The Ruelco SS-1 Model 4102 pneumatic pressure switch is a three way block and bleed valve that is operated by pressure acting on a piston opposing an adjustable spring force. It functions as either a normally closed or normally open valve, depending on through which of the two ports the instrument pressure is supplied. The output port is the same for either mode of operation. Pressure applied to the sense port will cause the valve to operate.

• 316 stainless steel construction (models to N.A.C.E. MR0175 available).
• Standard base range 10-10,000 PSI (with 1/4″ piston option).
• Operating pressure range from .5 to 20,000 PSI.
• Block and bleed 3-way valve.
• Holds constant and accurate set points.
• Designed for 1% plus or minus repeatability on set points.
• Minimum deadband between trip and reset pressure.
• Spring may be replaced with instrument and sensing pressure present in the sensor.
• Vent above sensing piston prevents high pressure from entering instrument supply should a piston seal leak develop.
• Optional indicating scale available (Model 4103).
• SIL 3 Certified models available.

Safety Integrity Level