100 amp sub panel ground wire size

Runs don't look excessive, so 12Ga for 20A and 14 Ga for 15A should be fine for wire sizes. For a 70A breaker, #4 Cu. For 80A, #2 Al. For 100A, either #3 Cu or #1 Al. (It may be weird to get 30 extra amps for a 1-unit size bump, but remember - we can use the 75C column at 100A).

100 amp sub panel ground wire size. Seems the old forum said I could use 4/3 w/G NM conductor for 100 AMP sub panel (being fed from 100 AMP new service in this residential dwelling... Menu. Home. Forums. ... Conductor size for 100 amp sub panel? Thread starter vliposky; Start date Apr 4, 2007; Status Not open for further replies. ... Yes and also #2 NM 4 wire . Dennis Alwon ...

That would depend on a few things before I would automatically do that. First one is what panel/series, or other equipment is involved? Fused switches? You need a 200 amp switch to hold a 125 amp fuse instead of a 100 amp switch - more $$$ Miniature series breakers - I am mostly familiar with QO series - there is a price jump from QO2100 to QO125.

60 ampere double pole breaker in the main panel. 6 AWG copper wire (x4) for a run less than 75ft., 4 AWG copper wire (x4) for runs less than 150ft. 60 ampere panel with 60 ampere main breaker. Unless you're running a whole bunch of stuff at once, a 60 amp panel should serve you well.If you have electricity, you probably have an electrical panel for it, too. Also called a load center or breaker box, it takes your main source of electricity and divides it up bet...A 40 amp breaker needs a minimum of 8 gauge, larger gauge won't hurt. If using 39 amps (actual) at the same time, then you might need to use a 50 amp breaker with 6 gauge wire minimum. If sub panel is in the same building then I think you only need the ground wire back to main. - crip659. Jul 12, 2022 at 23:08.This Transfer Switch's output is then powering a 200Amp service panel. The Generator's max output is 100A (24kW @ 240V), and it also has a 100 Amp main line breaker on the Generator itself. When wiring (3-wire) to the generator, can I to wire for 100A (e.g. 00 aluminum wire)? Or do I have to wire for 200A (e.g. 0000 aluminum wire)?It is important to remember that the size of the ground wire should match the size of the other wires that come into the subpanel. ... Yes, you can use #4 wire for a 100 amp sub panel, as long as the distance between the main panel and the sub panel is less than 90 feet. The National Electrical Code (NEC) allows #4 AWG copper conductors for a ...The proper wire size must be determined for a 60-amp sub-panel to be installed safely and effectively. The requirements of the particular application, distance, and voltage drop all play a role in the wire size. Choosing the appropriate gauge reduces the possibility of electrical hazards and guarantees peak performance. Knowing the correct wire size is […]

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). Search Amazon for your Electrical ...Sep 17, 2023 · The size of the ground wire for a 100 amp service depends on the type of wiring used and the distance between the electrical service panel and the grounding electrode. It is best to consult a licensed electrician to determine the appropriate size. Ground Wire Size Calculator. The Ground Conductor Size Calculator will calculate the proper ground conductor size for grounding raceways and equipment based on ampere rating or setting of automatic overcurrent protection device in circuit ahead of equipment. This is based on NEC NFPA 70E Table 250.122. Search Amazon for your Electrical products ...My detached garage has 100-amp 3-wire service from the main panel in my house, with a 100-amp breaker at each end of the feed. The grounds and neutrals are bonded inside the sub panel due to the lack of grounding conductor (garage was built pre-2008 so I understand it is grandfathered into code). ... 70 amp sub panel wire size. 8.Standard wire sizes for a 200-amp residential service could be as follows: 1. Copper Wire. 2/0 AWG (American Wire Gauge) copper is a standard size for a service entrance conductor (from the utility to the main distribution panel). You may need 3/0 or 4/0 AWG copper for the leading feeder conductors, which run from the main distribution panel to ...

