1hp single phase motor 50 /60 hz conductor and cord cap sizing

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centric

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What is the correct conductor and cord cap size for a 1 hp 115volt single phase motor with the following motor name plate data.
this motor is rated continuous duty. S.F. 1.5 50 HZ system 115VAC 14.0 AMP s.f.a / 60HZ system 19.4 AMP s.f.a this is an internal overload protected motor the manufacturer states that the overload is sized 10 % above full load. protection code 0015.
 
50 hz 60 hz motor conductor sizing

50 hz 60 hz motor conductor sizing

ptonsparky said:
What have you come up with?
Click to expand...
Currently it's being wired with SOW #14 with a 15 amp cord cap. I disagree with the senior engineer, from my
calculations it should be at least a #12 SOW and a 20 amp cord cap. This motor drives a hydraulic pump which runs continuously.
 
centric said:
Currently it's being wired with SOW #14 with a 15 amp cord cap. I disagree with the senior engineer, from my
calculations it should be at least a #12 SOW and a 20 amp cord cap. This motor drives a hydraulic pump which runs continuously.
Click to expand...

Does this motor need to be moved or serviced frequently?

Table 400.5(A)(1) indicates #14 SOW has an allowable ampacity of 15.

430.109(F) reference the HP rating of the attachment plug and cord connector.

Both are from the 2011 NEC. My 2017 is in the garage and that is too far this morning.
 
centric said:
Currently it's being wired with SOW #14 with a 15 amp cord cap. I disagree with the senior engineer, from my
calculations it should be at least a #12 SOW and a 20 amp cord cap. This motor drives a hydraulic pump which runs continuously.
Click to expand...

In principal, I agree with you on the 12ga SOW cable, though 14ga would probably be fine. Is the motor being fully loaded at all times? From a practical point of view, there's no physical difference between a 15A and 20A straight-blade cord cap; only the pin is rotated 90 deg in the 20A plug.

I'm guessing you'll have nuisance tripping issues with this setup if it's connected to a 20A circuit, and definitely if it's connected to a 15A circuit. Either places you well beyond the 80% mark to which you're supposed to load a continuous circuit. A 30A circuit with 10ga SOW cable and a L5-30 Twist-Lok cord cap is the way to go here. How much more could it possibly cost to design it conservatively, so there's no chance of a callback for breaker tripping?



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