Replacing a sewage pump for a building Existing panel is Challenger Electric J94 Company discontinued so unable to find amperage

I know the Voltage-Motor Horsepower rating information.See attached image with information

What is the amperage of the existing panel?

Looking to replace existing pump with a 3.8 Amp pump.

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This looks like a 3-phase contactor or motor controller wired for 240V single-phase (or to be more precise, split-phase).

This is not the service panel, it's not the circuit breaker and it has no bearing on circuit capacity. To get your answer on ampacity, you need to go look at the service panel where the breaker is.

Jusging by the motor amps you are mentioning, this thing should be more than able to handle the draw of your new motor.


Not sure if this is the info you're looking for, but a size 0 motor starter is rated 18A max continuous. Those FH34 heater elements should be good for 4.5A - 5A continuous load current

See Heater element chart


A size 0 starter can handle a 3hp 3 phase motor with the motor ampere rating of 9.6 amps at 230v with the heater rating of 11.04 amps. A 3.6 amp motor 230vsingle phase converts back to 1/3 hp so the contactor is big enough to carry the load. Those heaters are a bit oversized they are there to protect the pump motor they allow for ~10 seconds of high starting current (most pumps only take 1-2 seconds to get to speed) the reason I mention this is because I will usually use a smaller starter in this case like an fh30 or fh31 doing this I have very few motor failures, pump motors don't normally have much variance in draw once up to speed compared to other motor driven loads. With an over sized heater there is not much protection. For the motor and that is what they are there for. Can this handle the new pump? yes, is it properly protected ? No. At home I would probably not go to the expense of correcting the heaters but at work I would have the correct size.


Challenger no longer exists, but that was always a Westinghouse contactor and that part of Westinghouse is not owned and supported by Eaton. You can still get heater elements for it through them.

  • 1
    "is not", or "is"? – Harper Mar 7 at 18:06
  • This seems like a comment. It doesn't answer the question. – isherwood Mar 7 at 19:02

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