"In parallel operation of Diesel generator case the neutral potential of the each DG will differ one to other, when we paralleling the DG's only one neutral should be present in the bus bar because if we connect multiple neutrals due to potential difference the control system will deduct circulating current and trip the circuit breaker immediately. hence in synchronization the neutral contactor of master DG only will be in closed condition, other follower DG's will run in floating condition. due to this only we are using 3 pole breaker + neutral contactor"
From the above points can any body tell me which relay has been used in the sync panel to open the neutral contactor?