PR- 4 Manual Reset Relay
(Model 1902)

The Ruelco PR-4 relay is a multi-pressure control valve for production control and safety systems. It functions as a pilot operated, normally closed, block and bleed valve. Its simple and compact design makes maintenance and repair easy. The PR-4 relay does not need to be removed from its control panel or system loop if repair or maintenance is necessary.

• 316 stainless steel construction (models to N.A.C.E. MR0175 available).
• Easy to close with pilot signal pressures as high as 100 PSI.
• Can be repaired without removing relay from system or panel.
• May be used in pneumatic or hydraulic systems.
• ‘Lock closed’ design prevents relay from automatically opening.
• Viton and nitrile seals are utilized for dependability.
• Design minimizes malfunctions due to supply system debris.
• Inconel X-750 20 PSI spring assures dependability in most corrosive environments (optional 30 PSI spring available).
• Optional stem protector available to prevent external debris accumulation on relay shaft.
• Available with black, red, or green knob (green standard).