What size wire do I need to run a 100 amp sub panel?

Asked By: Safa Aguedo | Last Updated: 26th March, 2021
Category: home and garden home entertaining
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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).

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Also, what size wire do I need to run a 100 amp subpanel?

A 100 A sub-panel requires a two-pole 100 A breaker - if you want 100 A. You can use #4 AWG 75 deg C or 90 Deg C copper wire in conduit for a 100 A breaker provided the breaker is labeled for use with 75 deg C wire.

Similarly, can you run a 100 amp sub panel off a 100 amp main panel? To the best of my understanding, there is no code issue running a 100A subpanel off a 100A main panel, so long as the wire size is correct, and the installation is correct. For a subpanel, you need four wire service (two hots, a neutral, and an equipment ground).

Likewise, people ask, how many amps can a 100 amp panel handle?

200 amps

What size wire do I need to run a 60 amp subpanel?

In practice, however, it's common to wire 60-amp breakers with 6-gauge, 3-conductor wire because an appliance that needs a 60-amp breaker seldom draws the full 60 amps. If you're installing a 60-amp subpanel, however, it's best to connect it to the main panel with 4-gauge wire.

39 Related Question Answers Found

Does sub panel wire need to be in conduit?

Re: Subpanel wire run
Individual THHN conductors must be run in conduit--either metallic or non-metallic, flexible or rigid. You could probably use SER instead, as long as it's sheathed and contains four conductors: one for Leg A, Leg B, neutral, and ground.

How many amps is #6 wire good for?

Size & AMP Ratings
NM, TW, & UF WIRE (Copper Conductor) SE CABLE (Copper Conductor)
14 AWG - 15 AMPS 8 AWG - 50 AMPS
12 AWG - 20 AMPS 6 AWG - 65 AMPS
10 AWG - 30 AMPS 4 AWG - 85 AMPS
8 AWG - 40 AMPS 2 AWG - 115 AMPS

What kind of wire do you use for a sub panel?

A subpanel requires two hot wires connected to a 240-volt double-pole breaker in the main panel. It also needs a neutral wire and a ground wire. The cable used for this run is known as a "three-wire cable with ground." The two hot wires, called feeder wires, will provide all of the power to the subpanel.

What size wire do I need for an 80 amp sub panel?

Schedule 80 PVC conduit would need to be 1-1/4" for 3 wire or 1-1/2 for 4 wire. In your sub Panel the ground and neutral needs to be isolated many times they are tied together at the factory with a large copper wire connecting the 2 grounded / grounding buss bars. Other than that you should bury this a minimum of 18".

How do you size a subpanel?


Subpanel Coverage Area
Measure the length and width of each room and multiply them together to find the square footage of the room. Add up the square footage of all of the rooms to find the total square footage. Multiply the total square footage by 3 (watts) to complete the calculation.

What size breaker do I need for a 125 amp sub panel?

If you have a 125 amp breaker you need 125 amp wire. See the table here. You need to use the 75° column since no one makes a 90° breaker just yet. Since this is a single phase dwelling service you can use #2 AWG copper or 1/0 aluminum for a 125 amp service or main feeder.

What size wire do I need to run a 100 amp service?

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. The cable must contain one or two hot wires depending on your needs, one neutral wire, and one ground wire. Each wire should be 2-gauge in size.

How many outlets can be on a 15 amp breaker?

for a 15 amp circuit this allowed for 10 outlets and on a 20 amp circuit 13 outlets were allowed.

Is 200 amps enough for a house?


200-amp service provides enough power for an electrical heating system, electrical appliances, plus general lighting and receptacle circuits. In large homes, 400-amp services are used with very extensive electric heating plus electrical appliances and lighting and receptacle circuits.

What wire do I need for 100 amp subpanel?

This is typically a three-wire cable with three insulated conductors plus a bare copper ground wire. The cable must have a wire gauge sufficient to the amperage of the subpanel—a 100-amp subpanel requires #4 copper wires, for example.

Does 2 100 amp breakers make 200 amps?

No. It is 100 amp. And the two 50 amps breakers that are tied together are 50 amps, not 50 + 50 = ! That 2 pole 100 amp CB can provide either 100 amps @ 240 volts or 200 amps @ 120 volts but in answer to your question as Chris stated it's 100 amps.

Does a sub panel need a main breaker?

Subpanel main breaker
A main breaker on a sub-panel is not necessary because this is in the same building (if you are in a different building then NEC 225.31, 225.32, 225.33 apply). That said, having a main breaker in the sub-panel is also acceptable.

What size breaker do I need for a sub panel?

Based on your question, since you will be having a subpanel, you want the breaker feeding the subpanel to be sized for the subpanel or slightly smaller. So if you purchase and install a 200A subpanel, then the breaker should be 200A. If you use a 125A subpanel, then use a 125A breaker.

Can you run a sub panel off a subpanel?


Yes, it's redundant, but it's still required. The wire feeding the new subpanel must be protected from overcurrent by an appropriately-sized breaker. If using both, 1 must be sized for the conductor, and the other can be that size or larger -- convenient if you buy a panel with a 100A breaker preinstalled.

What size aluminum wire do I need for 100 amp service?

Use 3 AWG copper or 1 AWG aluminium for the current carrying conductors.

What can a 100 amp service run?

100-amp service is generally large enough to power a small- to moderate-sized home's general branch circuits, plus one or two electric appliances, such as a range, water heater, or clothes dryer. This service may be sufficient for a home under 2,500 square feet if the heating appliances run on gas.