When it comes to wiring, wire size is a critical factor. Selecting the correct one ensures safety and complies with local codes.
The National Electrical Code requires you to use a certain wire gauge when transporting a 100 amp service. This helps preserve power quality over long distances.
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Copper Wire
When installing a 100 amp sub panel 200 feet away from the main service, it’s critical to select the proper wire size. Not doing so could lead to serious electrical issues and even fires if left unchecked. Fortunately, there are some guidelines you can follow for selecting an appropriate size for your project.
When selecting the proper size main breaker, the first step is to understand its maximum amperage rating. You can typically locate this information on either the main breaker itself or by checking with your electrical service panel.
Once you know this information, it’s easy to determine what type of wire you require. You have three choices: copper, aluminum or a combination.
For subpanel installation, you will require a wire with at least one hot, neutral and ground connection. Although you can choose a wire with multiple wires, this isn’t recommended as it could interfere with the function.
When selecting a larger wire, opt for one with a higher gauge to offset voltage loss that occurs over longer distances. This loss is known as voltage drop and can be measured using a voltage meter by taking readings at both ends – at your appliance or farthest device from the wire – and then comparing them to what appears on your circuit breaker.
For a 100 amp service, opt for 4-gauge wire or copper-clad wire with an AWG of #2/0. This wire has the best conductivity and can be used in numerous applications.
Another viable option is CCA wire, which combines steel’s high tensile strength and copper’s conductivity. This type of wire tends to be less costly than pure copper and finds applications in power supplies, motors, medical products, hardware, and magnetic assemblies.
Finally, you’ll require a ground wire for the subpanel. This should be 1-gauge and insulated with at least one layer of heat-resistant insulation to help prevent fires that could occur if there’s a short circuit in the wires.
Aluminum Wire
When installing a 100 amp sub panel that is 200 feet away, you must make sure the wire used can support the increased circuit amps. Southwire’s voltage drop calculator can help determine what size wire is necessary for your installation.
Copper wire is generally preferred to aluminum due to its lower tendency for overheating or corrosion and greater ability to handle longer distances. On the downside, aluminum is much cheaper and can be utilized in many applications.
Another advantage of aluminum is its flexibility and durability. It can be formed, bent and crimped into various shapes to suit the requirements for electrical installations. Furthermore, due to mechanical wear it’s much harder to break than copper does.
If you’re installing a new home and don’t have enough money to buy an abundance of copper wire, aluminum might be your ideal solution. In North America, copper is generally preferred for residential wiring projects; however, aluminum can still be utilized in certain instances.
In the 1960s and ’70s, aluminum wiring was often used in homes due to its cost-effectiveness compared to copper. It proved a popular choice for many consumers at that time.
Unfortunately, aluminum wire can present fire hazards if installed incorrectly or fails over time. These risks include deteriorated connections, poor insulation, overheating and fires caused by electrical shorts or overloads.
Aluminum wires often become overheated through excessive vibration when current passes through them. As this vibration occurs, aluminum vibrates more than copper does, leading to loose connections or damage to the wire itself.
Aluminum has a higher expansion/contraction coefficient than copper does when exposed to temperature changes, so any prolonged exposure can lead to corrosion and oxidation on the wires themselves. If left exposed, these connections could overheat where they connect to outlets, light fixtures or splices – potentially creating a fire hazard.
Due to this issue, it’s essential that your aluminum wiring is correctly installed when it comes time for a home inspection. Although this task may prove challenging for some homeowners, ensuring the wires are secure and won’t pose an unsafe threat to family or home is the best solution. Hiring an experienced electrician to perform this work for you is the ideal solution.
Conduit Size
When installing an electrical service, it is essential to use the proper wire size. Doing so can help avoid costly errors that could cause a fire or short circuit.
The size of an electrical wire depends on several factors, including local building codes. A licensed electrician can assist you in making the best choice for your requirements.
When selecting the size of your wire, voltage drop should be taken into account. As a wire gets longer, its resistance increases; to counteract this effect, use larger gauge wire.
There are various methods for achieving this, such as using special cable and adding insulation to protect against moisture and temperature changes. The National Electrical Code (NEC) suggests a voltage drop of no more than 3% for branch circuits and feeder cables to achieve optimal performance.
When selecting the ideal conduit for your installation, the size of your wire should be taken into account. Schedule 80 PVC is highly recommended as it can withstand high pressure, and in most areas, the conduit must be buried at least 24 inches deep.
Depending on where you live, underground conduit may be required or beneath a concrete slab or walk. Make sure to cover this with at least 50mm of concrete that extends down to rock so your electrical service complies with local code requirements. The NEC even provides an easy-to-follow table showing exactly how deep to bury different kinds of wires.
Voltage Drop
When wiring, there are several elements to take into account. One of them is voltage drop; this can be a major concern when running wires over long distances and lead to issues with motors, lights and appliances.
To avoid this issue, make sure you select the proper wire size. This is essential for safety reasons and will guarantee your electrical system runs efficiently.
A professional electrician will know the optimal wire size for your project. Additionally, they guarantee that the installation complies with all local wiring codes.
Copper and aluminum wire sizes are the two most popular wire types for this type of installation. Copper wires offer higher resistance, tensile strength, and expansion at high temperatures than their aluminum counterparts.
However, copper wires tend to be more costly than their aluminum counterparts and are subject to rust and breakage in high temperatures. On the other hand, aluminum wires offer cost savings and don’t corrode as quickly.
When selecting a wire, another factor to consider is its ampacity. The higher the ampacity rating, the better your home can handle electricity. With larger AMP services available, more electrical devices can run simultaneously.
As recommended by the National Electric Code (NEC), 200-amp aluminum or copper wire should have its total amps increased by 20% for every 100 feet away from a sub panel. Doing so helps avoid voltage loss over distance that could otherwise result in shortened motor and light lifespans.
With this rule, you can determine the ideal size of your sub panel wire. It depends on how far away it needs to run from your main panel and any voltage drops expected in that area.
For 100-amp service entrances, typically 2/0 gauge wire is used. This choice minimizes voltage drop over distance while being relatively inexpensive and simple to install.