The TZK Series is designed for machines/work cells where access to a hazardous work area must be controlled until safe conditions exist. Their solenoid-latching feature permits locking a machine guard until dangerous conditions, which may exist immediately after removal of power, have abated. Solenoid-latching may be controlled by a time delay, motion detector, position sensor or other suitable component. The unit's contact arrangement permits the prevention of a machine restart until the guard is closed and in the locked position. Each unit is supplied with a 1/2" NPT conduit adapter.