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

The cable must have a wire gauge sufficient to the amperage of the subpanel—a 100-amp subpanel requires #4 copper wires or, more commonly, #2 aluminum wires, for example. (Aluminum is often used for feeder cables because the cost is typically much lower than that of copper wires.)

How do you hook up a 100-amp sub panel to a garage?





Quote from the video:
Quote from Youtube video: From so and here's where the 100 amp breaker goes and then we'll drop wire down run it all the way across in through there.

Does a garage sub panel need a 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.

Does a subpanel need a ground wire from main panel?

Most panels come with a bar joining the two, which is easily removed. Code requires subpanels to have a ground connection that’s independent of the main panel’s.

Can you feed a 100 amp sub panel with a 50 amp breaker?

Just wire it up. There is no problem using a sub panel that can take more current than you will ever feed it. Points to note: The cable to your hot tub will be rated for 50A (not 100A); therefore you must not upgrade the breaker in your main panel to 100A.

Can you feed a 100 amp sub panel with a 60 amp breaker?





You can feed a 100 Amp panel with a 60 Amp breaker. Keep in mind that the sub panel needs to be rated above the breaker size.

Can I run a 100 amp sub panel off 200 amp main?

Of course you can, you can add the 100 amp breaker to your 200 amp as long as it isn’t overloaded, to start adding the subpanel you must first calculate how many yards it will be from the main panel to the subpanel, there is a formula that calculates how much friction will be on the wire at the connecting distance, …

What size wire do I need to run a hundred amp service to my garage?

For 100 AMP service, you’ll need a #4 AWG copper wire or #2 AWG aluminum or copper-clad wire. Make sure to limit your voltage drop to 3% regardless of distance.

Can I running 100 amp service to garage?

A 100-amp subpanel in a detached garage may be enough to handle high-draw appliances such as refrigerators. As for basic lighting or low-load electronic devices, a 50- or 60-amp subpanel in a detached garage may suffice.

Should a subpanel have a ground rod?



Yes, any sub panel outside of the main building requires it’s own ground rod and a ground wire back to the main building. And yes, a sub panel in the same building as the main does not need a ground rod – only the ground wire.

How many grounding rods do I need for a sub panel?

You’d need at least one grounding electrode, or ground rod, for every sub-panel in a detached building. Whether you need two or not is determined by the soil and local regulations. So, check your local code requirements. Question: Do I need a permit to install a new subpanel?

Should sub panel be bonded?

Rule #3: In a subpanel, the terminal bar for the equipment ground (commonly known as a ground bus) should be bonded (electrically connected) to the enclosure. The reason for this rule is to provide a path to the service panel and the transformer in case of a ground fault to the subpanel enclosure.

Do you use a bonding screw on a subpanel?



Quote from the video:
Quote from Youtube video: But in this case. The bonding screw is that green headed screw right there. So that screw just simply threads through the neutral bus.

Why don’t you ground a subpanel?

With ground and neutral bonded, current can travel on both ground and neutral back to the main panel. If the load becomes unbalanced and ground and neutral are bonded, the current will flow through anything bonded to the sub-panel (enclosure, ground wire, piping, etc.) and back to the main panel. Obvious shock hazard!

Why does a subpanel need 4 wires?

The neutral and ground are not bonded in the subpanel. In this setup if a hot wire coming in contact with the non-current carrying parts of the electrical system, (outlet covers, panel covers etc), the 4th ground conductor will provide a low resistance patch back to the source tripping a breaker.

Can ground and neutral be on same bar in subpanel?

The answer is never. Grounds and neutrals should only be connected at the last point of disconnect. This would be at main panels only.

Do you need a neutral for sub panel?



All single phase 240 volt Sub-Panels MUST have a 4-wire cable feed which must have a separate insulated neutral wire and a separate ground wire, which may be uninsulated.

Can I tie the neutral and ground together?

No, the neutral and ground should never be wired together. This is wrong, and potentially dangerous. When you plug in something in the outlet, the neutral will be live, as it closes the circuit. If the ground is wired to the neutral, the ground of the applicance will also be live.

What happens if neutral wire touches ground?

In Short if neutral wire touches a earth wire,



An earth wire carrying load current is a risk of electric shock because a person touching this earth may present an alternative path for the load current and thus the risk of electric shock.

Where do you bond ground and neutral?

Neutral wires are usually connected at a neutral bus within panelboards or switchboards, and are “bonded” to earth ground at either the electrical service entrance, or at transformers within the system.