Contactors and relays from certain manufacturers are constructed to work with a separately top-mounted ‘shock absorber’ mechanism. It is attached as an accessory to the basic unit, preventing immediate full motion of the contacts when the coil is either energized or de-energized.
This addition provides the ordinary relay with time-delay actuation. Time-delay modules are constructed to delay armature motion on coil energisation, de-energisation or both.
A relay with such an accessory becomes a timer and is illustrated with a timer symbol.
