Switchmaster Limit Switch Box — Valve Position Indicator for Quarter-Turn Actuators in IP67
The Switchmaster limit switch box is a compact valve position monitor for quarter-turn actuators on butterfly valves, ball valves and other quarter-turn applications. Three variants cover all common requirements: the M2 with mechanical gold-plated contacts, the D2 with inductive PNP sensors and the N2 as ATEX-rated Namur version. All variants are rated IP67 and operate in a temperature range of –20 °C to +70 °C. The antistatic Lexan 143 housing is impact-resistant and suitable for continuous industrial service. The 0–90° swing angle provides reliable valve position indication on ball valves and butterfly valves with quarter-turn actuators. FERGO supplies the actuator switch box ex stock — pre-mounted on the actuator on request.
Variants and Technical Data: M2, D2 and N2
The limit switch box M2 uses mechanical microswitches with gold-plated changeover contacts for reliable valve position feedback. The switching range is 4 V DC to 250 V AC at a switching current of 1 mA to 5 A. The D2 variant uses contactless inductive PNP sensors (10–30 V DC, 100 mA) for wear-free operation. The limit switch box ATEX Namur type N2 is designed to EN 60947-5-6 as a Namur sensor — ignition protection type Ex ia IIB T6 to ATEX 2014/34/EU, 8 V DC supply at a maximum of 34 mW. All three variants include a visual position indicator on the housing.
Housing, Protection and Mounting
The Switchmaster limit switch box housing is manufactured from Lexan 143 with antistatic coating — impact-resistant, UV-stable and designed for continuous industrial use. The limit switch box IP67 rating protects the electronics reliably against dust and temporary submersion. The adjustable 0–90° swing angle allows precise alignment of the switching points with the valve end positions. Direct mounting on pneumatic and electric quarter-turn actuators is via standardised mounting flanges to VDI/VDE 3845 and DIN ISO 5211. The integrated visual position indicator shows the valve position (open/closed) directly at the actuator.
Accessories and Ordering
The Switchmaster limit switch box can be combined with solenoid valves, positioners and stem extensions — for a complete automation solution on the quarter-turn actuator. Mounting on butterfly valves, ball valves and quarter-turn fittings is carried out in-house by FERGO. For custom solutions, project quantities or selecting the right valve position indicator, the FERGO team is available.
