Description
APL210 Valve Limit Switch Box – NAMUR Pneumatic Actuators
The APL210 Valve Limit Switch Box provides reliable open and closed valve position feedback for pneumatically actuated ball valves, butterfly valves and other quarter-turn valve assemblies.
Designed for direct installation onto NAMUR pneumatic actuators, the APL210 uses two mechanical micro switches to provide independent electrical confirmation of the valve's fully open and fully closed positions.
Suitable for both spring return and double acting pneumatic actuators, the compact switch box provides a simple and robust method of transmitting valve position status to PLCs, control panels, relays and industrial automation systems.
Valve Position Feedback
The APL210 is designed to provide positive electrical indication of the position of a pneumatically actuated valve.
Two internal mechanical micro switches are operated by adjustable cams connected to the actuator shaft. One switch can be configured to indicate the fully open position, while the second confirms the fully closed position.
This provides straightforward valve status feedback for:
✓ PLC inputs
✓ Control panels
✓ Remote valve indication
✓ Process interlocking
✓ Automated machinery
✓ Valve monitoring systems
NAMUR Pneumatic Actuator Mounting
The switch box is designed for use with NAMUR-style quarter-turn pneumatic actuators and is suitable for actuator sizes from 52mm to 125mm.
A 17mm stainless steel NAMUR drive shaft transfers actuator rotation to the internal position cams.
The supplied stainless steel mounting bracket and fasteners provide a robust connection between the actuator and switch box.
Adjustable Open & Closed Positions
The APL210 operates through a 90° quarter-turn rotation, making it suitable for common pneumatic ball valve and butterfly valve assemblies.
Spring-loaded cams allow the two switching points to be adjusted independently during commissioning, enabling accurate indication of the required open and closed valve positions.
Electrical Specifications
Switch type: Dual mechanical micro switches
Terminal connections: 8-way terminal strip
Cable capacity: 0.08–2.5mm²
Electrical ratings:
✓ 250VAC – 0.2A
✓ 125VDC – 0.4A
✓ 30VDC – 4A
Cable entries: 2 × M20 × 1.5
The terminal arrangement allows convenient connection to PLCs, control panels, relays and other compatible valve-monitoring circuits.
Mechanical Specifications
Operation: 90° rotary position feedback
Cam adjustment: Spring-loaded adjustable cams
NAMUR shaft: 17mm stainless steel
Mounting bracket: Stainless steel
Fasteners: Stainless steel
Actuator compatibility: 52mm to 125mm pneumatic actuators
Operating Conditions
Operating temperature: -20°C to +80°C
The robust construction makes the APL210 suitable for general industrial automation and pneumatically actuated valve installations within its specified environmental and electrical ratings.
Typical Applications
The APL210 valve limit switch box is suitable for:
✓ Pneumatic ball valves
✓ Pneumatic butterfly valves
✓ Spring return actuators
✓ Double acting actuators
✓ Valve open/closed indication
✓ PLC valve status feedback
✓ Process control systems
✓ Automated production machinery
✓ Water treatment equipment
✓ Industrial valve automation
Why Use a Valve Limit Switch Box?
A pneumatic actuator can mechanically open or close a valve, but the control system does not necessarily know whether the valve has actually reached the commanded position.
The APL210 provides independent electrical position feedback, allowing the control system to confirm that the actuator and valve have reached their open or closed positions.
This is particularly useful where valve status is required for process sequencing, alarms, interlocks or remote monitoring.
Related Products & Categories
Pneumatic Actuators
Air Actuated Ball & Butterfly Valves
Motor Actuated Valves
