I am running 10 gauge wire to my dock which will be about 100 ft from the disconnect box on the house to the dock. I will be providing electricity to a 1/2 hp hoist, which runs on 110, that will only run a few minutes at a time, a 75 watt light bulb, and a ceiling fan to be used occasionally. What size breaker do I need to use? I was told I could run 220 to the dock. If I do that will I have to have a breaker box on the dock to split into two separate 110 circuits? Florida location.
Electrical – How to run a dock circuit and what size breaker will be needed
electricaloutdoor
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Wiring from garage panel to welder
NEC 630.11(A) may be of interest.
National Electric Code 2008
ARTICLE 630 Electric Welders
II. Arc Welders
630.11 Ampacity of Supply Conductors.
(A) Individual Welders. The ampacity of the supply conductors shall be not less than the I1eff value on the rating plate. Alternatively, if the I1eff is not given, the ampacity of the supply conductors shall not be less than the current value determined by multiplying the rated primary current in amperes given on the welder rating plate by the factor shown in Table 630.11(A) based on the duty cycle of the welder.
Also take a look at 630.12 Overcurrent Protection.
The Owners manual (PDF) seems to contain the answer.
Wiring from service panel to sub panel
If we look at 110.14(C) in 2008 NEC, it says:
National Electrical Code 2008
ARTICLE 110 Requirements for Electrical Installations
I. General
110.14 Electrical Connections.
(C) Temperature Limitations. The temperature rating associated with the ampacity of a conductor shall be selected and coordinated so as not to exceed the lowest temperature rating of any connected termination, conductor, or device. Conductors with temperature ratings higher than specified for terminations shall be permitted to be used for ampacity adjustment, correction, or both.
Which means we'll have to check the breakers temperature rating, and the subpanel terminals temperature rating. Then we'll have to look at table 310.16 (Table 310.15(B)(16) NEC 2011), so we can determine the wire size we should use.
In this example image you can see if we're using copper, we'll use 60°C. Once we look at the table, we'll see that for 50A @ 60°C we need 6 AWG copper wire. (50A @ 75°C = 8 AWG).
110.14(C)(1)(a) basically says that if the temperature is not listed, use 60°C for circuits less than 100A. 110.14(C)(1)(b) says if the temperature is not listed, use 75°C for circuits over 100A. However, in the real world 75°C is often used for both.
Each baseboard heater is probably 15A (if not then check what they actually are), and the dryer is 30A. So you're already at 90A. The washer (is it frontloading?) will need 15A/2 (it's 120V), and so will the bathroom, so that's 105A. I can easily imagine all those running at once. Then you have some plugs and whatnot, but you probably won't max all of them at once.
Looks like 120A will be OK, but just barely. Is electrical heat really your only option? Can you use a gas dryer?
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Best Answer
30 amp breaker. Full load current on the motor is about 10 amps, plus a couple more amps for the other stuff gives you a voltage drop of 2%, less than the allowed 3%, so you're OK. You can run 220 as 2 branch circuits with a shared neutral. It's not really 220 because you can't power 220v equipment, but the voltage between the hot legs of each circuit is indeed 220v. You don't need breakers at the dock for this configuration, but you will need 3 conductors plus ground and a handle tied tandem breaker at the house panel.
Every thing will run fine on one circuit, so there is no advantage except you get 2 circuits. The voltage to ground is the same either way, so there is no added efficiency for the extra voltage.