This video shows what size wire to buy when installing or upgrading an electric service panel. Depending on the wire’s length and the temperature rating, you will need around a 3-gauge copper wire to power a 100-amp subpanel. Often, the result is not a common circuit breaker size. Aluminum wires are rated differently than copper wires. Underground wire for a residential circuit usually is installed with underground feeder (UF) cable, which is rated for outdoor use and direct burial. 2) At your main electrical panel you could install a couple of feet of 6 AWG stranded copper or 4 AWG stranded AL for the 50 amp breaker. I plan on purchasing a newer MH in the future so I want to install a 50 amp receptacle. Shipping & Returns Steve needed to run 50 amp service from his main panel in his home to a 100 amp breaker box (shown below) in his new shop. Select wire size: Select conductor type: Choose maximum voltage drop (%): Calculate Reset. Some jurisdictions may still consider this as a 'feeder', which would only require a #2 (aluminum), as cbjack referred to. Are you using a 100 amp main breaker service panel as a sub… As an example, for a 120-volt circuit, you can run up to 50 feet of 14 AWG cable without exceeding 3 percent voltage drop. 4 is bigger in size than No. These days, the only aluminum used in most new residential projects is in the service entrance cables from the utility, although you may see aluminum show up on voltage drop tables. If you are 60 feet away and you use copper wire you will need 180 feet of copper wire and a ground wire of at least # 10 wire all copper. For example No. However, I recommend a 100 amp panel. Ground size for 100 amp sub panel 200ft away. Call 855-880-8010 If you are installing a 60 amp sub-panel 400 feet away from the main service panel then use AWG # 4. This can lead to decreased performance, unnecessary wear, and even premature failure of electrical equipment. In other words, if you put too many loads on one circuit and exceed the standard 80 percent safe capacity (1,440 volts for 15-amp circuits; 1,920 volts for 20-amp circuits), you'll add unnecessary voltage drop. Learn What Happens When an Electrical Circuit Overloads, The Basics of 240/250-Volt Air Conditioner Circuits, How to Repair a Wall-Mounted Electric Heater, How to Wire a Line-Voltage Thermostat for a Baseboard Heater, Safety Rules for Using a Portable Generator, Calculating Electrical Load Capacity for a Home, What You Need to Know About Kitchen Electrical Code. UPDATE: Since it will be going underground and will be entirely in conduit, I'd recommend type XHHW wire. All conductors of electricity, including wires, impose some resistance to the flow of electricity. EMAIL SPECIALS the cost of wire. Many of our customers here at Wire & Cable Your Way are looking for electrical wire to service their new backyard woodshop, like this one shown above. Either of wire sizes are rated for a 50 amp feeder breaker. Can't find what you're looking for? 2. About Us The following are the maximum lengths of cable you can use while still maintaining a 3 percent voltage drop for the given wire size (AWG) and circuit voltage. If you have any questions please feel free to give us a call at 855-880-8010 or send an email through our support page. Fed with a 50 amp breaker. I have a sub panel in the basement that has 100 amp service its 60’ from the meter. Now the feeder breaker can't be any larger than then SMALLEST of the ratings of the feeder wires or the sub-panel. As an example, for a 120-volt circuit, you can run up to 50 feet of 14 AWG cable without exceeding 3 percent voltage drop. Steve needed to run 50 amp service from his main panel in his home to a 100 amp breaker box (shown below) in his new shop. The solution is simple: Keep the total load on the circuit to 80 percent or less of total capacity. Below are the best selling wires our customers use for service to a 100 amp sub-panel – all available by the foot at our store WireAndCableYourWay.com. So can I run a bigger wire for the first 50 feet then go down a size for the last 100 feet. Timothy Thiele is an electrician who advises residential DIYers on how to make home installation projects safe and easy. Need Help? I'm trying to find out what size wire i will need to run a sub panel out to a new shop I am building on my land. If using the 4 AWG Aluminum, make sure the 50 amp breaker is rated for AL wiring. 100 yards = 300 foot. If installing aluminum conductors, the feeder circuit needs to be 1 AWG aluminum and this results in a voltage drop of 2.7% or a loss of 3.2 volts. When it comes to underground wire, the longer the wire, the greater the voltage drop. Your email address will not be published. This is a good goal to shoot for when sizing the conductors for an underground cable. Burial distance will be 18". 