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View Full Version : 86 lockout rolls, no load on breaker



DLWood
October 7, 2022, 07:14 PM
Customer complaint: 86 lockout rolls to tripped position, breaker is open, load side of breaker has new ATS installed on load side of 4160D-480/277Y transformer. As of right now I see no reason to investigate the load side of the breaker. No flags from the electromechanical relays, (3) 50/51 and (1) 50G. Considering faulty 86 mechanism or control circuit? any thoughts?

gasman
October 9, 2022, 04:09 PM
Customer complaint: 86 lockout rolls to tripped position, breaker is open, load side of breaker has new ATS installed on load side of 4160D-480/277Y transformer. As of right now I see no reason to investigate the load side of the breaker. No flags from the electromechanical relays, (3) 50/51 and (1) 50G. Considering faulty 86 mechanism or control circuit? any thoughts?

Check the target coil tap. If it is set to 2 amps they usually won't drop on the current needed to roll a lockout coil. Mechanical targets can also be misadjusted and not drop. Don't assume the 86 is defective, if you don't do a thorough investigation and close in on a fault you will have lots of explaining to do.