Fisher 377 Pneumatic Trip Valve for Emergency Shutdown Systems

The Fisher 377 Trip Valve is a pressure-sensing pneumatic device designed to automatically shut off or trip an actuator when a predefined pressure level is reached. Engineered by Emerson, the 377 is widely used in emergency shutdown (ESD) applications to ensure rapid, reliable response to abnormal pressure conditions.

This compact, field-proven trip valve is essential in critical process safety systems where fast pressure-based actuation is required, helping safeguard equipment, personnel, and the environment.

• Automatically trips actuator based on sensed pressure
• Compatible with spring-return and double-acting actuators
• Manual or automatic reset options
• Field-adjustable trip pressure
• Pneumatic design with no electrical power required
• Compact size, corrosion-resistant materials
• Designed for high-reliability performance in harsh industrial environments
• Ideal for integration with Fisher control valves and actuator systems

• Emergency Shutdown Systems (ESD)
• Compressor Surge Protection
• Pressure Trip Systems (High/Low)
• Fail-safe valve systems in oil and gas
• Venting systems for chemical plants
• Boiler protection and turbine control