without mechanical linkages. Calibrated range spring is flat spring steel. Small amplitude of motion assures consistency and long life. It reacts to pressure on diaphragm. Live length adjustable for calibration
Silicone rubber diaphragm with integrally molded O-ring is supported by front and rear plates. It is locked and sealed in position with a sealing plate and retaining ring. Diaphragm motion is restricted to prevent damage due to overpressures
Die cast aluminum case is precision made and iridite-dipped to withstand 168 hour salt spray corrosion test. Exterior finished in baked dark gray hammerloid. One case size is used for all standard pressure options, and for both surface and flush mounting
Blowout plug of silicone rubber protects against overpressure on 15 psig rated models. Opens at approximately 25 psig
O-ring seal for cover assures pressure integrity of case.