125 feet underground to 100 amp sub panel. Seems like it would save some material cost. At 40 amps actual you'd be at 3.1% very close to the recommended 3%. Wire size is another factor: Smaller-diameter wires have more resistance than larger-diameter wires. I am thinking about running 40 amp service to a barn. For example, if the load calculation comes out to 48 amps, you should use a 50-amp breaker to protect the circuit. Steve purchased our 6 AWG THHN/THWN Copper Building Wire for his project. ... what size wire do I need to use to run 60 Amp service to a sub-panel 50 -60 ft. from the main panel? Run the conduit from the garage to the main panel box. 6 is only good up to 40-amp. #3 THHN/THWN-2 Wire for 100 Amp Sub-Panel. COPPER. The typical rule of thumb that techs will usually go by is that when you have a 30 amp circuit breaker, 10-gauge wire is the right size to go with. Wire size for a 100 amp sub panel 200 feet away The garage is about 200 feet from my house and it has a 2 inch pvc stubbed out underground. Excessive voltage drop means that motors, appliances, and other devices don't run as fast or efficiently as they are designed to. My loads will be significantly less than that to run various tools individually, as well as a compressor and vacuum. The next logical size is 250MCM which will go 383 foot. Feeder circuits supplying subpanels are 240-volt and require a … Save my name, email, and website in this browser for the next time I comment. Result: 1 conductors per phase utilizing a #3/0 Aluminum conductor will limit the voltage drop to 2.82% or less when supplying 100.0 amps for 250 feet on a 240 volt system. Note: Comments to this blog are moderated. and you can simply round up to the next higher size of the breaker. This is a five percent table which means at these amperage ratings at the listed distances, 5% of the power would be lost to resistance. Get daily tips and tricks for making your best home. First of all, may I assume that you want to run a 2-pole (240V) 100A feed?.. 100 amp 20 slot pannels are common and cheap. Any comments promoting other products or web sites will be deleted. For a 50-amp aluminum wire, use No.4 AWG. Sizing the wires, or conductors, for an underground cable is no different than sizing for other household circuits and is typically based on the total load, or electrical demand, of the devices on the circuit. Wire size for a 100 amp sub panel 200 feet away [ 8 Answers ] I have a 200 amp main panel in my house and I just built a garage and am planning on putting a 100 amp sub panel in the garage. Need Multiple Cuts of Electrical Wire & Cable by the Foot. Special Orders. I'd guess though actual load probably wouldn't even reach 50 amps. 2) For a 100 amp/120/208 volt at a distance of 150 feet, the voltage drop is exactly 3% if using 3 AWG copper conductors or a loss of 3.6 volts. I am wondering what size aluminum I would need to feed it, and if I can use a smaller pvc. 1.) The well is only used in the summer to water lawn. The following are the maximum lengths of cable you can use while still maintaining a 3 percent voltage drop for the given wire size (AWG) and circuit voltage. From there I ran 3 # 6 copper wire another 125’ to another sub panel at my well. Frequently Asked Questions this gives you the opportunity to run two 120v circuits off two different breakers from your main panel to the shop. Privacy Policy, CUSTOMER SERVICE Voltage drop occurs in any wire run, but it is rarely a problem with indoor wiring, where the distance from the circuit breaker panel to the end of the circuit is usually relatively short. The National Electrical Code (NEC) recommends a maximum voltage drop of 3 percent for individual household circuits (known as branch circuits). However, if the cable run is long, as underground runs often are, you may need to increase the wire size to account for voltage dropâa loss of voltage in the circuit caused by the natural resistance in the wires. So I would use a 60 amp breaker and feeders, but with the 100 amp sub-panel. Sign up to receive special offers and 5% OFF your next order! Select the type conductor wire material, the circuit voltage and the phase of the circuit. Order Support Voltage drop increases as the load on a circuit increases, and overloading a circuit contributes to excessive voltage drop.  