QPL25.050 Siemens Pressure Switch

Overview

The Siemens QPL25.050 is a compact, automatic reset pressure switch designed for the supervision of air or gas pressures in industrial and commercial burner applications. It functions by monitoring the pressure of neutral gaseous media and triggering an electrical circuit change if the pressure falls below or exceeds a pre-adjusted switching point. Engineered for reliability, this switch is a critical safety component for gas trains and is often used in conjunction with Siemens burner controls and gas valves to ensure safe combustion processes.

Features

• Automatic reset functionality for continuous operation
• Compact design with an ISO 1/4 inch threaded connection
• Adjustable switching point via a manual setting knob located under a secure cover
• Internal diaphragm ensures high switching accuracy with minimal deviation
• Durable construction suitable for gas families I, II, and III
• IP54 rated protection against dust and water splashes
• Integrated test point for easy pressure verification during maintenance

Specifications

• Working Pressure Range: 0.5 to 5.0 kPa (5 to 50 mBar)
• Maximum Operating Pressure: 60 to 69 kPa (continuously)
• Switching Differential: 0.3 kPa
• Switching Voltage: AC max. 250-280 V, DC 24-48 V
• Switching Current: AC max. 6 A (resistive), DC max. 1 A
• Operating Temperature: -15 C to +60 C
• Connection: 1/4 inch ISO thread
• Weight: Approximately 120 g to 143 g

Applications

• Supervision of gas or air pressures in gas trains of gas-fired equipment
• Minimum or maximum pressure monitoring for industrial gas burners
• Use in HVAC systems, commercial boilers, and process heating plants
• Integration into OEM burner control systems for safety shut-off functions
• Monitoring of neutral gaseous media in controlled industrial environments