Run 100 Amp Wire Under Roof

Need to carry 100 amps 500 feet.

Run 100 amp wire under roof.

On 2019 03 28 by mod paul more detailed wire sizing help including run length and wire size increases are at se cable sizes vs amps. Looking for the right size wire for your 100 amp sub panel for a detached building garage or shed. A 100a breaker would require a 8 cu or a 6 al. You ll need two wires one white and one black for one circuit or more if you intend to wire a three way switch from the house or add more than one circuit.

The cable must contain one or two hot wires depending on your needs one neutral wire and one ground wire. What sz of direct burial wire for 200 amp service 200 away coming from on the ground transformer. When it comes to the lines connecting master and secondary panels where the line will carry as much as a full 100 amps use a 2 gauge non metallic sheathed electrical cable. You need a 3 3 3 5 copper ser cable to carry 100 amps that s three 3 gauge for the two hot wires and the neutral and a 5 gauge for the ground.

Single conductor 3 gauge thhn. Your grounding conductor must be run also and it is sized to the breaker also. Assuming the voltage is 240 volts the wire size for a 100 amp panel at the end of 400 feet and holding the voltage drop to 3 the wire will be 3 0 in size. Someone stated the 100 amp panel won t take the wire size.

I m wiring a 100 amp garage sub panel from a 200 amp main in my house. On 2019 03 20 by paul. If you want to use aluminum you need at least 2 gauge or perhaps 1. Each wire should be 2 gauge in size.

Use thwn 2 14 gauge stranded wire if you get power from a 15 amp circuit or thwn 2 12 gauge stranded wire for a 20 amp circuit. The next logical size is 250mcm which will go 383 foot. Data from the gould shawmut book of electrical information. If you are calculating full load then the grounding conductor must take voltage drop into account and rise a full two sizes more just like the current carrying conductors or a 4 cu or 2 al.

The run to the garage lug to lug is 65 and i have to bury the cable to meet code and am going to put it in sched 40 conduit. Per the i a e a table 4 0 copper will go 323 foot before the voltage drops 3 from your nominal. 1 3 thhn thwn 2 wire for 100 amp sub panel. 100 yards 300 foot.