When choosing the wire for a 100 amp subpanel, you need to make sure that the wire gorge is sufficient for the amperage of the sub panel. Generally, a 100 amp sub panel requires #4 copper wires or #2 aluminum wires. 100 amp sub panel wire size: Generally, the wire that is suitable to run a 100amp subpanel is #4 copper wires or #2 aluminum …The 60A breaker feeding the 6/3 (I hope it's copper) will limit the current to the subpanel to 60A per 120v leg. The panel must be rated for a minimum of the size of the breaker feeding it. You can put as many breakers in the panel as the panel will hold, you just can't concurrently use loads that will exceed 60A per 120v leg.But if the sub-panel is located in a detached building, let us say the garage, then you also need to "ground the panel" by running a wire from its ground bar to planet Earth (e.g., to a ground rod or two). That wire would be the GEC that Bob mentioned, and it is sized per 250.66.Ground Wire Size Calculator. The Ground Conductor Size Calculator will calculate the proper ground conductor size for grounding raceways and equipment based on ampere rating or setting of automatic overcurrent protection device in circuit ahead of equipment. This is based on NEC NFPA 70E Table 250.122. Search Amazon for your Electrical …

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Wire size for 100 amp basement sub-panel. Have a 200 amp main in my attached garage. I am adding a 100 amp sub-panel in my basement to run all my basement circuits (2 bedrooms, office, living room, wet bar, bathroom). I have a panel with breaker set in the basement, and already have the 100 amp breaker to go in the main in the garage, but need ...For 150 amp, you will need a 1/0-size copper wir e size. For a 200 amp service, you will need a 250 kcmil-gauge copper wire size. For a 400 amp service, you will need a 600 kcmil-gauge copper wire size. For 600 amp, you will need a 1500 kcmil-gauge wir e size. We've got you covered if you want to buy a circuit breaker or a sub-panel.Generally, for a 100 amp sub panel, you'll need a grounding conductor that is at least #8 AWG copper or #6 AWG aluminum. First and foremost, you'll need to check the local electrical code requirements. When it comes to determining the ground size for a 100 amp sub panel, there are a few factors to consider. So, let's dive in!I was asked to give an estimate for wiring an apartment above an existing residential garage. Currently there is a 100 amp panel located in the garage that is fed with 4-3 romex from a 100 amp breaker located in a 200 amp panel located in the main house. I'm aware that according to article 334.80, romex is only rated for use in the 60 deg column.

I agree with Greg you can put in any size sub panel. Other than the panel size having to be the same or larger than the feeder breaker, the limiting factor is the wire size feeding the panel that is what sets the feeder breaker you can feed a 100 amp panel from a 10awg wire with a 30 amp breaker. I have done just this.Oct 2, 2023 · To run a 100 amp sub panel off a 200 amp main panel, feed the ground wire through the PVC conduit and secure it to the main panel’s ground bar. Secure the other end of the ground wire to the sub panel’s ground bar. Next, wiring a subpanel with 3 wires typically needs you to feed the feeder wire through the PVC conduit. Wire Size Calculator. Enter the information below to calculate the appropriate wire size. Voltage - Enter the voltage at the source of the circuit. Single-phase voltages are usually 115V or 120V, while three-phase voltages are typically 208V, 230V or 480V. Amperes - Enter the maximum current in amps that will flow through the circuit.The terminals in the sub panel where the conductors will connect. We'll then use the lowest value, or 60°C if any of the above are not labeled. Once we know the size of the overcurrent devices, and the lowest temperature rating, we can use Table 310.15(B)(16) to determine the conductor size and material we'll need.This video demonstrates How to wire and properly ground a 30 Amp sub-panel. Perform at your own risk. If not comfortable, do not perform.This is a sub panel. It is being fed and protected by a 100a breaker. 8-104 (1) says the rating of the feeder is the breaker or wire whichever is smaller, therefore it is 100a rated. No loads were given, even if they were, you still have a tub that is 100a rated, and a breaker that is 100a rated.Step 5. Run the wires into the service panel through the cable clamp attached to the knockout. Secure the wire by tightening the cable clamp to ensure that the wires will not move. Connect the black and red wires to the 50-amp breaker and tighten the screws. Connect the neutral wire to the neutral bar and the ground to the grounding bar.180. 180. From the above table, if we apply the 83% rule, then the minimum required conductor size must be calculated for 83% of 100 Amps i.e., 83 Amps. So, the 100 Amp Wire Size with an 83% rule is AWG 4 for Copper Conductors and AWG 2 for both Aluminum and Copper-Clad Aluminum Conductors.00:00 - What size wire do I need for 100 amp service?00:41 - Can I run a 100 amp sub panel off 200 amp main?01:10 - Can you use a 200 amp meter socket for 10...

