Elevator OCP

[Npstewart]

I have a project where an elevator changed from a 25HP to 50HP (208/3), midway through the project. Inititally, we had a 125A CB for the elevator feed, and a 2" conduit for the feeder. The max size CB that the electrician can get for the MDP without holding up the project is a 200A CB. How concerned would you be that this circuit breaker is going to trip?

50HP @ 208/3 is 143 FLA per NEC table 430, but according to the elevator shops, the FLA is 156 which likely takes into account the motor + controls etc...

The application is a furniture store and the elevator will likely be used fairly infrequently but I am concerned about the initial startup and filling the store.

I know this is kind of a loaded question.

 

[Ingenieur]

what type of motor control?
can inrush be limited?

can you get an adjustable motor circuit protector?

otherwise, yes, it may pose nuisance tripping isues

 

[Jraef]

I would HIGHLY recommend putting a soft starter on that motor. But be aware, elevator controls are a special beast, you must use one that has the proper approvals. Generally that is handled by the elevator supplier because the specially certified soft starters are often only made available through elevator OEMs. But with a soft starter, a 200A breaker should be fine.

 

[Npstewart]

Thanks guys. I was looking for some re-assurance and I found it.