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What Size Conduit for 6/3 Wire? (Explained)

The conduit for an electrical wire is basically a tube system that is used to distribute and safeguard wires and cables inside a building. It is a very important element to properly route the wires within a particular structure.

A 6/3 wire is one of the most commonly used wires for appliances, lighting, and pieces of machinery. So, you might be wondering what size conduit will be perfect for a 6/3 wire. Let’s take a look at what size conduit you will need for 6/3 wire.

Conduit size for 6/3 wire

A conduit of size 2 inches will be good enough to distribute a 6/3 wire across a building. It will provide you the required space and flexibility to route and protect the 6/3 wires without any issues. You should use PVC conduit for this wire as it will keep it safe from water damage.

A 6 AWG cord with 101 strands of three-stranded bare copper conductors is known as a 6/3 cable. It is used mostly to power up pieces of machinery, lights, and appliances.

This wire needs to be distributed through a conduit to ensure proper electricity flow and also to prevent any damage.

Getting a conduit of the right size is very important for the 6/3 wire. This is due to the fact that this wire can get damaged comparatively faster than other types of wire.

If water remains in contact with this wire for a long period of time, the wire will get damaged permanently.

There are a few types of conduit available on the market. A couple of conduits are engineered in such a way that they will prevent water from entering the conduit and protect the wires.

There are mainly three types of conduit. They are PVC conduit, rigid conduit, and emt conduit. Let’s take a look at what size of PVC, rigid, and emt conduit you will need for the 6/3 wire.

PVC conduit:

A two inch PVC conduit is good enough to pass a 6/3 wire. You can distribute almost 26 6/3 wires using a 2 inch conduit. If you need to route more than 26 6/3 wires, you can go for PVC conduits that have a size up to 4 inches.

The PVC conduit traps the heat that is released from the wire and also the external heat. The wires might overheat since they can’t breathe. The heat can damage the wire even if it isn’t hot enough to ignite a fire, which is a hassle.

Rigid conduit:

You can use a 2 inch conduit to distribute the 6/3 wire across a house. The rigid conduit is one of the best conduits available on the market, as it will last for a long period of time.

While passing multiple 6/3 wires through a rigid conduit, you should keep in mind that heat is generated when electricity flows through the wires. This heat can damage both the conduit and the wires.

Emt conduit:

An emt conduit of 2 inches will be perfect to route the 6/3 wires within a building. You can distribute around 26 6 AWG cords, that is 6/3 wires within a fixed space.

How many #6/3 wires can go in a 3/4 conduit?

A 6/3 wire is basically a 6 AWG cable. In a ¾ inch conduit, four 6/3 wires, that is, four 6 AWG cables can pass through. You can quite easily distribute four 6/3 wires through a building without any issue.

However, while passing multiple 6/3 wires across a 3⁄4 conduit, you should be very cautious. This is due to the fact that when electricity passes through wires, heat is formed.

This heat can accumulate inside the conduit, which will overheat it and it will eventually damage the wires.

Although you can pass four 6/3 wires through a ¾ conduit, you should use less than four wires on the conduit to prevent any damage. In fact, if the conduit is made of PVC, you should definitely use less than 4 wires since PVC conduit traps heat.

3 factors that affect conduit size for 6/3 wire

There are numerous factors that affect the conduit size for 6/3 wire. Knowing the factors is very important to get the conduit of the right size.

If the size of the conduit for the 6/3 wires is not perfect, you might risk damaging the wires and eventually causing a problem in the building’s electrical system.

Number of 6/3 wires:

The number of 6/3 wires you want to pass through a conduit is one of the most crucial factors that affects the conduit size. A 2 inch conduit size can accommodate around 26 6/3 wires.

If you need to pass more than 26 wires through a conduit, you will have to get a larger sized conduit. The higher the number of 6/3 wires you want to distribute, the larger the size of the conduit will be.

The breadth of the 6/3 wires:

The breadth of the wire is also one of the most common factors that affect the conduit size. The breadth of the 6/3 wire can vary from unit to unit due to the coating of the wires.

If the coating of the wire is very wide and strong, the breadth of the unit will be higher. You will need a larger sized conduit if the breadth of your wire is more.

Coating of the 6/3 wire:

If the coating of the 6/3 wire is not very strong, you will need a conduit that offers waterproofing. The conduits that offer water proofing are of a larger size than usual.

How to determine conduit size?

Determining the conduit size is not as complicated as it may seem. You can determine the conduit size quite easily in a matter of minutes.

You will however have to do it in the right way if you want to distribute the wires perfectly throughout the building. Let’s take a look at how you can determine the conduit size.

Open chapter 9 of the NEC book:

Depending on the type of the wire and conduit, you will need to select the fill table. You will have to check the first column to get the wire gauge. Beside it, you will find how many wires you can put in a particular conduit.

You should always select a number greater than the number of wires you will have to put inside the conduit.

Calculate the total diameter of the wire:

After selecting the number of wires in the NEC book, you will have to calculate the total diameter of the wire. You can use a meter gauge to calculate the diameter of the wires.

You can also find the diameter of a particular wire in table 5 of the NEC book. Multiply the diameter of the wire and the number of wires and add all of them.

Find the size of the conduit:

From table 4 of chapter 9 in the NEC book, find the type of the conduit you would like to use.

Read out the permitted load for the size and type of conduit given in the table. Select the load that is more than or equal to the calculated fill in the previous step.

How do you pull a 6/3 wire through conduit?

Pulling a 6/3 wire through a conduit is not quite difficult, but it has to be done in the right way to prevent any damage. However, most people refrain from using conduit as they seem quite inconvenient to install.

You can quite simply pull a 6/3 wire through a conduit in a matter of minutes. One of the easiest ways to do so is by tying a string to the wire and pulling it from the other side of the conduit.

You can also bring in a vacuum hose to pull the 6/3 wire through the conduit.

You can also push the 6/3 wires through the conduit to pass it through the conduit within the building. You should tape all the wires together before pushing them to make the process easier.

Final Thoughts

A 2 inch conduit will be perfect to distribute multiple 6/3 wires within a house or an office. You can pass up to 26 6/3 wires through any conduit of size 2 inch. However, if you have to pass more than 26 6/3 wires across a building or a fixed space, you will have to get a larger sized conduit.