Advanced Specialty Gas Equipment

Models SG6540, SG6541
General Service & Explosion Proof Pressure Switches

General Serice Pressure SwitchPressure switches monitor line pressure and can activate an external alarm (not supplied) when a certain predetermined pressure is reached. They can be set to activate on either increasing or decreasing pressure.

Pressure switches are commonly used with cylinder manifolds to warn against product depletion. For example, a switch set to activate on decreasing pressure can alert the user that manifold pressure is low and that a cylinder changeout is required.

Two models of pressure switches are available; a general service version for nonflammable gases, and an explosion-proof version for flammable gases or Oxygen. The explosion-proof model is UL listed and CSA certified for use in hazardous locations Class I Groups A, B, C, D and Class II Groups E, F, G. Each model has a single-pole, double throw, electrical switch with a maximum rating of 15 amps at 250 VAC. Their weather tight housings are constructed of aluminum.

Pressure switches are supplied with two compression-type male connectors and five feet of stainless steel tubing for connection to a manifold or pipeline.

Maximum Inlet Pressure

Operating Temp. Range: -30°F to 200°F
   (+32°F to 400°F with Viton® seals)

Adjustable Pressure Range

Electrical Rating:
  15 amps at 250 VAC
   5 amps at 30 VDC (resistive)

Minimum Current Required: 100mA

Housing: NEMA 4, 4X, IP65

Pressure Port Connection: 1/4" NPT female

Male Connectors (2 supplied):
  1/4" NPT male by 1/8" compression and
  1/8" NPT male by 1/8" compression

Tubing: 5' x 1/8" OD

Approximate Weight:
   SG6540: 2 lbs
   SG6541: 3 lbs

Materials of Construction
Housing: Aluminum
Diaphragm: Type 316 Stainless Steel
Pressure Port: Type 316 Stainless Steel
Male Connectors: Type 316 Stainless Steel
Tubing: Type 316 Stainless Steel

Internal view of pressure switch

Application Note Oxygen Service: We strongly recommend the use of our Explosion-Proof Type Pressure Switch for Oxygen Applications. The Explosion-Proof models contain a hermetically sealed switching element, which provides a safe environment for handling Pure Oxygen.


Table I, General Service and Explosion-Proof Pressure Switches
General Service
Part No.
Explosion-Proof Service
Part No
Inlet Pressure
Seal Material
SG6540-2-N-(psig) SG6541-2-N-(psig) 3000 psig 12–100 psig Neoprene
SG6540-2-V-(psig) SG6541-2-V-(psig) 3000 psig 12–100 psig Viton®
SG6540-3-N-(psig) SG6541-3-N-(psig) 3000 psig 45–550 psig Neoprene
SG6540-3-V-(psig) SG6541-3-V-(psig) 3000 psig 45–550 psig Viton®
SG6540-4-N-(psig) SG6541-4-N-(psig) 5000 psig 500–4000 psig Neoprene
SG6540-4-V-(psig) SG6541-4-V-(psig) 5000 psig 500–4000 psig Viton®
Where "(psig)" is indicated above, insert desired pressure setting. Example: SG6540-2-N-20. Switch will be factory set to activate at 20 psig.
Note: Models SG6540-4 and SG6541-4 can be factory set to activate up to 2000 psig. Settings for pressures above 2000 must be field set.
** Other ranges available on special order.