The minimum width is 30 inches or the width of the panel, whichever is greater. The depth, i.e. the distance between the front of the panel and any obstructions, needs to be at least 36 inches. The minimum height is 6-1/2-feet. A good comparison for the clearance space, says Williamson, is the size of a standard refrigerator.

The Oriented Strand Board is a popular structural wood panel because of its versatility and durability. They are widely used for sub and single-layer Expert Advice On Improving You...The most wired countries in the world refers to the countries that have the best access to the Internet's resources. Learn about the most wired countries. Advertisement The Interne...I'm going to be running a circuit out to a detatched garage for a 100 amp sub-panel. I'm going to use 4 conductor USE aluminum for the feeder underground (2 hot legs, a neutral, and a seperate ground). Can I use #2 Al for my feeder per section 310.15(B)(6) or do I have to use #1 Al per 310.16?I am installing a 100 Amp sub panel in my detached garage for a 40 Amp car charger It is 70' away, 30' in the basement and then 40' outdoors. I am going to be running it using XHHW 1/0,1/0,1/0,2awg Aluminum wire in 1.5" PVC conduit.Aluminum is a lot cheaper, especially for long runs, but the size of wire needed for a typical 100 amp sub panel in garage or shed may exceed what the sub panel can handle. That is, as an example, the lug in sub panel can handle #1-4 wire, whereas you may need bring in a 1/0 wire due to the fact you have a long run.That cost can increase depending on how far the incoming wires are from the main panel and how close the water pipe is to the main panel. In most situations grounding a 200 amp service simply involves adding a second ground clamp where the ground wire attaches to the water pipe. A hydro inspection fee of $96.00 is required on any electrical work.When selecting a wire size for a 100 amp sub panel, it is crucial to choose a wire with an ampacity that exceeds the current rating of the panel. This ensures that the wire can safely handle the maximum load without overheating. In general, for a 100 amp sub panel, a wire size of at least 3/0 AWG copper or 4/0 AWG aluminum would be suitable.I have a 100 amp service run from my main 200 amp service at house run to pool building. I want to run electric from pool building underground to a detached garage. I'm wondering what size wire to run and what amp panel in garage. Garage would use some lights,door opener and run 120 v equipment such as air compressor,flux welder, small propane ...

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I am installing a 100 Amp sub panel in my detached garage for a 40 Amp car charger It is 70' away, 30' in the basement and then 40' outdoors. I am going to be running it using XHHW 1/0,1/0,1/0,2awg Aluminum wire in 1.5" PVC conduit.Electrical - AC & DC - Wire Size for 150 Amp Subpanel - We're wiring a new house - 200 amp main panel and 150 amp subpanel. All of our high-draw equipment is on the opposite side of the house from the main panel, so we'll be running very little directly from the main panel. Table 310.16 says 1 AWG THHN can handleStay with my existing 90 amp breaker. Use 1/0-1/0-1/0-2 Aluminum SER from the house panel to a junction box at the underground conduit point inside of the house. Use (3) 1/0 XHHW (two hots/one neutral) and (1) 2 awg XHHW (ground) out of the junction box, directly into the conduit, going into the garage.A 200-amp panel using three 2/0 AWG, it is recommended to use a 2- or 2.5-inch conduit for easier pulling. #2. Voltage Drop And Why Length Matters. Voltage drop can be easily explained as the voltage is less at the end of a run than it is at the start. As wires get longer, the resistance increases causing the voltage to drop.When it comes to the lines connecting master and secondary panels, where the line will carry as much as a full 100 amps, use a 2-gauge non-metallic sheathed electrical cable. The cable must contain one or two hot wires depending on your needs, one neutral wire, and one ground wire. Each wire should be 2-gauge in size.If a cold water pipe comes into the metal building it too would need a grounding electrode wire and clamp and bonding jumper over the PRV. Also from the disconnect you would run SER cable just like in step 1, to a main lug sub panel. 4/0 Al @ 75 deg is good up to 180 Amps [See NEC Table 310.15(B)(16)].Wire Size For 100 Amp Sub Panel 150 Feet Away. Alright, as we have calculated before, we need at least 125 ampacity wire to handle 100 amp current. Now we need to add the 30% amp boost (+20% per every 100 feet, hence +30% for 150 feet) to these 125 amps: Min. Wire Ampacity (150 ft away) = 125A × 1.3 = 162.5 Amps.I am running 100 amp line from my service panel to my subpanel through 100' of underground PVC. I have to use copper per local code. I am going to use #3 Cu for my two hot wires. 1) What AWG size does my neutral wire have to be? I found this: Per NEC Sec. 220-22. ….

