We had a motor fail on a critical pump this morning. It is a 125 HP vertical inline pump, 1800 RPM, motor can be wired 230 or 460V, we run the pump at 460 V.

Under the cathead we found that one of the leads we would use if we were to wire it for 230 V had worn through and was burnt. We beleive the failure was due to a short of this wire due to vibration and or heat in the motor.

We are having the motor rewound and have asked the motor shop if the motor can be rewound just for 460 V and eliminate the alternate leads for 230 V operation.

Our thinking is that we would never need to run the pump at 230 V and we can eliminate a potential failure mode by doing it this way. I think we can also free up some space under the cathead and lower the risk that the 460 V leads that we actually use will short due to insulation wearing through because of limited space under cathead.

Any chance there are some negatives I am missing with this plan?

Thanks,

John

I don't see any negatives.

OK, technically, someone could argue there may be small benefits to extra leads available during motor testing. But I doubt anyone would ever use that capability even if you have it. And assuming you don't have any 230v applications, you would never have any need for those other leads.

There are no negatives. Have the motor shop either replace the nameplate or stamp out the lower voltage rating and related current so that there are no issues in the future.

Howard

Pete and Howard - Thanks for your responses.

John