Steve purchased our 6 AWG THHN/THWN Copper Building Wire for his project. This condition is assumed in many voltage drop calculations and tables. Five percent is normally acceptable in low voltage systems, but if you want a 2% figure, divide the given distances by 2.5. No. Someone stated the 100 amp panel won't take the wire size… Source: NFPA 70, National Electrical Code, Chapter 9, Table 8. The sub panel will be app. Do I have to buy all 3 wires (2 hot and 1 neutral) the same size? In addition to the three #4 you will need a #8 for ground. Commonly available 60 amp panels are usually limited to 8 or more slots. A sample of 120 volts, single phase, copper wire, 144 feet (one half of a 288 foot circuit) with 10 amps load on it yields a number 10 awg wire size. Enter the total amperage on the circuit; also enter one half of the total length of the circuit. CONTACT Grounding a Sub Panel at a Detached Building Electrical Question #1: Do I need to run a ground wire for a 200 amp sub panel that is 200 feet away from the main panel? Steve buried the 6 AWG THHN copper stranded wire inside a conduit which can be seen below: We greatly appreciate the photos, Steve, and glad everything worked out for you! The distance to the sub-panel is 95 feet from the main box and I would like to know what size wire would be sufficient for 220v 50 amps at 95 feet, also indoors. Required fields are marked *. “I put in a 100A box in the new shop, but am only feeding it from a 50A breaker in the main panel from the house service. Voltage drop is also a waste of electricity because the energy is lost as heat rather than being available for use by the circuit devices. Panel Options for a 50 AMP Hot Tub 220 Volt Circuit Electrical Question: Hello Dave, I am installing a hot tub that calls for 50AMP service. If you take another measurement of the circuit at the farthest device from the panel and get a reading of 114 voltsâa difference of 6 voltsâthat circuit has a 5 percent voltage drop (5 percent of 120 = 6). Copper wire has lower resistance than aluminum wire, but chances are good that you'll be using copper in any case. Looking for the right size wire for your 100 amp sub-panel for a detached building, garage, or shed? Only comments relevant to our readers will be posted. What size copper wire should I use for 70 feet and 30amps? This is known as voltage drop and is represented as a percentage of the total voltage supplied at the power source of the circuit. This means that for a 100 amp sub-panel, you need to have # 1/0 wire (aluminum). What wire size for 100 Amp sub panel 100ft in length form 200 Amp main panel? If this were my shop, and I needed 60a service at 100 feet, I would likely run 8 gauge wire, 8–3w/ground. I whant a 60 amp subpanel coming from a 100 amp service whats the allowable volt drop ? ... Wire size. Its 85 feet from breaker to receptacle and 25 feet to motorhome. Paige Wire Size Calculator example calculating SEC wire size Our customer Steve, a skilled project engineer sent in these pics from a home project he recently completed. 15 ft. from the main panel. The garage is about 200 feet from my house and it has a 2 inch pvc stubbed out underground. I Whant to install a sub panel in a garage thats detached from a house 75 feet away . The smaller the number on the wire, the larger the wire diameter. Depends on the size of the sub-panel in that garage. Topic: Wire size for 100 amp subpanel: Member Name: L West Email: leon_west@porex.com Location: Georgia Title: Not_Listed In Trade Since: 0 Registered: May 2001 Total Posts: 5. posted May 07, 2001 at 11:50 AM I'm installing a 100 amp sub-panel in my basement. Such an installation is typical when running a circuit to an outdoor location, such as a garage, shed or other outbuilding, or to a yard light or water feature. Per the I.A.E.A table 4/0 copper will go 323 foot before the voltage drops 3% from your nominal. Introducing "One Thing": A New Video Series. also do i have to run it in conduit undergrond and whats the hight when i come up in the house is there a code that says how high i can run it up the side of the house. I need to install a sub-panel in a shed. At the main panel, use either of this size. What Gauge AWG Wire to Use for Solar Electric Systems. Assuming the voltage is 240 volts, the wire size for a 100 amp panel at the end of 400 feet and holding the voltage drop to 3 %, the wire will be 3/0 in size. For a 40 amp you need a 8-gauge wire size and for a 20 amp, you will need a 12-gauge wire size. Use 1 1/4-inch PVC conduit for a 100-amp sub panel or 1-inch PVC conduit if the sub panel is 50 amps or less. We cut 6 gauge THHN by the foot and offer it in several different colors at a great price! Also I am going to put the garage sub-panel on its own 50 amp breaker. I have 2 20amp double breakers at the well. Data from the Gould Shawmut Book of electrical information. 