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What is the Correct 70 Amp Wire Size [Confusions Clarified!]

It’s very crucial to know which size of wire to choose for your electronic equipment. If you’re struggling with that too, you’ve come to the right place! Here, I’ve clarified some basic things that you need to know about it.

What would be the correct 70 amp wire size?

Firstly, the wire size depends on the amperage, or how much electricity the equipment is drawing. Secondly, it should be able to carry overload until the breaker operates. We can say that the wire size needs to be correct. And it can carry the load but not so long that it never trips. 

Alongside this information, you also need to read the whole article to get accurate ideas. I have tried to cover everything you’ll be needing!

Then what’s stopping you? Read on!

Why is Picking The Right Size Important

If you use the wrong one, your circuit will probably end up burning. To avoid this kind of scenario, you should be aware of the proper wire size. 

Unfortunately, most people are ignorant about the fact that their choices have an impact. People frequently make connections without consulting or summoning a certified electrician. When you do it incorrectly, catastrophe follows.

When using a circuit breaker, you need to take extra measures. Installing the proper components will considerably reduce the likelihood of frequent problems occurring. 

In most cases, problems develop as a result of inaccurate components. The various electrical components must always be compatible with one another.

The level of amperage and the length of the wire are utilized to determine the wire size.

The narrower the wire diameter, the greater the resistance to the flow of energy. If a wire that is too small is employed, it may melt. 

And also set fire to the house. It could happen due to too much current being drawn via that too-small wire. That’s why the voltage drop calculator needs special attention.

The friction from the higher resistance generates this considerable amount of heat.

But, what happens if I choose an oversized one?

If you utilize a wire with an extremely big diameter, you’re probably squandering money on unnecessary metal. It entails a waste of money and fetters efficiency.

What is The Right Wire Size or 70 Amp Circuit Breaker

Based on the circuit breaker rating, minimum wire size is necessary. You may acquire this amount by entering the breaker amperage. And a wire length of one foot into a good voltage drop calculator. 

Several factors influence the selection of wire. The gauge of a wire is a measurement of its diameter. The standardized system for this measurement is AWG (American Wire Gauge). 

Wire gauge is measured from highest to lowest number, with higher numbers indicating smaller wire size.

It is critical to choose the correct wire size for circuit breakers. Because it determines how much electrical current can pass through it. Also the amount of resistance it creates. For example, 30 amp wire size is different from 70 amp.

The chart below will tell you about the wire sizes required for different amperages:


Hopefully, now you understand the different wire sizes for different amps.

Here I have mentioned some quality circuit breakers for you:

Product 1
Product 2

These circuit breakers work for any device, be it for your 40-gallon electric water heater!

The appropriate wire for 70 amp is either gauge 4 aluminum or gauge 6 copper. That is, assuming no other factors are influencing the performance.

This is determined by whether aluminum or copper is utilized or not. The ambient temperature is also taken into consideration. 

At an ambient temperature of 140°F or 60°C, you can utilize 6-gauge copper for a circuit breaker with this rating.

Hopefully, now you’ll be able to pick the right size.

What are The Consequences of Picking The Wrong Size

People have a grave misconception about wires. They think that if the ends of the wire fit into a connection, it’s all good. Circuit breakers don’t fall in this category.

Smaller diameter ones are less expensive than larger ones. Unaware people frequently opt for the cheapest option. They often assume that it will make no difference. 

Unfortunately, it will just cost them more money in the long term. But if you already have a wrong-sized wire, these could be the probable outcomes:

Degradation of Performance

Peak efficiency may be impossible to achieve if appliances are connected using smaller wire. The appliances cannot receive enough energy needed to function at their peak. 

As a result, your appliances are unlikely to work optimally.

Initiate A Fire

The worst-case scenario is a fire started by a burning electrical component. Although modern circuit breakers include safety features, they’re not sufficient for excessive load.

When the circuit breaker detects an overload, it will trip. It will prevent current from flowing through it. It aids in the prevention of harm. 

Having a trip mechanism, however, does not completely prevent a fire from occurring. People are often confused about what tripped the breaker in the first place. 

Bust The Equipment

Aside from the performance concerns and the risk of starting a fire, utilizing a smaller one may cause harm to your equipment. When the power supply is unstable, it might cause your equipment to malfunction.

Hopefully, now you understand what happens if you pick the wrong size for your wire.


Question: Can you have 100 circuits on a 70 amp panel?

Answer: You can run 100 circuits with each of them attached to a device that pulls 70 amps. But only 1 of those devices can remain operational at a time. However, you may use 70 circuits where each of them pulls 1 amp load and runs them simultaneously.

Question: Can using an undersized breaker cause problems?

Answer: A breaker serves as a distribution hub for electricity, distributing it across your home. Power-hungry devices overload the circuit, causing a power outage. Flickering lights and tripped circuit breakers are typical issues of an undersized power system.

Question: What happens with an oversized breaker?

Answer: An oversized circuit breaker can be hazardous. A breaker will trip if there is a direct short in an appliance, even if it is oversized. But it may not trip with a crossed or burned wire. This could result in a shock hazard. 

Final Words

I really hope that all your confusion regarding the 70 amp wire size has been clarified. Size doesn’t matter in a lot of things, but in this case, it definitely does!

Always remember to wear rubber footwear when working with electronics.

I’ll see you in another article again. Till then, sayonara!