Maximum circuit size

[frosty fingers]

I have an electrician who has installed the circuit feeding my 15 ton package unit. The unit's label say a max of 50 amps. He installed 60 amp breakers. I told him the label applied and that he needed to change them to 50 amp. He won't budge, he is claiming an allowance in the NEC section 440.22. which one applies?

[mustardman]

It may be ok in the electrical code in your area however if the manufacturer specs 50 thats what it should be as they have determined what size protection they require. I would be willing to bet warranty would be affected with a 60 amp installed. I know we would void it. Have a letter drafted stating the warranty will be void and hand a copy to the sparky and the building owner. Bet the breaker is changed within the hour.

[theycallmethefireman]

Refer him 440.35

I just did a quick glance is all.

[Coolmaniac]

Would he not be kosher if the units disconnect has 50 amp fuses?

[techtalker]

section 440-22 of the code, section C states that the protective device rating will not exceed the manufacturer's values. so the electrician need to read a little bit further.

[pipefitter636]

Would he not be kosher if the units disconnect has 50 amp fuses?

He would be kosher if in fact the unit does have it's own disconnect and fused at 50 amps.

[flyrfan]

My understanding is that the breaker at the panel protects the conductorsfeeding the appliance. If an overcurrent protection device is reqd to be field provided, then the rating of that device must not exceed the MOCP or MCA rating of the appliance.