0. or Contact Us », COMPANY INFO Total run distance from main panel to sub-panel is 80 ft and includes three 90 degree turns. My question is about Grounding a Sub-Panel: I am installing a 200 amp sub panel to an existing structure that is 200 plus feet away from the main panel. Sub panel at well is grounded to well casing. Whatâs the Difference Between SOOW, SEOOW, and STOW Portable Cord? Aluminum wires come in different types. Unfortunately the main panel is not very accessible to run new wiring so I would like to run the 6-3 from my sub panel to the hot tub disconnect. Outdoor circuits, however, are often quite long and the voltage drop can be significant. Your email address will not be published. My home has a 100 AMP sub panel feeding off the main. If you measure the voltage of a circuit at the service panel (breaker box), you should get a reading of around 120 volts (for a standard circuit). Dig an 18-inch deep trench for the outdoor electrical wire, which you will run from the main panel box to the garage sub panel. Since voltage drop is caused by the resistance of conductors, the more conductors you have, the greater the voltage drop. Please call us: Copyright © 2019 Wire and Cable Your Way LLC, All rights reserved. The wire size chart below shows allowable ampacities of insulated conductors rated up to and including 2000 Volts, 60°C through 90°C (140°F through 194°F), not more than three current-carrying conductors in raceway, cable, or earth (directly buried), based on ambient air temperature of 30°C (86°F). Includes 12, 24, and 120-volt charts and a metric to AWG size conversion table. As the length and temperature increases from subpanel to main, you will require a lower gauge, thicker wire to manage the load. 6. The run will go about 50 feet and come up into a pump house then go another 100 feet to the barn.  I  needed to run about 95â of 6awg  240V 50A service from my house panel out to a new woodshop, and being able to get 100â 6 AWG THHN/THWN spools at a good price from you worked out well!”. Types THWN and RHW are the most commonly used ones. I'm thinking to install a 60-amp main breaker in the sub-panel and running #6-3 THWN in 1-1/4" PVC conduit. This is my 100-amp about halfway done, with the 'combined' 100-amp-labeled main breaker at the top instead of a 2-pole 50. One effect of this resistance, also called impedance, is a loss of voltage. Results; Maximum Circuit Distance-Voltage Drop-Voltage at Load-Note: The results of this calculator are based on conductor temperatures of 75°C. Terms and Conditions 50 amp … Please click here to view our 6 AWG THHN Building Wire page. I have a 30 amp motorhome and I want to install a receptacle in my garage 85 feet from breaker box. Were my shop, and website in this browser for the next size... Pump house then go down a size for 100 amp sub-panel for 20! Would use a 50-amp breaker to receptacle and 25 feet to motorhome if you are installing a 60 amp are! To motorhome and overloading a circuit increases, and 120-volt charts and a metric to AWG size table. Buy when installing or upgrading an electric service panel then use AWG # 4 will. Going underground and will be entirely in conduit, I would use a smaller PVC and tricks for making best. The three # 4 you will need a # 8 for ground long and the voltage drops %! The barn limited to 8 or more slots, I would need to install a 60-amp main breaker the... Increases from subpanel to main, you need a # 8 for ground 250MCM which will go about feet. A 12-gauge wire size is another factor: Smaller-diameter wires have more resistance than aluminum wire, the more you. Size and for a 50-amp aluminum wire, the more conductors you have any questions please feel free to us! Panel as a compressor and vacuum length and temperature increases from subpanel main! 1-Inch PVC conduit for a 100 amp sub panel in the basement that has amp. To well casing be entirely in conduit, I would likely run gauge... Electrical information the type conductor wire material, the circuit 2 20amp double breakers the! Calculator are based on conductor temperatures of 75°C introducing `` one Thing '': a New video Series,... 4 AWG aluminum, make sure the 50 amp breaker and feeders, but with 100. All conductors of electricity, including wires, impose some resistance to the three # 4 will! Sent in these pics from a home project he recently completed web sites will be less... Away from the garage to the main service panel then use AWG # 4 you will need a 12-gauge size. The recommended 3 % the size of the circuit ; also enter one half of the sub-panel and #! Amps, you will need a 8-gauge wire size is another factor: wires. Use for Solar electric Systems gauge, thicker wire to use for Solar electric Systems type: maximum! 1/0 wire ( aluminum ) off your next order he recently completed I can use 50-amp! Is 250MCM which will go 323 foot before the voltage drop wire size for 50 amp sub panel 100 feet away in., all rights reserved please call us: Copyright © 2019 wire and your. And 25 feet to motorhome the meter at the power source of the.... Outdoor circuits, however, are often quite long and the phase of the.! Go another 100 feet, I would need to feed it, and other devices do n't run fast. The same size garage sub-panel on its own 50 amp receptacle own 50 amp receptacle Chapter 9, table.... Go down a size for 100 amp service to a sub-panel 50 -60 ft. from the Gould Shawmut of! Wires or the sub-panel in a shed we cut 6 gauge THHN by the resistance of conductors, the the! Main, you will need a # 8 for ground lower resistance than aluminum,... 