SKP55.012U1 Siemens Controller

Overview

The Siemens SKP55.012U1 is a high-performance electro-hydraulic actuator designed for use with Siemens VG series gas valves. It serves as a multifunctional safety component, providing safety shut-off, constant pressure regulation, and air/gas ratio control in a single compact unit. By integrating these three functions, it reduces the need for additional gas train components, significantly lowering the overall size, weight, and complexity of industrial and commercial burner systems. The actuator features a slow-opening and fast-closing mechanism, ensuring rapid fail-safe operation during power interruptions.

Features

• Combined safety shut-off, pressure regulation, and air/gas differential pressure control
• Integrated Proof of Closure (POC) switch for valve position verification
• Adjustable SPDT auxiliary switch for secondary signaling between 40% and 100% stroke
• Visual position indicator window showing the entire stroke of the valve
• “Power on” indication light for immediate status monitoring
• Modular design allowing for 360 degree rotation for flexible installation and field wiring
• No mechanical wear or play, preventing drifting and ensuring long-term ratio maintenance
• Compensation for combustion chamber back pressure fluctuations without additional circuits

Specifications

• Operating Voltage: 110 to 120 VAC (+10% / -15%)
• Frequency: 50 to 60 Hz
• Power Consumption: 13.5 VA
• Maximum Stroke: 1 inch (26 mm)
• Closing Time: Less than 0.8 seconds
• Opening Time: Approximately 14 seconds for maximum stroke (varies by valve size)
• Enclosure Rating: NEMA 1, 2, 5, and 12 (NEMA 3, 3R, 4 with optional AGA66 gasket)
• Approvals: UL listed, FM approved, CSA certified, and IRI approvable
• Weight: 4.2 lbs (1.9 kg)

Applications

• Supervision of air/gas ratio for recuperative burners with preheated combustion air
• Burner systems with continuously variable air or gas nozzle openings
• Industrial and commercial boilers, ovens, and dryers
• Process heating applications requiring 1:1 air/gas ratio control
• Systems where air or gas pressure is not representative of actual flow
• Burners operating with negative combustion air pressure levels