Wire passing through insulation allowed?
- Thread starter cppoly
- Start date
- Status
Sierrasparky
Senior Member
- Location
- USA
- Occupation
- Electrician ,contractor
Sure,
Wire you mean NM or AC cable or...*** not just individual conductors not in cable or conduit.
Is there another concern?
Wire you mean NM or AC cable or...*** not just individual conductors not in cable or conduit.
Is there another concern?
Yea NM or another multi conductor cable. My concern was if a cable gets hot this would this be a concern if it's touching insulation? What about insulation coming into contact with a recessed panelboard, is there a minimum distance from insulation to a recessed panel in a wall? If conductors aren't terminated properly in panel that has insulation touching it I would think arcing could be a problem if insulation is nearby. Or no?
jaylectricity
Senior Member
- Location
- Massachusetts
- Occupation
- licensed journeyman electrician
90 degrees Celsius is pretty hot. Like really hot. But not hot enough to light insulation on fire.
I agree with Jay.
90 Deg C is really hot, but have you ever seen a NM cable get to that point under normal use? So, to the OP NM cable through insulation is safe and OK. You can also have insulation right next to the electrical panel.
NO PROBLEM.
Cavie
Senior Member
- Location
- SW Florida
RX is installed on the bottom cord of the trusses. Blown insulation is installed 6" to 18" thick. RX is completely covered. Spray foam insulation is also used. Sprayed on walls and bottom side of roof. Grows and completely envelops the RX.
- Occupation
- Licensed Electrician
I did my own remodel and insulated my exterior walls for thermal reasons and my interior walls for sound dampening so all the NM in my house is in contact with insulation. I'm not worried.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
Please see 334.80 which covers your application
Pierre C Belarge
Senior Member
- Location
- Westchester County, New York
If AC cable is installed in thermal insulation, the conductors are required to be reduced in ampere rating to the 60 degree C column. 320.80(A)
This would more or less affect feeder size cables from 8 AWG and larger.
This would more or less affect feeder size cables from 8 AWG and larger.
mopowr steve
Senior Member
- Location
- NW Ohio
- Occupation
- Electrical contractor
Isn't this the whole concept behind the article that states type NM in dwellings must use the 60* column or in other words showed highlighted
14awg=15amps
12awg=20amps
10awg=30amps
because it is automatically assuming that these wires will at some point encounter insulation.
as the base calculation for 12awg starts out at 30amp capability at 90*C
So the NM is already derated to deal with insulating effects.
14awg=15amps
12awg=20amps
10awg=30amps
because it is automatically assuming that these wires will at some point encounter insulation.
as the base calculation for 12awg starts out at 30amp capability at 90*C
So the NM is already derated to deal with insulating effects.
- Status