HELP! Can I run a 480V motor with dynamic brake disconnected

[wyopokesfan]

For testing purposes, can I disconnect the dynamic brake leads from my starter and see if the motor runs without tripping the breaker? Wanting to try and see if something has gone bad in the brake. Having issues with a motor tripping a 150A breaker as soon as it is started. Have eliminated pretty much everything except for the brake. This motor (old one) burned up two weeks ago. Blew two fuses on dynamic brake last week. Found the 150A breaker this morning only putting out 130V on phase A, with B and C phases at 277V. Replaced breaker, still tripping. Nothing shorted to ground, have continuity through all phases of motor.

 

[Jraef]

For testing purposes, can I disconnect the dynamic brake leads from my starter and see if the motor runs without tripping the breaker? Wanting to try and see if something has gone bad in the brake. Having issues with a motor tripping a 150A breaker as soon as it is started. Have eliminated pretty much everything except for the brake. This motor (old one) burned up two weeks ago. Blew two fuses on dynamic brake last week. Found the 150A breaker this morning only putting out 130V on phase A, with B and C phases at 277V. Replaced breaker, still tripping. Nothing shorted to ground, have continuity through all phases of motor.

DYNAMIC brakes are on VFDs. I suspect what you have is a DC Injection Brake on a starter. If so, it would have no effect on the starter, but if you disconnect it, the motor will coast to a stop. If you describe it better with mfrs and part numbers, I may be able to help more. Some brake units are absolute crap and if damaged, will do all sort of odd things.

 

[Besoeker]

For testing purposes, can I disconnect the dynamic brake leads from my starter and see if the motor runs without tripping the breaker? Wanting to try and see if something has gone bad in the brake. Having issues with a motor tripping a 150A breaker as soon as it is started. Have eliminated pretty much everything except for the brake. This motor (old one) burned up two weeks ago. Blew two fuses on dynamic brake last week. Found the 150A breaker this morning only putting out 130V on phase A, with B and C phases at 277V. Replaced breaker, still tripping. Nothing shorted to ground, have continuity through all phases of motor.

Can you post an electrical diagram?