The D40A-2D5 is a non-contact safety interlock switch using Hall Effect technology — no mechanical wear at the actuation point, which is the main reason it lasts longer than a plunger-style switch on a frequently cycled guard door. Rated for 24 VDC with a 50 mA photocoupler output, it is designed for safety circuits where you need a solid-state signal to a safety PLC or relay, not a dry contact. The IP66/IP67 enclosure means it handles washdown environments — food processing, packaging lines, anywhere you hose down the guards. The switch is low level coded per EN ISO 14119, which means the actuator and sensor are a matched pair — you cannot defeat it by swapping in a generic magnet. The safety contact operating distances are On at 5 mm and Off at 15 mm, so the guard has to be within 5 mm to let the machine run, and it drops the safety signal once the gap exceeds 15 mm. That 10 mm hysteresis gives you some tolerance for door sag or vibration without nuisance trips.
Integration details
The switch body measures 48.0 x 25.0 mm, the actuator 48.0 x 17.0 mm — both fit a standard 48 mm wide guard profile. Connection is via a 5 m pigtail cable (molded PBT case, PVC jacket), so you can run it straight to the control cabinet or a junction box without an extra connector. The built-in LED (Yes) gives a quick visual on actuation status — handy when you are troubleshooting a guard interlock from outside the panel. The Hall Effect technology is inherently immune to dust and light contamination, unlike optical sensors, so it is a solid choice for dirty or steamy guard doors.