Connecting Several Motors on One Load

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SantiSpark

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Location
Colorado
Occupation
Electrician
So I'm doing a side job that is not to be inspected, but I also want to make sure it is a legit and most of all SAFE installation. There is a pond being built that will have 2 plug in motors (120v-12.7 FLA each). I was planning on running #10s to it and terminating on a 30A breaker. Then plugging both of the motors into a 20A receptacle on the load side of a 20A GFCI receptacle. Is this acceptable? Any tips would be greatly appreciated.
 

augie47

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Location
Tennessee
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State Electrical Inspector (Retired)
Do you know if the motors have thermal protection ?
(Nameplate data would be helpful)
The 30 amp circuit might well be undersized for the 2 motors together.
The plug & receptacles would need to be properly rated including HP rated.

(side note: any wiring installed without inspections especially where bodies of water are involved has a HUGE liability risk)
 

SantiSpark

Member
Location
Colorado
Occupation
Electrician
Do you know if the motors have thermal protection ?
(Nameplate data would be helpful)
The 30 amp circuit might well be undersized for the 2 motors together.
The plug & receptacles would need to be properly rated including HP rated.

(side note: any wiring installed without inspections especially where bodies of water are involved has a HUGE liability risk)
Not sure if thermal protected. And what would you suggest?
 

don_resqcapt19

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Staff member
Location
Illinois
Occupation
retired electrician
So I'm doing a side job that is not to be inspected, but I also want to make sure it is a legit and most of all SAFE installation. There is a pond being built that will have 2 plug in motors (120v-12.7 FLA each). I was planning on running #10s to it and terminating on a 30A breaker. Then plugging both of the motors into a 20A receptacle on the load side of a 20A GFCI receptacle. Is this acceptable? Any tips would be greatly appreciated.
See 210.21(B)(3)....that is not permitted.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
What you COULD do is run a 30A circuit out to a little outdoor rated sub-panel with a couple of 20A GFCI breakers in it, feeding 20A receptacles (or regular breakers feeding 20A GFCI receptacles). But again, IF the motors are thermally protected. If not, you will need OL protection, so you could put in a Manual Motor Starter for each one.

Start with the details on the motor, it has to begin there.
 

Russs57

Senior Member
Location
Miami, Florida, USA
Occupation
Maintenance Engineer
The way I see it.

A 30 amp breaker shouldn't have more than a 24 amp load. You will be over that. A 20 amp breaker can be loaded to 16 amps. You will be under that with one motor. So put each motor on it's own 20 amp breaker. I.E. run 4 #12's instead of 3 # 10's and use a MWBC.

If wire is in conduit, and your locale allows the conduit to be the ground, maybe you just swap a 30 amp single pole breaker for a 20 amp double pole and you are good to go.
 
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