we have a generator shunt trip breaker 400 amp, 480 volt. it is an ITE JL-ETI-ET9600. The coil is burned up, and the customer wantes the whole unit replaced, but we suspect there may be a wiring problem, since someone was performing mainenance on it when the breaker started smoking. There are no diagrams available (those pages are missing from the manual). the 17 wires are 3 for the line, 3 for the load, two for the shunt coil, and there are three sets of dry contacts which account for the other 9 wires two of the sets of dry contacts change position when the breaker changes from on to off, and the other set changes position when it trips. There is a single pole DC breaker on the control panel, and when it is turned on, the coil engages, but the breaker does not trip. eventually the coil starts smoking. the maintenance guy says that normally when the DC breaker is turned on, the 400 amp breaker trips, but this doesn't sound like how it should work.
there may be a mechanical problem that prevents the coil from tripping the breaker, and since the coil is only intended to be energized momentarily it has burned up, but why would turning the control voltage on automatically shunt the coil? We can get a replacement for the breaker, we are just trying to avoid damaging the new one due to a pre-existing wiring problem. If anyone has any ideas we would welcome them.
there may be a mechanical problem that prevents the coil from tripping the breaker, and since the coil is only intended to be energized momentarily it has burned up, but why would turning the control voltage on automatically shunt the coil? We can get a replacement for the breaker, we are just trying to avoid damaging the new one due to a pre-existing wiring problem. If anyone has any ideas we would welcome them.