Old wiring questions


  #1  
Old 12-20-07, 09:57 AM
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Old wiring questions

Our house was built in 1947. It was wired with what appears to be 12ga BX. When the panel was updated 10 years ago all the fuses were switched to 20amp breakers.

I am doing some wiring and I had the occasion to remove a long stretch of the original BX on one of the circuits. When I took the wires out of the metal cable; the wires have printed on them 14 r - 600v - code grade; but the wires are thick like 12 ga wire. I even compared it to some new 12ga I have and some 14ga scrap that I have; it definetly looks like 12 ga and measures the same on a gauge.

Just like 2x4's used to be 2" x 4" was old 14ga wire as thick as 12ga of now? Should I be concerned that these are all on 20amp breakers because it has 14 written on the wire? Obviously, the electrician that re-did the box thought it was 12ga and also the inspector. Hmmm.

Any ideas, I would appreciate.
 
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Old 12-20-07, 11:22 AM
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You are measuring just the copper, correct?

The wire gauge has not changed, however, the insulation thickness has, in many cases, gotten thinner over the years.
 

Last edited by telecom guy; 12-20-07 at 11:23 AM. Reason: spellin kop
  #3  
Old 12-20-07, 03:21 PM
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I'm comparing the copper wire to the copper wire - not the insulation to the insulation; although yes, the insulation is giant too!!!
 
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Old 12-20-07, 06:16 PM
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That number may not mean anything about wire size. May just be a catalog number.
 
 

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