fixed electric space heating

[Nickjungwirth1]

Ok, I have a FLA 75 amp portable heater on wheels 3 phase 480v. Im going to be feeding it off of an MCC to a 100 amp fused disconnect. RIght now I consider this a continuous load and thus needing to be x125 percent OCPD. so about 93 amps which would need a 100 amp bucket, My question is does this require the conductors from said MCC bucket to be sized at 125 percent as well?

 

[infinity]

Yes fixed electric space heating equipment for conductor sizing is considered a continuos load.

 

[electrofelon]

The phrases "portable heater on wheels" and "fixed electric space heating" seem to clash a bit . That said, it would still be considered a continuous load if used for three hours or more.

 

[infinity]

424.3(B) requires the branch circuit to be considered a continuous load even if it does not run at full continuous output for three hours or more. 590.2(A) would require that the branch circuit be sized according to 423.4(B) even if the heater were temporary because the heater requirement is not modified by Article 590, Temporary Installations.