It’s a limit on the total, simultaneous load that the breaker will support. If you’re currently using 150A of power in your main panel, turning anything on from the subpanel will likely trip it the main. However, the odds of you ever using 150a at your main are slim, as are the odds of using 100a at the sub.

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, …

Can I use a 125 amp panel with 100 amp service?





If it’s a 125 amp panel, then you can use a 100A breaker on the main panel to feed the breaker. The new sub panel must always have the same ampacity rating as the panel that is feeding it.

How many amps can a 150 amp panel handle?

200 amps

If you can put in a tandem breaker, this increases the panel’s acceptance for more circuits. But take note, a stab or a bus bar finger in a 150A panel shouldn’t exceed more than 200 amps.

Can you run a 200 amp sub panel off 200 amp main?

Is feeding a 200A sub from a 200A main legit? Yes, and you don’t even need another 200A breaker. The 200A breaker alread present in the panel will suffice, and so you can use a subfeed lug kit as DrSparks advises.

Can you run a 100 amp sub panel off a 100 amp main panel?





Let me try and answer some of your questions. First the panels you are looking at that are rated 100A simply means you can use them for any application up to 100A. You can for example add a 60A breaker to your existing panel and protect the new subpanel with a 100A rating.

How much load can a 100 amp panel handle?

In other words, a 100-amp electrical service should be expected to provide no more than 19,200 watts of power load at any given time.

What size wire do I need to run 100 Amp Service 150 feet?

2/0 AWG wire

Wire Size For 100 Amp Sub Panel 150 Feet Away
100 amp service 150 feet away from the sub panel requires #00 AWG wire (also known as 2/0 AWG wire). This wire has a median ampacity of 175 amps; more than enough than the required minimum 162.5 ampacity.

What size wire do I need to run a 125 amp sub panel?



125A is #1 copper or #1/0 aluminum (you need to call it 120A feeder, but you get to round up to 125A breaker since 120A is not made.) If you need full declared 125A you’d need 2/0 aluminum.

What size should the service drop wire be for a 100 to 125 amp service?

For a 100 amp service, you will need a 1-gauge wire. For 125 amps, you will need a 1-gauge copper wire.

Can I run a sub panel off a sub panel?

Answer: Yes. The main electrical service panel is where branch circuits originate. A branch circuit consists of the circuit conductors between the final over-current device protecting the circuit and the lights, receptacles and equipment supplied by the branch circuit.

How do I know if my electrical panel is overloaded?



Buzzing or Sparking If you hear a buzzing sound or see sparks near the service panel, this indicates a major electrical problem. Overloaded circuits can damage breakers, connections and wiring, leading to arcing that creates sparks or buzzing noises, as well as a very serious risk of fire.

How many subpanels can a house have?

Even though there is no limit on the number of subpanels that you can add to a circuit, it shouldn’t exceed 160 amps when you’re using a 200 amp main panel. Always follow this guide to install subpanels effectively.

How far can subpanel be from main panel?

The right feet would be between 4.5 to 5 feet.

The cable running from your main panel to the subpanel depends on the amperage rating. For instance, for a 30A panel, use a 10 AWG, three-wire conductor.

Can I add 100 amp subpanel?



If you have older 60-amp or 100-amp main service, it is entirely possible that you will need a service upgrade to 150-amps or 200-amps before you are able to adequately power a new subpanel.

What size wire do I need to run a 100-amp service 200 feet?

To feed a 100 ampere secondary panel 200 ft. from the main panel, you’ll want to use 1 AWG copper or 2/0 aluminum conductors. This is large enough to safely carry 100 amperes, and to maintain power quality over the distance.

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

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).