Wire overload?

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  #1  
Old 06-28-06, 03:47 PM
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Exclamation Wire overload?

I am wiring three motion detecting lights to my exterior.

They have their own place on the breaker and I am using 12 nm interior with 12Ufb exterior. There is also an infrequently used outlet hooked up to this circuit.

So basically 3 120V motion detecting lights and an infrequently used outlet.

Do I have too much hooked up together
 
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  #2  
Old 06-28-06, 05:26 PM
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Our code in NC limits you to ten items per circuit even on a 15 amp which uses #14 wire. If you put normal sized light bulbs in the motion lights you should be fine since you only have four items on the circuit.
 
  #3  
Old 06-28-06, 06:31 PM
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Originally Posted by fieldbenjamin

They have their own ... breaker
...
I am using 12 nm interior with 12Ufb exterior.

3 120V motion detecting lights...
an infrequently used outlet.
Assumptions:
20A breaker
(2) 100W bulbs = 200W per fixture * 3 fixtures = 600W
Not a long run of wire

For planning purposes:
20A load calc at 75% = 15 Amps
15 Amps * 125 V = 1875 Watts available
You are OK and should be OK for planning purposes.

At maximum load,
20A * 125V = 2500W
Less lighting load:
2500W - 600W = 1900W
With the lights on, you will have to pull about 1900W thru the receptacle to blow the breaker. You can probably manage this if you run a table saw, a shop vac and a circular saw at the same time as the lights are activated.

Make sure you use a GFCI recep or breaker if required.
 
  #4  
Old 06-28-06, 08:23 PM
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thank you!

thank you both!!!

It is a long run of wire, but I shoul be ok I think based on what you say
 
  #5  
Old 06-28-06, 08:59 PM
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Exclamation Just a little more help!!

I wired from the breaker....to a switch....directly out to the first light. The rest will be in series.


1. Do I need gfci somewhere in the line?

2. Is it ok to tuck UFB wire under my vinyl siding in a spot where I dont want conduit visible?
 
  #6  
Old 06-28-06, 09:34 PM
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GFCI , Yes on yor receptical.

Items in series, NO, They are in parallel.
 
  #7  
Old 06-28-06, 09:46 PM
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I dont have a receptical. It goes from the attic straight into the first light. Should I put one in the basement somewhere?

Also, from the junction box of the first light the next two will be connected....is this ok?

is it ok to tuck the wiring under the siding to be inconspicuous in a small area?
 
  #8  
Old 06-29-06, 05:21 AM
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The UF cable cannot be exposed, nor can it be tucked under the siding.

The terms serial and parallel really should not be used when discussing eletrical wiring. They only serve to confuse people. Electrically, ALL your loads are in parallel, so that each load gets 120 volts across it. However, physically your loads are in series.
 
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