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What Size Wire Do I Need for 600 Amps? (Explained)

The electrical service that will be mainly delivered to your house would be from the electrical utility company is the total available capacity which will always get measured in amps or amperes.

Usually, the houses we generally see can have an electrical service between 100 to 200 amps. This is the measurement called amperage, which is not always accurate and can vary between 30 amps.

If we know the size of a house’s electrical service then we will be able to help you decide if you need an upgrade to the electrical service or a change of wires because of their incorrect size.

Yes, wire size matters a lot due to their particular job of transferring electrical currents through them. Having the wrong size of wires can affect a household’s electronics.

In worst-case scenarios, there can be accidents of fire in the homestead because of the wire size.

Therefore, keep reading below to know more about the amount of amperage a household can handle and also the designated wire sizes for the total amperage coming out of the amp service of the house.

What size wire do I need for 600 amps?

We must follow certain rules when it comes to electrical works. For example, if were to have a 100-amp service we would need a 1-gauge wire. If it were a 200-amp service, we would need 250kcmil- gauge copper wire, and for 600 amps we would need 1500 kcmil-gauge wire.

When working with electronics, there are many precautions a person needs to have whether they are a beginner or a professional.

Sometimes the weight of the situation can outweigh that of one’s life and someone might lose their life due to small mistakes while working on electrical devices.

Thus, even the simplest wire size is important to pick that is compatible with your equipment only. If you are in a hurry then there are some designated guides on the net that will show you what size to buy.

Even if you want to buy a circuit breaker or sub-panel there are plenty of guides to follow. If you are someone who is switching from 200-amp or 400-amp service to 600-amp service, then you need not look anywhere else.

Because we are going to discuss below the required wire size and the power delivery of a 600-amp service below. We have gone through multiple products by following the recommended NEC’s chart to ensure utmost safety. Keep reading below as we discuss the different 600-amp services.

600-amp single-phase service:

This particular service will require two 350 kcmil copper wires per phase. That would be sufficient per the NEC in most of the cases.

A single conductor 600A usually needs a 1250 kcmil (basically 595 amps) or a 1500 kcmil (in other words 625 amps) to get 600 amps. This is a special case where the service termination requires 75C-rated wires.

600-amp 3 phase service:

In this case, we would need to use 300 copper or parallel 400 Aluminum in 2-12” EMT, 3” EMT if it becomes a long run. We would also reduce the neutral if it is not a delta system.

The ground wire for 600-amp service:

When it comes to the ground wire, we will need 1-kcmil gauge wire of copper wire and Aluminum 2/0-kcmil wires.

Aluminum wire for 600-amp service:

Now the size of aluminum wire for 600-amp service is 2000 kcmil.

Copper wire for 600-amp service:

In this case, we always need to follow a rule of thumb.

That is if we have a 70-amp circuit breaker we would need 4-gauge copper wire, if it is 80-amp, we would need a 4-gauge copper wire. Then if we have a 100-amp service we will need 1-gauge wire.

When it comes to the wire for the 600-amp breaker we would need 1500 kcmil gauge wire, because for the 200-amp service we would need 250 kcmil-gauge copper wire.

What happens when you choose the wrong wire for 600 amps service?

If we happen to use the wrong wire for the 600-amps service, then a series of things might happen. In short, if the wire’s too large then it will be fine. If the wire is too small then the wire will burn.

Some might think it’s rather a useless question to ask. However, we understand a person could be in any kind of situation and buy the wrong size. Thus, let us go into detail and talk about why you need to stick to the right sizes for the wires.

Thicker Wires:

Usually nothing will happen for the 600-amps service. In the worst possible case, you will just spend more money than you needed to spend.

A good scenario would be that your wires would be ready for a power upgrade. For example, if you took a branch and designed it to be 16A compliant but then after a while decided it needs to support 20A, then the wires you might have installed will already be 30A compliant.

Slightly Thinner Wires:

The wires will overheat and may cause a house fire. The housefire will leave you with no insurance company that will pay a penny.

Furthermore, they will sue you rather if you go on to ask for money from them claiming you are a fraud.

Very Thin Wires:

These wires will surely go to the point where they will burst and maybe you would think that would be the end of it and you are safe.

However, you will be very wrong about that and that’s because somebody from the grid company later will arrive at your house and ask you why’s your house the main reason for the shutdown of the whole neighborhood.

How much does it cost to upgrade to a 600-amp service?

The cost to upgrade to a 600-amp service commercially as a service is around the $12000-$15000 range. That is definitely a lot more expensive than the other amp service upgrade.

If the conductors have to be larger to support the increased ampacity, so the larger the conductor, the more copper or sometimes aluminum, meaning more money is involved. The service entrance panel has to be rated for 600-amp service.

There are houses that are generally very old and thus when they are restored, they might sometimes need more than 400-amp service and in some cases even more than that.

However, that is a rare case, but the size of the wire always changes and is not compatible with the amount of rated amp service.

When we go from 200-amp or 400-amp service to 600-amp service which is much more involved. We are talking about going from a branch circuit panel to a distribution panel. Therefore, the equipment involved in this venture will also be much more expensive.

What is the largest amp service to a house?

The general electrical service of a house can be anywhere between 100 to 200 amps. Most houses of medium size do not have anything more than 200-250 amps of amp service.

Amperage is the measurement of the volume of electricity that flows through the wires. However, this measurement is not completely hundred percent accurate. The measurement can vary between 30 amps in some of the old homes.

There are records of these homes of very old age which are usually vastly larger than the usual homes, and use extensive electric heating systems and other electrical equipment that require the amp service to be as high as 400 amps.

Therefore, the largest amp service to a house can be in the 400 amps range. After that point, things can start to get absurd if the scale were to increase even more. Because of the absurd power demand that the house would need.

This, however, is not a normal case where we would find homes that need more than 400-amp service to function properly. Therefore, the wire size remains the same for almost all the houses in general.

Furthermore, we should always be aware of the wire sizes from being too small for the required size. As that would in evidently lead to a serious accident of sorts.

Final thoughts

The 600-amp service will also need 1500 kcmil-gauge wire to it. It will also need two ground rods. If the wire size is bigger than that amount then there will be no harm done. However, if the wire size is even slightly smaller than 1500 kcmil-gauge then there will be fire due to overheating.