Subpanel a bad idea?

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  #1  
Old 07-28-14, 04:32 PM
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Subpanel a bad idea?

I have a 3/4" EMT conduit that runs from the main panel to the kitchen area with #6 conductors that used to be for the range. Now that the range has been split - the oven relocated to a different wall, and a new cooktop, both with their own dedicated circuit and wiring - I no longer need this run of the #6 conductors.

However, I do need to run three 4 new circuits to that kitchen wall - one for the range hood, one for the dishwasher/disposer, and two for counter receptacles.

Thinking loud here, instead of deleting/canceling the line to the old range, should I consider putting in a 4 circuit sub panel and run the DW/disposer/receptacles/hood from that sub panel? That way I don't need to run 4 sets of wires back to the main panel, and having to throw away the existing #6 wires, which is about a 65' long run?

Issue I see is I think for a subpanel it needs to be fully accessible right? Can it be inside a kitchen wall cabinet? Even if I don't put anything in that cabinet it is still an awkward access I think...
 
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Old 07-28-14, 04:44 PM
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It would need to be accessible. Usually a panel requires 30" of clear area so that the panel can be worked on properly.

You would also need 4 wires to your sub panel.
 
  #3  
Old 07-28-14, 04:45 PM
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Yes you may ......if the pipe has 3 wires you have a 120 volt run....if the pipe has 4 wires you have a 240 volt run.

You may not put the panel in the cabinets.

If you can pull the 4 runs easy it is probably the best way to do it.
 
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Old 07-28-14, 05:13 PM
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The range was a 240V range so it's currently on two pole 50A breakers, a red, a black, a white neutral and a green ground conductor.

If I can't put a sub panel inside a cabinet then it's not going to work. I can't think of a spot that would be accessible and yet not being an eye sore in the kitchen.
 
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Old 07-28-14, 05:52 PM
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You might be able to use it for a hot tub some time
 
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Old 07-28-14, 06:01 PM
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You can install a j box at the end of that #6 and take off with 2 120 volt circuits. Change the breaker


if you can pull the #6 out............extend the pipe to a 2gang box........

You could pull 9 # 12s for 4 120 volt circuits.

3/4 pipe will take 17 or 18 12s
 
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Old 07-28-14, 07:26 PM
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Subpanel a bad idea?
Yes, a bad idea. You can use that conduit to pull the circuits you need as long as it remains accessible, but you don't have the necessary space for required clearance for a subpanel.
 
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Old 07-28-14, 09:14 PM
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You could pull 9 # 12s for 4 120 volt circuits.

3/4 pipe will take 17 or 18 12s
How do you do that? 17 or 18 #12s? With 4 circuits I need 8 #12s. I don't need ground as the conduit acts as ground. I think 8 #12 will be really jammed tight. If I share the neutral by putting the circuits on opposite legs I can get by with two less neutral conductors, total 6. I am not sure I can pull 8.
 
  #9  
Old 07-29-14, 05:18 AM
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get a 500 ft rl of thhn 12 gauge stranded wire in black and white...pull the 6.....

add conduit to get to a nice location for a j box...............counter top outlet or .j box only................ you can put a j box in a cabinet...............measure how long your wires mubt be old pipe( the #6) the pipe you added .....add 2 or 3 ft for each end.............

cut 4 length of black and 4 white wires


hook a string( 1/8 in nylon rope) to the ground wire in the pipe and pull the string into the pipe as you pull the wire out.

use the string to pull the 8 12 s into the pipe...........put lots of wirelube on the wire to help it pull easy.


you may pull 16 number 12 wires in a 3/4 in pipe.

8 wires will be an easy pull...............the harder part might be to pull the old wires out.
 
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Old 07-29-14, 07:14 AM
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Derating issues would apply to that many conductors in the conduit.

To Miami, the code may allow that many conductors in a conduit. That does not mean it will be easy. Additional conductors after the initial installation will be even more difficult.
 
  #11  
Old 07-30-14, 03:20 PM
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NEC 2014 has 210.8(D)........your dishwasher must be GFCI protected

NEC 2011 has NO 210.8(D)

NEC 2008 has NO 210.8(D)





read the electric code for yourself .ASK THE BUILDING DEPT. WHICH CODE TO USE....

the great state of Florida is still using the 2008 NEC.
GOOGLE NEC pdf 2014

GOOGLE FOR 2014 CODE https://archive.org/details/nfpa.nec.2014

GOOGLE FOR 2011 CODE https://archive.org/stream/gov.law.n...ge/n0/mode/2up

GOOGLE FOR 2008 CODE https://archive.org/stream/gov.al.el...ge/n7/mode/2up
 
  #12  
Old 07-30-14, 05:38 PM
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Yes we must derate the amp of the wires

lets see...............

NEC 2008 310.14 (B) (2)

NED 2014 310.15 (B) (3)

12 GAUGE THHN or THHW COPPER IS RATED AT 30 AMPS.................

4 to 6 wires in one pipe............derate to 80%......24 amps.......20 amp breaker,circuit still good

7 to 9 wires in one pipe.............derate to 70%......21 amps......20 amp breaker,circuit still good

if the pipe is in the basement or under the attic insulation with ambient temperatures of 86 degrees F
or less no ambient derate is necessary.

With the load diversity we have in a house we generally do not have to worry about ambient temperatures

see annex B ,TABLE B.310.11


8 OR 9 12'S IN A 3/4 IN PIPE IS A EASY PULL...............YOU PULL ALL 8 OR 9 WIRES AT THE SAME TIME..........USE LOTTS OF WIRELUBE............

YOU HAVE TO DESIDE WHICH IS EASER IN YOUR INSTALLATION......IF IT IS EASY TO PULL 4 12-2WG nm,THAT IS WHAT I WOULD DO

RAY.......SORRY ABOut the caps,i do not mean to yell,i will work on harder.


read the electric code for yourself .ASK THE BUILDING DEPT. WHICH CODE TO USE....

the great state of Florida is still using the 2008 NEC.
GOOGLE NEC pdf 2014

GOOGLE FOR 2014 CODE https://archive.org/details/nfpa.nec.2014

GOOGLE FOR 2011 CODE https://archive.org/stream/gov.law.n...ge/n0/mode/2up

GOOGLE FOR 2008 CODE https://archive.org/stream/gov.al.el...ge/n7/mode/2up
 
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