What Size Grounding Wire For 100 Foot 20 Amp Service

If you lot want to install a 100 amp electrical service for a detached garage or a new room addition, you must use the proper gauge wire. To consummate the skilled work, yous'll need a allow. Check with your local building department to see if you can get the permit or whether yous'll require the assist of an electrician.

Installation of 100 amp electric service or subpanel needs a #4 AWG copper wire or #2 AWG aluminum or copper-clad wire inside a minimum one.25 inch, schedule 40 or eighty PVC electric conduit for cloak-and-dagger service. Wiring 100 amp service for a garage or room addition does require an electric allow and professional person installation past a qualified electrician following local electrical codes.

Homes today accept a 200 amp meter box connecting to the chief feeder breaker disconnect and so to a secondary panel (subpanel). A 100 amp secondary circuit breaker panel has individual circuit breakers bringing additional circuits to a designated area, like a garage, shop, shed, pool firm, or addition.

Size Wire for 100 Amp Service

AWG, American Wire Gauge, is the US standard for sizing electrical wiring.

Wiring a 100 amp breaker console requires either #4 copper wiring or #2 aluminum or copper-clad wiring. Which wire used is determined by the voltage drop and length of the wiring.

The following table reflects wiring size, length, and voltage drop:

Service or Feeder Rating	Copper Wire	Aluminum or Copper-Clad Aluminum Wire	Minimum Conduit Size
100 Amps	#four AWG	#two AWG	1.25 inch
110 Amps	#iii AWG	#one AWG	ane.25 inch
125 Amps	#2 AWG	#i/0 AWG	one.25 inch
150 Amps	#1 AWG	#2/0 AWG	ane.25 inch
175 Amps	#1/0 AWG	#iii/0 AWG	ane.five inch
200 Amps	#two/0 AWG	#4/0 AWG	1.v inch
225 Amps	#iii/0 AWG	250 kcmil	ane.five inch
250 Amps	#4/0 AWG	300 kcmil	2 inch
300 Amps	250 kcmil	350 kcmil	2.5 inch
350 Amps	350 kcmil	500 kcmil	three inch
400 Amps	400 kcmil	600 kcmil	3 inch

Source: National Electric Lawmaking

Many licensed electricians use #2 copper-clad or aluminum wire size. Because it has a lower conductivity than copper, aluminum wiring requires a larger diameter wire. You lot'll need a #2 judge wire for both aluminum and copper-clad aluminum wire.

To resist corrosion, the connexion terminals of aluminum wiring crave an antioxidant coating. At the connection terminals, copper-clad aluminum does not demand an antioxidant layer.

Aluminum wiring appeals to many since it is less expensive, lighter, and more flexible than copper. Even though copper is acknowledged to be a superior conductor, it is still cheaper, lighter, and more flexible than aluminum.

For copper wiring, you'll need a #4 AWG copper wire that is commonly used for electrical wiring since it is more oestrus resistant than aluminum. Copper doesn't rust and is unaffected by oxidation.

Why Copper Wiring is Preferred over Aluminum

Copper conductors are popular among electricians and homeowners akin for co-operative circuits. Copper wiring has several advantages, including:

Electrical conductivity: Copper wire is a highly conductive material, 2d only to silver. Copper can handle a greater electrical demand, so you lot may use a lower gauge wire. For the same level of conductivity, copper wire is around half the diameter of aluminum wire.
Estrus Resistant: Copper wire is more heat-resistant than aluminum wire since information technology has better rut conductive properties. The connections on the lugs stay tight due to the fact that copper wire does not aggrandize and contract like aluminum.
Corrosion Resistant: Copper is resistant to corrosion. The color of the outer surface of copper changes when it patinas. Oxidation causes patina, which does non affect conductivity.
Malleability: Copper wire is more malleable and conductive than aluminum wire. Considering copper is highly conductive, the wire strands are thinner, allowing for greater malleability without run a risk of breaking.
Distance: Copper may be used over greater distances owing to its highly conductive characteristics and heat tolerance.

Pros of Aluminum or Copper-Clad Aluminum Wire

Stranded aluminum or copper-clad wire is more popular on service entry cablevision for a variety of reasons, including:

Budget Friendly: Due to its lower cost, aluminum wiring is popular. Aluminum copper-clad wire is superior in terms of toll but less expensive than aluminum wiring. Aluminum wiring is a lot more than affordable than copper-clad and copper wires.
Installation is Quicker: Aluminum is lighter than copper and much more malleable in terms of wire gauge. Electricians enjoy working with it considering it is lightweight and readily passes through the electrical conduit, resulting in faster installation and lower material and labor costs.

