Magnehelic® Differential Pressure Gages Series 2000
Indicate positive, negative, or differential. Accurate within 2%

Select the Dwyer Magnehelic gage for high accuracy - guaranteed within 2% of full scale - and for the wide choice of 81 ranges available to suit your needs precisely. Using Dwyer's simple, frictionless Magnehelic 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.

Widely used 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.

MOUNTING. A single case size is used for most ranges of Magnehelic gages. They can be flush or surface mounted with standard hardware supplied. With the optional A-610 Pipe Mounting Kit they may be conveniently installed on horizontal or vertical 1¼" - 2" pipe. Although calibrated for vertical position, many ranges above 1 inch may be used at any angle by simply re-zeroing. However, for maximum accuracy, they must be calibrated in the same position in which they are used. These characteristics make Magnehelic gages ideal for both stationary and portable applications. A 4 9/16" hole is required for flush panel mounting. Complete mounting and connection fittings plus instructions are furnished with each instrument.

Vent valves
In applications where pressure is continuous and the Magnehelic gage is connected by metal or plastic tubing which cannot be easily removed, we suggest using Dwyer A-310A vent valves to connect gage. Pressure can then be removed to check or re-zero the gage.

High and medium pressure models
Installation is similar to standard gages except that a 4 13/l6" hole is needed for flush mounting. The medium pressure construction is rated for internal pressures up to 35 psig and the high pressure up to 80 psig. Available in all ranges. Because of larger case, will not fit in portable case. Weight 1 lb., 10 oz. (Installation of the A-321 safety relief valve on standard Magnehelic gages often provides adequate protection against infrequent overpressure; see Bulletin S-101).

OPTIONS AND ACCESSORIES
Transparent overlays
Furnished in red and green to highlight and emphasize critical pressures.

Adjustable signal flag
Integral with plastic gage cover; has external reset screw. Available for most ranges except those with medium or high pressure construction. Can be ordered with gage or separately.

LED Setpoint Indicator
Bright red LED on right of scale shows when setpoint is reached. Field adjustable from gage face, unit operates on 12 - 24 VDC Requires MP or HP style cover and bezel.

Portable units
Combine carrying case with any Magnehelic gage of standard range (not high pressure) includes 9 ft. (2.7 m) of 3/16" I.D. rubber tubing, stand-hang bracket, and terminal tube with holder.

Air filter gage accessory package
Adapts any standard Magnehelic for use as an air filter gage. Includes aluminum surface mounting bracket with screws, two 5 ft. (1.5 m) lengths of ¼" aluminum tubing, two static pressure tips and two molded plastic vent valves, integral compression fittings on both tips and valves.

1. Bezel provides flange for flush mounting in panel.
2. Clear plastic face is highly resistant to breakage. Provides undistorted viewing of pointer and scale.
3. Precision litho-printed scale is accurate and easy to read.
4. Red tipped pointer of heat treated aluminum tubing is easy to see. It is rigidly mounted on helix shaft.
5. Pointer stops of molded rubber prevent pointer over-travel without damage.
6. "Wishbone" assembly provides mounting for helix, helix bearings and pointer shaft.
7. Jeweled bearings are shock-resistant mounted; provide virtually friction-free motion for helix. Motion damped with high viscosity silicone fluid.
8. Zero adjustment screw is conveniently located in plastic cover, accessible without removing cover. O-ring seal provides pressure tightness.
9. Helix is precision milled from an alloy of high magnetic permeability. Mounted in jeweled bearings, it turns freely to align with magnetic field of magnet to transmit pressure indication.
10. Samarium Cobalt magnet mounted at one end of range spring rotates helix without mechanical linkages.
11. Calibrated range spring is flat spring steel in temperature compensated design. Small amplitude of motion assures consistency and long life. It reacts to pressure on diaphragm. Live length adjustable for calibration.
12. 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.
13. Die cast aluminum case is precision made. Iridite-dipped to withstand 168 hour salt spray test. Exterior finished in baked dark gray hammerloid. One case size used for all standard pressure ranges, and for both surface and flush mounting.
14. Blowout plug of silicone rubber protects against overpressure on 15 PSIG rated models. Opens at approximately 25 PSIG.
15. "O" ring seal for cover assures pressure integrity of case.

SERIES 2000 MAGNEHELIC^® - MODELS AND RANGES
The models listed below will fulfill most requirements. Custom models can be provided for OEM customers. For special units with scales reading in ounces per square inch, inches of mercury, other metric units, etc., contact the factory.