QPL31.050A00 Siemens Pressure Switch

Overview

The Siemens QPL31.050A00 is an automatic reset low-pressure switch designed to monitor gas or air pressures in industrial and commercial burner applications. As a safety-critical component, it is engineered to break the electrical circuit when the pressure falls below the user-adjusted setpoint. This switch is suitable for use with gas families 1, 2, and 3, as well as other neutral gaseous media, ensuring reliable supervision of gas trains and air-fired equipment.

Features

• Automatic reset mechanism that restores the circuit once pressure rises above the setpoint
• Adjustable pressure range specifically calibrated for low-pressure monitoring
• Ventless installation design allows for flexible mounting without external vent piping
• Surge protection capable of withstanding up to 15 psi for short durations
• Integrated SPDT (Single Pole Double Throw) switch for versatile electrical integration
• Durable construction suitable for both horizontal and vertical mounting positions

Specifications

• Pressure Range: 1 to 20 inches water column (wc) / 2.5 to 50 mbar
• Reset Type: Automatic
• Maximum Operating Pressure: 6 psi (400 mbar)
• Maximum Surge Pressure: 15 psi (1 bar) for 2 seconds
• Operating Temperature: -40 F to 140 F (-40 C to 60 C)
• Electrical Rating: 10A @ 125 to 250 Vac; 1/3 HP @ 125 to 250 Vac
• Pressure Connection: 1/4-inch NPT female
• Approvals: UL Listed, FM Approved, ISO 9001 Certified

Applications

• Supervision of air or gas pressures in gas trains of gas-fired equipment
• Low-pressure limit monitoring for industrial and commercial burners
• Safety shut-off integration in HVAC and boiler systems
• Monitoring of neutral gaseous media in burner control cycles