malachi constant
Senior Member
- Location
- Minneapolis
How do you size a feeder and OCPD for a propane vaporizer? What article applies? Installation is in upper midwest (cold weather). Propane tank is exterior and the propane is used to heat building. From what I understand the vaporizer may at times run continuously in winter months.
FLA is 32.5A at 308V/3P. At first I was not told this was a vaporizer - only that it was electric heat, and that the electrician had installed #8 CU w/ #10 ground on a 40A breaker, and wouldn't I please verify that they got it right. Assuming it was electric space heat I told them 32.5 x 1.25% = 40.63, and that a #8 won't work unless lugs are rated 75C, and the 40A OCPD needs to be changed to a 45A or 50A.
Now I understand it is not space heat, but as it is a continuous load I assume my statement stands. Am I right?
As for which article technically applies...I hesitate to use article 430 as this isn't a motor, and 424, 426, 427, 440 etc don't seem to apply either.
Thanks!
FLA is 32.5A at 308V/3P. At first I was not told this was a vaporizer - only that it was electric heat, and that the electrician had installed #8 CU w/ #10 ground on a 40A breaker, and wouldn't I please verify that they got it right. Assuming it was electric space heat I told them 32.5 x 1.25% = 40.63, and that a #8 won't work unless lugs are rated 75C, and the 40A OCPD needs to be changed to a 45A or 50A.
Now I understand it is not space heat, but as it is a continuous load I assume my statement stands. Am I right?
As for which article technically applies...I hesitate to use article 430 as this isn't a motor, and 424, 426, 427, 440 etc don't seem to apply either.
Thanks!