10kw heat strip disconnect

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Augie47 I see you are a retired TN electrical inspector and I am a retired TN State Trooper Lieutenant. I will look into the internal fusing, but
NEC 424.3 (A) also states: Individual branch circuits shall be permitted to supply any volt-ampere or wattage rating of fixed electric space-heating equipment for which they are rated. Does this cover my 80 Amp Circuit since this is the only thing on this circuit?
"I calculated the CB as 14,400/240 = 60A x 1.25 = 75A so I am using an 80A breaker."
 
SHAEF-Ike said:
Augie47 I see you are a retired TN electrical inspector and I am a retired TN State Trooper Lieutenant. I will look into the internal fusing, but
NEC 424.3 (A) also states: Individual branch circuits shall be permitted to supply any volt-ampere or wattage rating of fixed electric space-heating equipment for which they are rated. Does this cover my 80 Amp Circuit since this is the only thing on this circuit?
"I calculated the CB as 14,400/240 = 60A x 1.25 = 75A so I am using an 80A breaker."
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IT doesn't override the 424.22 requirement.
It's possible that there will be internal fusing so your 80 amp circuit will be acceptable but it may well call for (2) individual circuits in which your 80 amp circuit will need to feed (2) overcurrnet devices sized per nameplate.
The air handler should have a nameplate providing MinCktAmps and MaxOvercurrent.

(Check you messaging)
 
You've seen breakers come already mounted in a furnace. Like Augie said...
The one pictured has the cover off. When the cover is on. It will have a little black cover with a hinge. . I've mostly seen them for 15Kw heat. Just thought I'd throw that out their. Had the pic on my phone.
Screenshot_20211113-162424_Gallery.jpg
 
SHAEF-Ike said:
Hey folks! I am now going to be installing a disconnect and Circuit Breaker (CB) for a 15KW heat strip (heat strip only, no other load). Previous electrician ran a 2 cdr 4 awg 1 cdr 6awg NM copper wire for this install. The heat strip is actually 14,400 watts 208/230 volt. I calculated the CB as 14,400/240 = 60A x 1.25 = 75A so I am using an 80A breaker.

So again my question is 'What size non fused disconnect do I need to install?' Can I use a standard 60A disconnect down stream of an 80A breaker?
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We normally supply a 60a circuit and a 30a circuit for 15 Kw heat.
 
Some great answers here folks! Just to clarify I am only supplying a disconnect for the 15kw heat strip. The blower motor and low voltage is already hooked up and running from a 40amp circuit previously installed. An HVAC technician will be making the connections from the disconnect to the heat strip.
Do I need to build him a load center as previously suggested with 60 and 30 amp breaker’s. Or just use a 100 amp disconnect and let him spilt it in the appliance? I only have one cable with 2-4 awg and 1-6 awg wires to work with currently.
 
If you just leave the wire and it is terminated to a breaker.
Please installed j box and cap the ends label the junction box with the panel location and breaker number.

If wires just hung in two locations one by the panel and one by the HVAC air handler label the wire at each end.
 
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