The MZM 100 Series is designed for machine/work cells where access to a hazardous work area must be controlled until safe conditions exist. Their magnetic-latching feature permits locking a machine guard until dangerous conditions, which may exist immediately after removal of power, have abated. The MZM 100 consists of a magnetic-latching interlock and actuator unit. An electromagnet is utilized to generate a 500 N holding force. An integrated pulse-echo based sensor detects and monitors the position of the safety guard. This sensor technology permits an offset between the actuator and interlock of ±5 mm vertical and ±3 mm horizontal. The MZM100 magnetic-latching interlock is a dual channel design with two short-circuit proof, safe PNP outputs, each of which can switch up to 250 mA. The holding force is permanently electronically measured and monitored. If the holding force drops below 500 N, the safety outputs are not enabled, recognizing a dirty interlock. With continuous internal function tests, the monitoring of the safety outputs and the use of door detection sensors, MZM 100 magnetic-latching interlocks can be wired in series without detriment to the control category. Series wired MZM 100s continue to fulfill the requirements of Control Category 4 according to EN 954-1 (without the need of a second switch).