I need to run power from my house out to my 35X70 workshop out back. What I have; a dedicated panel with 150 amp breaker on the side of my house that is currently only powering my well. My workshop is 275 ft. away. I intend on putting a 100 amp sub-panel in the shop. I have most of the 2" conduit ran in a trench from my house to the workshop.Wire size depends on breaker size (can be larger than the breaker but can't be smaller). ... GFCI in a 3-wire sub panel with bonded neutral and ground. 1. ... Un-conduit 3-3-3-5 CU SER feeder cable through studs for 100 amp sub panel 4 ft away. 2. Wire type from meter base to panel, conduit end to end, underground, and through a crawl space. 0.Service Panel Size : Copper Wire : Aluminum Wire: 50-amp service: An 8-gauge, 3 conductor wire: A 6-gauge 3 conductor wire: 60-amp service: A 6-gauge 3 conductor wire: A 4-gauge 3 conductor wire: 100-amp service: A 4-gauge 3 conductor wire: A 2-gauge 3 conductor wire: 150-amp service: A 2-gauge 3 conductor wire: A 1/0 gauge 3 conductor wire ...Install a 30 amp double pole breaker in the panel in your house, and run 10/3 w/ground out to the RV panel. The panel should come factory wired, so all you'll have to do is connect your feed wires. answered. 132k. I think that, as @brad says, this needs either separate neutrals (5 conductors) or an upstream double-pole breaker.Total run distance from main panel to sub-panel is 80 ft and includes three 90 degree turns. Burial distance will be 18". 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. I hesitate using direct buried cable as it seems a bit more vulnerable (but I'm no expert).What Is The Size Of A Solid Copper Wire For 40 Amp Breaker Quora. Setting Up My Geerage Page 5 Grumpys Performance Garage. What Wire Size For 100 Amp Sub Panel That S 200 Feet Away Upgraded Home. Wiring A Breaker Box Bo 101 Bob Vila. Sub Panel Installation With How To. Wire Size For 200 Amp Service What 100 150 Feet Away Nec. Ground Wire Size ChartThe Square D Homeline 100 Amp 12-Space 24-Circuit Outdoor Convertible Main Breaker Load Center for Plug-on Neutral breakers is UL listed for residential and ... Each pole space accepts full-size, tandem or quad breakers. Ground and neutral bars accept up to (3) #10-14 equipment grounds. ... Sub-panel Breaker Boxes. Outdoor Breaker Boxes. 100 ...Aug 20, 2023 · I am adding a 100 amp sub panel off the 100 amp main breaker. Don't understand the directions on what wire size to use. I bought the PowerMark Gold 100 Amp 32-Space 32-Circuit Indoor Main Breaker Circuit Breaker Panel. I was going to use a #6 stranded wire for for ground and 3 #3 stranded wire. Is this correct? 100 amp sub panel ground wire size, Seems the old forum said I could use 4/3 w/G NM conductor for 100 AMP sub panel (being fed from 100 AMP new service in this residential dwelling... Menu. Home. Forums. ... Conductor size for 100 amp sub panel? Thread starter vliposky; Start date Apr 4, 2007; Status Not open for further replies. ... Yes and also #2 NM 4 wire . Dennis …, That would depend on a few things before I would automatically do that. First one is what panel/series, or other equipment is involved? Fused switches? You need a 200 amp switch to hold a 125 amp fuse instead of a 100 amp switch - more $$$ Miniature series breakers - I am mostly familiar with QO series - there is a price jump from QO2100 to QO125., With the 80% NEC rule, the best wire size for 100 amp service is #1 AWG. Now, this is the correct wire size for a sub panel that is close to the electric device you want to run. What is the sub panel is 100 feet away? You will need a bigger wire, and here’s how you determine the 100 amp wire size for sub panel 100 feet away:, What 125 Amp Wire Size You Need. When determining the 125 amp sub-panel wire size, there are two types of 125 amp wire sizes: 1-gauge copper and 2/0 aluminum. Both have their own advantages, depending on your individual needs. 1-gauge copper is the most common type of wire used in residential and commercial circuits for …, Adding a 60amp sub panel (4breakers) on the 2nd floor for a dehumidification system and some misc. Running 100 feet of 6/3 wire. I am assuming that I can use the ground wire in the 6/3 from that sub panel ground bar to the main panel ground bar. This is not in a separate building so I don't think NEC requires grounding rods., The wire size needed for a 100 amp sub-panel depends on the distance between the main panel and the sub-panel, as well as the anticipated load that the sub-panel will be handling. Generally, for distances up to 100 feet, a #3 AWG copper wire or a #1/0 AWG aluminum wire is suitable for a 100 amp sub-panel., This is a sub panel. It is being fed and protected by a 100a breaker. 