Amperage/Cord Power question

ear3

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My knowledge of electrical is limited -- not much beyond the charts you find on the back of extension cord packaging telling you amp limits for specific cord lengths.

So at the jobsite I just moved into, the power situation is going to be pretty poor until we get someone in to do some work -- site hasn't been used in a few years, and currently I have one working outlet about 75 feet away from my work station, though it's run off a 20amp circuit.

I've run a 100 foot 10 gauge extension cord to draw power, but am wondering whether I might need to do another.  Here will be the basic load I'm putting: Kapex + CT, 1000 Watt worklight, and then the occasional reload of the PC portable air compressor.  There's also a portable fan and a Milwaukee radio/battery charger -- oh and a small fluorescent sign.  Given that the Kapex/CT and compressor draw will be intermittent (and will rarely, if ever, run at the same time), do you think I will be good on a single 100ft 10 gauge cord for right now?

Also, am I correct in assuming that the danger of tool motor degradation is not so much from overloading a circuit but rather when you use insufficient gauge cords to run power?
 
  I think the 1000w work light is going to be the problem when on the same circuit as the rest. Is there something you can do to use a light with (much) lower wattage draw? You may need to turn the CT down to reduce draw. The 10ga  cord is a good call.

Seth
 
As Seth said, the 1000 watt lighs will be an issue. I'd check into LED bulbs that replace the halogen light bulbs. They fit in the same space but cut the load to around 150 watts. You then also don't have the horrible/dangerous heat issues that you have with the halogens.
 
A 120V/20Amp circuit can only put out 16Amps continuous, which is about 1920 Watts. The Kapex can pull 1620 watts by itself (although that's not continuous).  At full speed the CT can pull 1200 Watts.  That means those two alone will take up pretty much the whole circuit.  Definitely will be a problem putting the 1000 watt light on the same circuit, and depending on how big the air compressor is, it could be a problem too. 

The 10 Gauge extension cord won't be an issue, the wires feeding the outlet are probably only 12 gauge.
 
[member=37411]Edward A Reno III[/member]
Bits & pieces: [2cents]
Festool recommends using a 10 gauge cord on the Kapex for distances of 50-100 feet. [thumbs up]
A 10 gauge cord is rated at 30 amps.  [thumbs up]
As [member=12048]jaguar36[/member] stated, a 20 amp breaker is derated to 16 amps (80%) for continuous (3 hours use) work. [crying]
A CT uses 2.9-10 amps. [big grin]
A Kapex can use up to 13 amps max.  [sad]
The 1000 watt halogens use 8.3 amps. [sad]
The 150 watt LED's use 1.25 amps. [thumbs up]
Most PC compressors are rated at 10 amps.  [sad]

So my take-away is, the Kapex and CT will work because they are intermittent. The compressor is also intermittent.
The halogens will be continuous and that's fine unless the compressor kicks in or you decide to use the Kapex. (I'd still change out the halogens for LED.) [big grin]
Run the Milwaukee radio on battery power and it's off the grid.
The portable fan (1 amp?) will also probably be ok, you just never know.

Is this 20 amp service on breakers of fuses? If fused, I'd suggest having a box or two of replacement fuses because things will happen.
 
Thanks.  I decided just to hold off with the work light.  There is enough ambient light for the moment to do the first part of the set build -- especially since I only had to measure once at the beginning to set my stops and then just cut, cut, cut.  Hopefully they'll have the power situation figured out when I move to building the finer, trickier work, where I'll be measuring and fitting quite a bit.
 
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