When calculating wire size, you must know the length of the service line from the meter base to the electrical panel. The maximum voltage drop permitted is 3%, and we will discuss it in greater depth shortly. Choosing between aluminum or copper wire depends on how far your service entry wire needs to travel.

The Length Your Service Wire Runs Matters

When computing wire size, you lot must know the length of the service line from the meter base to the electrical panel. The maximum voltage driblet permitted is 3%, and nosotros volition discuss it in greater depth soon. Cull between aluminum or copper wire depending on how far your service entry wire needs to travel.

Depending on the location, distances may vary. Check with your local edifice section for regulations.

You can utilize aluminum or copper for a 100 amp service entry wire. The aluminum wire'due south reduced conductivity and rut resistance volition increase the judge. You can use copper wiring for greater distances.

What is Voltage Drop?

Voltage drop is the loss of voltage that occurs over the wire due to natural resistance.The greater the length of a wire, the more voltage is lost. Increase the wire approximate to first voltage loss.

The voltage at an individual circuit billow should be 120 volts. Using a voltage meter, take a reading at the appliance or the farthest device. Voltage drop shouldn't exceed iii% (117 volts on a 120-volt circuit or 233 volts on a 240-volt circuit).

How Many Wires You Need for 100 amp Service

Your electrical current load requirements determine the correct judge wire yous'll demand. The iii-wire cable run from the meter base of operations to the main disconnect box or main service panel consists of two hot wires and one neutral wire. Electric bonding joins the bars on the neural and footing confined.

The feeder cable is a iv-wire, comprising two hot feeder wires, one neutral wire, and one ground wire. You don't bond the neutral and ground confined in subpanels.

What Size Conduit You Need for 100 Amp Service

A 100 amp service will need a minimum of 1.25 inches, schedule 40 or 80 PVC grey electric conduit. You can use a larger conduit if necessary to maintain the inner fill of 40% or less. A 1.5 or 2-inch conduit is best if running three or more electrical wires within the same electric conduit.

In Affiliate 9, Tabular array 5A of the 2020 NEC, #ii Aluminum stranded insulated conductors take up 112.9mm² of fill infinite. If yous multiply 112.9mm^twopast three gives you a total of 338.7mm^two of fill space used by the entire feeder.

According to Chapter 9, Table 4 of the 2020 NEC, a 1.5″, Schedule 80 PVC conduit has 442mm² usable fill in rigid schedule lxxx PVC conduit.

For example, you may employ a 1.5-inch conduit or get larger if yous desire to pull the wires more easily. If two or more wires are nowadays, the surface area of the cables must not exceed 40% of the piping's internal volume.

You'll need to bury the conduit 24 inches deep in most areas. Some areas may require a deeper trench. A trenching tool like a ditch witch tin can speed the trenching process.

When choosing an electrical conduit, Schedule 80 PVC is thicker and tin can handle more than pressure than Schedule 40 PVC. The outer bore is the same for both pipes. Notwithstanding, considering Schedule 80 PVC is thicker, you'll have less inner fill space.

Check Local Electrical Codes & Permit Requirements

The National Electrical Code (NEC) is the authority for electrical codes, but they may differ by location. Using a licensed electrician familiar with your city'southward local rules and requirements, such as 100 amp electrical service, ensures that information technology meets them.

The 100 amp wire size mentioned in this post is from the NEC code and may differ from your local building lawmaking. The NEC standards periodically change or are enhanced to run into condom guidelines.

100 Amp Electrical Service Installation Costs

The cost of installing a 100 amp entry service in a home is virtually challenging to estimate. We must consider several variables, such equally the location of the installation and whether at that place are any additional services required.

Installing a 100 amp electrical service normally entails the post-obit elements: a 100 amp feeder wire, conduit, and a 100 amp sub panel.

Based on HomeAdvisor.com, the national average cost of acomplete 100 amp electrical installation costs $1500 to $four,500, with boilerplate costs of $3,000, includes the post-obit:

100 Amp Electric Console:Average price ranges from $500 to $1500, with a median cost of $1000.
100 Amp Feeder Wire:Average toll ranges from $thousand to $3,000, with a median price of $2,000.

Conclusion

Installing a 100 amp electric service or subpanel requires professional person installation by a qualified electrician. Installing a 100 amp subpanel needs a #4 AWG copper wire or #2 AWG aluminum or copper-clad power feeders inside a minimum i.25 inch, schedule 80 PVC conduit for underground service. It requires an electrician's professional installation post-obit local electrical codes.