8-104 (1) says the rating of the feeder is the breaker or wire whichever is smaller, therefore it is 100a rated. No loads were given, even if they were, you still have a tub that is 100a rated, and a breaker that is 100a rated., The wire size needed for a 100 amp sub-panel depends on the distance between the main panel and the sub-panel, as well as the anticipated load that the sub-panel will be handling. Generally, for distances up to 100 feet, a #3 AWG copper wire or a #1/0 AWG aluminum wire is suitable for a 100 amp sub-panel., A: The size of wire for a 3-phase 100 amp service is determined by the distance between the main panel and the sub-panel, the type of insulation, and the conductor material. Copper wiring is recommended to be between 1/0 AWG to 3/0 AWG, while aluminum wiring is recommended to be between 2/0 AWG to 4/0 AWG. Q: Can I use #4 copper wire for 100 ..., About 200-Amp Service Wire Size. The National Electrical Code mandates a maximum #2/0 AWG or #4/0 AWG copper wire coiled within a standard 1.5-inch PVC 40 or 80 conduits for underground service. When installing three inputs in the same conduit, we suggest 2 or 2.5 inches. You should use copper or aluminum-coated wires that measure at least AWG ..., 3370 posts · Joined 2008. #3 · Jun 16, 2011. I doubt you will be able to find romex large enough to handle 100 amps. #2 is listed in Southwire's catalog, with a 95 Amp rating. I suppose you could special order a reel of the stuf, but it will probably be cost prohibitive. #3 THHN in conduit, with a #8 ground (if using PVC) is sufficient for ..., A 200-amp panel using three 2/0 AWG, it is recommended to use a 2- or 2.5-inch conduit for easier pulling. #2. Voltage Drop And Why Length Matters. Voltage drop can be easily explained as the voltage is less at the end of a run than it is at the start. As wires get longer, the resistance increases causing the voltage to drop., Our most popular. Click here for pricing on #3 gauge THHN wire. 2.) #2 THHN/THWN-2 Wire for 100 amp sub-panel. Single Conductor #2 gauge THHN Copper Wire. Needs to be buried in a conduit. Click here for pricing on #2 gauge THHN wire. 3.) #2/3C with ground Tray Cable (THHN-PVC) for 100 Amp Sub-Panel. Multi-Conductor #3 gauge THHN Copper Wire., But 75 would be enough so it’s best to jump up to 90 or 100. 75a = 2 awg wire with 2.56% voltage drop this would also handle 90 amps to go up to 100 amp 1 awg wire would be needed. With older panels finding anything larger than is doubtful. With max loads listed #2 and a 90 amp breaker would give additional room. – Ed Beal., Let's assume you're installing 100 amp sub panel that's a little more than 100 feet away from the main panel. It's best to use a 3 AWG copper or 1 AWG aluminum and a 1 ½ inch conduit for it (or even a bit larger to make wire pulling easy). With a single-phase, you'll need at least 3 wires., 1 Power Factor is assumed to be 0.90. 2 Temperature Rating assumed to be 75°C. 3 Weights are approximate and do not include insulation weights. 4 Values Per 1000 feet. 5 Maximum length is based on a load that is 80% of the fuse size. Prove Productivity Impacts with Real-Time Condition Tracking. Easily Calculate Lost Hours on Remaining Work., When selecting a wire size for a 100 amp sub panel, it is crucial to choose a wire with an ampacity that exceeds the current rating of the panel. This ensures that the wire can safely handle the maximum load without overheating. In general, for a 100 amp sub panel, a wire size of at least 3/0 AWG copper or 4/0 AWG aluminum would be suitable., I have an outbuilding will be 125 feet from panel to panel. Sub panel in put building will be 100 amp. Main panel at 200 amp. Want to have a direct burial line 24 inches deep. Wet ground. What size wire? Will need two hot, one neutral, one ground. Load will be lights, fan hot wTervheater on demand for one sink electric wall heater., Electrical - AC & DC - 100 amp sub panel pole barn - What size wire & type would i need to run 100 amp to pole barn approx. 