we have snychrounous motor unbalance current and trip when start we check insulation resistance all ok winding coil resistance balance .with all 3 phase motor 4.16 kv 600A full load breaker also ok did anybody have idea why it have unbalance current..
How are you starting it? Across the line, softstarter, vfd? Have you megger tested the motor? Also have you checked the excitation voltage.
hi darrin across the line with 4.16kv vacum circuit today we check all the megger all ok and check the relay it showns the ground current is the one trigger the tripping coil also today we check the ground ct 50:1 ratio and it looks all ok at it trips 13A ground current
