An arrangement for controlling the operation of switch contacts.

摘要

The arrangement comprises a device for providing a signal indicating that operation of the switch contacts is required. A timer is arranged to provide a second signal at a time indicative of a zero crossing of an alternating voltage being switched by the switch contacts. A circuit delays the second signal to compensate for mechanical and/or electrical inertia or an operator for the switch contacts. A device energises the operator in response to the first and second signals so that operation of the switch contacts will occur at or near to a zero crossing of the alternating voltage. The invention is used in ac mains stabilisation and in transformer tap changing motor.