摘要 |
An electromagnetic relay is provided with a high current "boost" coil, a lower current normal operating or "seal" coil and a static, electronic circuit that functions under low voltage conditions to energize the boost coil to retain the relay closed. An additional function of this static, electronic circuit is to energize the boost coil for a time interval on initial power application in order to assist in closing the relay, and this time interval automatically varies in the correct direction with variation in the supply voltage available to the coil so that the lower such available voltage is from its normal value, the longer the boosting time interval. At other times, both coils are energized in series at low current to hold the relay closed. This static, electronic circuit is small enough to be integrally incorporated within the housing of a conventional sealed power relay.
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