Excitation contacts between the armature and the core working air gap is too large

Diesel use that often appear overly excited contactor LC action lags, or the master controller handle a blade and electric control contactor operation after only a few field contactor pull, sometimes even exceeding 35 or more, resulting in mistaken crew electrical fault in the process of elimination in the field contactor suddenly pull away car,   mcb circuit breaker crew working to bring some difficulties . Cause : Auxiliary interlock -delay . Excitation contacts between the armature and the core working air gap is too large. Activities are not flexible and exciter armature contactor moving contact and arc chute connected to ground caused by excitation contactor guilty cards. Field contactor auxiliary starting coil  air circuit breaker  or anti- interlock contacts being exposed . Analysis: field contactor switched on only after all the only action , if one is turned slowly interlocking coil is energized will cause lag . Auxiliary contacts connected, breaking contacts by electrically controlled solenoid valve on the air cylinder control contact air source to achieve, it is sometimes due to poor lubrication, air cylinder , electronically controlled contactor guilty card , electronic control contacts on the electrically controlled valve stem wear due to prolonged use too short , thimble or curved top side , so that the compressed air into the pneumatic air cylinder device channel becomes smaller ;