A RELAY TEST DEVICE

摘要

A relay test device (24) for testing the state of a relay switch (39) is described. The relay test device comprises: a sensor (9) for testing the presence of an electromagnetic field emitted from a switch-controlling element (37) of a relay; and an indicating device (21) for indicating the presence of the electromagnetic field, in response to a sensor output signal. The test device (24) may be used in-situ within electrical systems whilst the relays are connected to other parts of the system.