ocpd for 2 motors

[Fishin-trician]

Circuit feeds a boat elevator controller with 2-1 hp motors, wired @ 230 volts. No fla or flc listed on the nameplate, only says 6.7 amps. No overloads on either identical motor. Manufacturer recommends a 15 amp, but only 20 amp gfi is available local.
Art. 430 has always been confusing for me; can I go with the 20 and be compliant?:-? Thanx in advance for any replies.

 

[Dennis Alwon]

Is the manufacturer recommending a 15 amp for both motors on the same feed or 15 amp for one motor? I would not put both motors on a 15 amp cir.

 

[Fishin-trician]

Is the manufacturer recommending a 15 amp for both motors on the same feed or 15 amp for one motor? I would not put both motors on a 15 amp cir.

The controller mfgr. is recommending 15 amp, 230 volt ocpd for both motors. I ran the lift to test with a 15, but didn't check amps with a probe, and there was not a boat on the lift.

 

[augie47]

110.3(B) is pretty much a "golden rule". By Code, you have to install per manufacturer instructions included in the listing and labeling. The maximum OCP most likely fits that requirement.

 

[Dennis Alwon]

110.3(B) is pretty much a "golden rule". By Code, you have to install per manufacturer instructions included in the listing and labeling. The maximum OCP most likely fits that requirement.

If they recommend it, I don't think that you have to --- do you?

 

[Fishin-trician]

110.3(B) is pretty much a "golden rule". By Code, you have to install per manufacturer instructions included in the listing and labeling. The maximum OCP most likely fits that requirement.

That is what I usually go by. In this case the mfgr. gives a chart for all different motor makes, amount and sizes. The motors are supplied by the lift contractor. At the bottom of their chart is the wording "breaker size is our recommendation. Please use motor label for proper size and code compliance. Which, got me searching, and thinking(prob. over-thinking), then posting for some other view points.
430.248 (nec 08) gives me 8.0 amps for the flc, 2x8=16amps, next size up is a 20 amp ocpd. Don't think 430.22 comes into play without overloads on motors.
I'm using the 20 gfi for a final tomorrow, as that is only available, we'll see what the ahj has to say.

 

[TT009]

430.248 (nec 08) gives me 8.0 amps for the flc, 2x8=16amps, next size up is a 20 amp ocpd. Don't think 430.22 comes into play without overloads on motors.
I'm using the 20 gfi for a final tomorrow, as that is only available, we'll see what the ahj has to say.

With you having two motors you would follow 430.24, 8*125%+8=18A, so you would have to run a min. 14awg not calculating VD.

Do you have a controller by these motors? Or are you adding a starter w/disconnect for the two motors?

If a controller and it specs no larger than a 15A OCPD you should follow that, if you are adding a starter w/disconnect you would be allowed to put on a 20A OCPD according to 430.52 or 430.62.