150ft. from main?Would #6 copper do & what size aluminum would do?Plan to run through conduit 18 underground,also plan to put 100amp main in sub at pole barn.Am i ok by running #8 or #1, Im planning on doing a sub panel in a detached garage, from panel to panel is 210ft. My plan is to bury 2" PVC 18" deep (from top of PVC), run three 2/0 Alum xhhw-2 feeders for hot-hot-neutral, one 4AWG alum xhhw-2 ground, to the unbounded 30 space 200amp (rated) sub panel. Upstream breaker will be 125amp, down stream will leave the 200 (just a ..., I have a question regarding the size of ground wire to run from my main panel to the sub panel In my garage 60 feet from the house that has the following characteristics; - (3) 4 AWG wires for a 70 amp feed. - 70 amp breaker in main panel protecting wires. - 1" Sch 40 PVC conduit Buried., 100 Amp Sub-Panel. 25 feet away as the crow flies (45 ft. wire from panel to panel). US, CA ... and a bare or green ground wire. 1 1/4" pvc conduit is the correct size for this run if done in aluminum xhhw wire. Though I would personally use 1 1/2" pvc in case you want to add any switching from the house to the outbuilding in the future., The average wire size for a 60 amp sub panel is 6 gauge copper wire or 4 gauge aluminum wire for the hot and neutral connections. For distances of 100 feet or more, use a 3 gauge wire. There is a constant debate between a 3 gauge and 4 gauge wire., We would like to show you a description here but the site won't allow us., Even a 12-space panel will run out of spaces before it runs out of power. So I would advise something more like a 24-space, even a 30 would not be excessive. Breaker spaces are laughably cheap compared to the cost of having to change out a panel because the originally-chosen one was too small. There's no worry if the bus rating of the panel ..., I'm going to be running a circuit out to a detatched garage for a 100 amp sub-panel. I'm going to use 4 conductor USE aluminum for the feeder underground (2 hot legs, a neutral, and a seperate ground). Can I use #2 Al for my feeder per section 310.15(B)(6) or do I have to use #1 Al per 310.16?, So, a 250 kcmil wire is ideal for 200 amp. The size depends on how far you run the wires from the sub-panels to the main panels. The wire has to be at least 2 AWG thick. However, it also depends on the cable length. If you run a wire 200 feet away from the main electrical panel, use a minimum of 1-gauge copper wire., A subpanel requires two hot wires connected to a 240-volt double-pole breaker in the main panel. It also needs a neutral wire and a ground wire. The cable used for this run is known as a "three-wire cable with ground." The two hot wires, called feeder wires, will provide all of the power to the subpanel., For a 50-amp sub-panel, use #8 THHN wire; for a 100-amp sub-panel, use #2 THHN wire. Connect the main panel to the sub-panel box with the cable. Run black, red, white, and green wires from the sub-panel box to the main panel box. Keep the copper wire inside if the temperature is cold outdoors to keep it warm., Jun 28, 2017. #1. Can anyone enlighten me on which NEC version (year) it became a "shall" to bond a "sub-panel" enclosure separate from the Grounded conductor? I am sure it was prior to 1947. In other words 4 wires to a "sub-panel" I have looked and looked and cannot find a definitive answer. I instruct a large number of home inspectors and ..., The old wiring is 100% irrelevant to this, since you know it isn't large enough for anything more than 30A. So ignore all that and the plastic box, etc. Except that you should replace the existing 30A dryer 10-30 receptacle with a 14-30 receptacle, which will be easy since the new subpanel will have ground going back to the main panel. You will ..., How a Subpanel Is Connected. When an electrician installs a subpanel, the usual process is to first run a feeder cable from the main panel to the subpanel. This is typically a three-wire cable with three insulated conductors plus a bare copper ground wire. The cable must have a wire gauge sufficient to the amperage of the subpanel—a 100-amp ..., That would depend on a few things before I would automatically do that. First one is what panel/series, or other equipment is involved? Fused switches? You need a 200 amp switch to hold a 125 amp fuse instead of a 100 amp switch - more $$$ Miniature series breakers - I am mostly familiar with QO series - there is a price jump from QO2100 to QO125.