Dwyer Series 4000 Capsuhelic Differential Pressure Gauges

The Capsuhelic® gage is designed to give fast, accurate indication of differential pressures. The gage may be used as a readout device when measuring flowing fluids, pressure drop across filters, liquid levels in storage tanks and many other applications involving pressure, vacuum or differential pressure.

Using the basic design of Dwyer's time-proven Magnehelic® gage, the Capsuhelic® contains a simple, frictionless movement that permits full scale readings as low as 0.5 inch water column. The pressure being measured is held within a capsule which is an integral part of the gage. This containment of the pressure permits the use of the gage on system pressures of up to 500 psig, even when differentials to be read are less than 0.1 inch w.c.

The diaphragm-actuated Capsuhelic® gage requires no filling liquid which might limit its outdoor applications. Zero and range adjustments are made from outside the gage, and there is no need to disassemble the gage in normal service. Dimensional Information

NOTE: DO NOT use with hydrogen gas. Toxic and/or explosive gas may form due to reaction with rare earth magnet.

Service: Aluminum Case: Air and compatible gases and oil based liquids. Brass Case: Air and compatible gases and water based liquids.
Wetted Materials: Consult factory.
Housing: Die cast aluminum with impregnated hard coating, standard. Optional forged brass housing is required for water or water based fluids.Special material diaphragms available, contact factory.
Accuracy: ±3% of full scale at 70°F (21.1°C). (±2% on 4000S models, ±4% on 4200, 4210, 4215, 4220, 4300, 4400, and 4500).
Pressure Limits: -20" Hg to 500 psig. (-0.677 bar to 34.4 bar).
Temperature Limits: 20 to 200°F (-6.67 to 93.3°C).
Size: 4" (101.6 mm) diameter dial face.
Mounting Orientation: Diaphragm in vertical position. Consult factory for other position orientations.
Process Connections: 1/4" female NPT high and low pressure taps, duplicated - one pair top for air and gas, and one pair bottom for liquids.
Weight: 3 lb, 3 oz (1.45 kg) aluminum case; 7 lb, 13 oz (3.54 kg) brass case.
Standard Accessories: Two 1/4" NPT plugs for duplicate pressure taps, four flush mounting adapters with screws and four surface mounting screws.

Capsuhelic® gages may be flush mounted in a panel or surface mounted. Hardware is included for either. For flush mounting, a 4-13/16" diameter cutout in panel is required. Where high shock or vibration are problems, order optional A-496 Heavy Duty flush mount bracket. Optional A-610 kit provides simple means of attaching gage to 1-1/4" to 2" horizontal or vertical pipe. Installation is same as Magnehelic® gage. All standard models are calibrated for vertical mounting. Gages with ranges above 5 in. w.c. can be factory calibrated for horizontal or inclined mounting on special order.

• Flush mounted in panel
• Back view shows flush mounting adaptors.
• Back view for surface mounting.

1. Bezel provides flange for flush mounting in panel.
2. O-ring seal for cover assures dust tight integrity of case.
3. Clear plastic front cover is highly resistant to breakage. Provides undistorted viewing of pointer and scale.
4. Precision scale, screen printed on aluminum, is accurate and easy to read.
5. Red tipped pointer of heat treated aluminum tubing is easy to see. It is rigidly mounted on helix shaft.
6. Pointer stops of molded rubber prevent pointer over-travel without damage.
7. Samarium cobalt magnet mounted at end of range spring rotates helix without mechanical linkages.
8. "Wishbone" assembly provides mounting for helix, helix bearings and pointer shaft.
9. Thin wall magnetic "window" is well braced and of minimum area for maximum pressure capability.
10. Jeweled bearings for helix are shock-resistant mounted. They provide virtually friction-free rotation for helix. Rotation is damped with high viscosity silicone fluid.
11. Helix is precision milled from an alloy of high magnetic permeability, mounted in jeweled bearings, and rotates to align with magnetic field of magnet and transmit pressure indication to pointer.
12. Zero adjustment screw is conveniently located in plastic cover, accessible without removing cover. "O" ring seal provides dust seal.
13. Range spring calibration is screw adjusted. Rate adjust and rate adjust lock are coaxial and are factory set and sealed.
14. Top low pressure connection (for Air or Gas) connects to chamber in back of diaphragm. High pressure air or gas port (cut away; not shown) connects with chamber in front of diaphragm through passageways in case.
15. Precision made case is offered in two materials. Standard is die cast aluminum coated inside for resistance to most oils and similar fluids. Optional forged brass case is recommended when using water or water based liquids. One case size for all pressure ranges -- can be either surface or flush mounted.
16. Silicone rubber diaphragm with integrally molded O-ring is sealed between the case and backplate. Diaphragm motion is restricted to prevent damage due to over-pressure.
17. Diaphragm support plate of stainless steel minimizes position or attitude sensitivity.
18. Calibrated range spring is a flat leaf of nickel plated spring steel. Small amplitude of motion assures consistency and long life. It reacts to pressure on diaphragm. Live length factory adjusted for calibration.
19. Range spring mounting plate provides mounting for rate adjust screw and for the calibration range spring and magnet assembly.
20. Bottom high pressure connection (for Liquids) connects to chamber in front of diaphragm. Low pressure liquid connection (not visible) connects with chamber in back of diaphragm through passageways in case.