The TD, TR and TS are solid state time delay units for use where machines do not come to an immediate stop.  The gate access key is held captive in the unit until the desired condition of the machine or process has been achieved.The time delay (TD) is initiated by the insertion of a key that would normally be released from the operation of an isolator.  Therefore the time delay cannot start until the machine power has been shut off.  There is a facility to add an additional switch to a TD to prevent accidental start-up.The TD, TR and TS units uses a timer relay that provides a delay on energisation in accordance with VDE 0113-1, 11/98, EN 60204-1, EN 1088, 12/97 and IEC 204-1, 11/98