QPL31.280A00 Siemens Pressure Switch

Overview

The Siemens QPL31.280A00 is a high-performance automatic reset low-pressure switch from the QP series, specifically engineered for the supervision of gas or air pressures in industrial and commercial burner applications. As a safety-critical component, it is designed to break the electrical circuit when the monitored pressure drops below a pre-adjusted setpoint, preventing potentially hazardous conditions. This switch is known for its robust construction, ventless installation capability, and high surge tolerance, ensuring reliable operation within complex combustion and HVAC systems.

Features

• Automatic reset functionality ensures the system resumes operation once pressure returns to safe levels
• Adjustable pressure range allows for precise setting between 28 and 112 inches water column
• Integrated surge protection handles pressure spikes up to 15 psi for 2 seconds
• Internal range dial facilitates easy adjustments by removing the protective cover
• Ventless installation design eliminates the need for external vent piping in many applications
• Durable metal base with a standard 1/4-inch NPT female pressure connection
• Certified for safety and reliability with UL listing, FM approval, and ISO 9001 certification

Specifications

• Model: QPL31.280A00
• Pressure Range: 28 to 112 inches W.C. (70 to 280 mbar)
• Reset Type: Automatic
• Electrical Rating: 10A @ 125 to 250 Vac; 1/3 HP @ 125 to 250 Vac
• Maximum Operating Pressure: 6 psi (400 mbar)
• Maximum Surge Pressure: 15 psi (1 bar)
• Operating Temperature Range: -40 F to 140 F (-40 C to 60 C)
• Mounting Position: Horizontal or vertical
• Connection: 1/4-inch NPT (Female)

Applications

• Supervision of air or gas pressures in gas trains for gas-fired equipment and industrial burners
• Low-pressure monitoring in commercial HVAC and boiler systems to ensure safe airflow and fuel supply
• Protection of combustion systems by interrupting electrical circuits upon a drop in pressure
• Integration into burner control systems for OEMs and industrial facilities requiring FM and UL approved safety switches