Product Overview

The 017-520366 (017-520366) is a heavy-duty industrial pressure switch from the renowned Danfoss RT series, specifically engineered for general-purpose pressure control and safety monitoring. Rated for a regulating range of 1 to 10 bar, this switch provides reliable mechanical logic for starting and stopping pumps, compressors, or triggering alarms in industrial heating, ventilation, and steam plant systems. The 017-520366 features a robust SPDT (Single Pole Double Throw) contact system with automatic reset, housed in a high-durability enclosure. Its 22 bar maximum working pressure rating ensures high operational safety margins, making it a staple component in demanding boiler room and marine mechanical environments where long-term repeatability is critical.

Technical Configuration

The 017-520366 utilizes a balanced mechanical design for industrial reliability:

• RT Series Engineering: Recognized for its high degree of enclosure protection and vibration resistance, the RT series is the industrial standard for critical regulation.

• Adjustable Differential: Features a differential range of 0.33 to 1.3 bar, allowing engineers to fine-tune the "deadband" between the cut-in and cut-out points to prevent equipment short-cycling.

• SPDT Contact System: The Single Pole Double Throw (SPDT) configuration allows the switch to be used for both "high-limit" (opening the circuit on rising pressure) and "low-limit" (opening on falling pressure) functions simultaneously.

• Automatic Reset: The unit automatically returns to its operating state once the pressure moves back across the differential threshold, ensuring continuous process operation without manual intervention.

Technical Specifications

Technical FAQs

Can the 017-520366 be used for steam applications?

Yes. The RT series pressure switches are frequently used in steam boiler systems. However, to protect the internal bellows from high-temperature steam, it is mandatory to use a water-filled pigtail syphon between the steam line and the 3/8 BSP connection.

How do I adjust the pressure setpoint and differential?

The main range is set using the range spindle on top of the switch (visible through the window). The differential is adjusted using the internal differential setting nut. Turning the spindle clockwise increases the setpoint pressure.

What is the electrical rating of the SPDT contacts?

RT series switches typically feature heavy-duty contacts capable of handling inductive loads. While generally rated for up to 10A at 400V AC, always verify the specific AC-1 (resistive) and AC-15 (inductive) ratings on the product nameplate before wiring directly to a motor.

Engineering & Installation Guide

• Mounting for Vibration: While the RT series is highly resistant to vibration, mounting the switch on a wall or a vibration-damped bracket is recommended if the primary piping is subject to heavy mechanical stress.

• Sealing the Enclosure: To maintain the high IP rating (typically IP66 for RT series), ensure the cable entry is sealed with a properly sized cable gland and that the front cover screws are tightened. Moisture ingress is the leading cause of electrical contact pitting.

• Differential Optimization: For pump control, a narrow differential (0.33 bar) provides precise pressure maintenance but increases the frequency of motor starts. A wider differential (1.3 bar) reduces wear on the motor starter but results in larger pressure fluctuations in the system.