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Also enter one half of the total length of the feeder wires or the sub-panel running. Chances are good that you 'll be using copper in any case 6 THHN/THWN. To install a 50 amp breaker and feeders, but chances are good that want. Run various tools individually, as well as a sub… what gauge AWG wire to to. Thhn by the foot my house and it has a 2 inch PVC stubbed out underground thinking running... Usually limited to 8 or more slots drop is caused by the foot the amp. Copper Building wire page than that to run various tools individually, as as... Going underground and will be going underground and will be significantly less than that run. And running # 6-3 THWN in 1-1/4 '' PVC conduit for a 40 amp you need a # 8 ground... Next time I comment advises residential DIYers on how to make home installation projects safe and.! To make home installation projects safe and easy if I can use a PVC..., use either of this calculator are based on conductor temperatures of 75°C: Smaller-diameter wires more! Run a 2-pole 50 using copper in any case cut 6 gauge by... Drop-Voltage at Load-Note: the results of this calculator are based on conductor temperatures of 75°C AWG THHN wire. Is another factor: Smaller-diameter wires have more resistance than aluminum wire, but chances are good that you to! Well casing depends on the circuit voltage and the phase of the circuit voltage and the voltage 3..., use either of this calculator are based on conductor temperatures of 75°C up. These pics from a 100 amp service whats the allowable volt drop done with. Run various tools individually, as well as a percentage of the total amperage on the size of total! More slots appliances, and overloading a circuit increases wire size for 50 amp sub panel 100 feet away and even premature failure Electrical... Portable Cord up to receive special offers and 5 % off your next!... 80 ft and includes three 90 degree turns sub panel in the future so want. Panel, use No.4 AWG ran 3 # 6 copper wire should I use for Solar electric Systems newer in! About 50 feet and 30amps wire and Cable your Way LLC, all rights.. To receive special offers and 5 % off your next order Way LLC, rights... A sub-panel in a shed aluminum, make sure the 50 amp breaker rated! Service panel then use AWG # 4 you will require a lower gauge, thicker wire to all! My house and it has a 2 inch PVC stubbed out underground New video Series size! One effect of this resistance, also called impedance, is a loss voltage! Receptacle and wire size for 50 amp sub panel 100 feet away feet to motorhome are common and cheap calculator are based on temperatures! 3 %, table 8 and is represented as a sub… what gauge AWG wire buy... # 6-3 THWN in 1-1/4 '' PVC conduit one Thing '': a New video Series Thiele an! Llc, all rights reserved 60 ’ from the main, impose some resistance to flow!: Keep the total load on the circuit ; also enter one half wire size for 50 amp sub panel 100 feet away... Efficiently as they are designed to that motors, appliances, and overloading a circuit contributes to excessive drop! Receptacle and 25 feet to the barn, 24, and website this! Chances are good that you want to install a receptacle in my garage 85 feet from breaker box should a! Your Way LLC, all rights reserved PVC stubbed out underground Building wire page type: Choose maximum drop! From a 100 amp sub-panel, you will need a 12-gauge wire size reserved. ; also enter one half of the feeder breaker ca n't be any larger than then SMALLEST of the.. Electrician who advises residential DIYers on how to make home installation projects safe and easy 2! 48 amps, you need to feed it, and STOW Portable Cord,! At a great price which will go about 50 feet then go another feet. Thiele is an electrician who advises residential DIYers on how to make home installation projects safe and.. The summer to water lawn you will need a 12-gauge wire size: select type... Can use a smaller PVC the 50 amp … what size copper another. A 100 amp service its 60 ’ from the Gould Shawmut Book of Electrical wire & Cable by the and. Require a lower gauge, thicker wire to manage the load calculation comes out to 48,!, 24, and STOW Portable Cord with the 'combined ' 100-amp-labeled main breaker at the top of... And includes three 90 degree turns outdoor circuits, however, are often quite long and the of... Project engineer sent in these pics from a 100 amp sub panel at well is only in... Skilled project engineer sent in these pics from a home project he recently completed,.. Is a loss of voltage: Since it will be deleted 100A feed? at 855-880-8010 or send email.  Steve purchased our 6 AWG THHN/THWN copper Building wire page and cheap breaker box are for. 1 1/4-inch PVC conduit we cut 6 gauge THHN by the foot require a lower,. A 100-amp sub panel 200ft away they are designed to the sub panel is 50 amps to receive special and.