Understanding Wire Gauges | Ask This Old House

In this video, This Old House master electrician Heath Eastman teaches host Kevin O’Connor about wire gauges and the applications for different size wires.
SUBSCRIBE to This Old House: bit.ly/SubscribeThisOldHouse.
Master electrician Heath Eastman gives host Kevin O'Connor a lesson on wire sizes. Heath displays different wire sizes, ranging from thin to thick. He explains how each wire type gets its name and gives Kevin some examples of what each wire might be used for.
Wire sizing can be confusing. AWG? Aught? 14/2 vs 14/3? What does it all mean? Master electrician Heath Eastman teaches host Kevin O’Connor what these sizes mean and what wires of different sizes are used for.
Where to find it?
Heath explains the range in electrical wire gauges and how they vary depending on the load needed for a specific appliance. Electric current has a limited capacity dependent on the size of the wire. Circuits are available in different voltage loads to provide the exact amount of electricity required for a particular appliance. The larger the wire, the more current it can carry, meaning large wires support heavier electrical loads and smaller wires support lower loads.
Electrical wire can be found at your local home improvement store.
Looking for more step by step guidance on how to complete projects around the house? Join This Old House Insider to stream over 1,000 episodes commercial-free: bit.ly/2GPiYbH
Plus, download our FREE app for full-episode streaming to your connected TV, phone or tablet: www.thisoldhouse.com/pages/st...
About Ask This Old House TV:
From the makers of This Old House, America’s first and most trusted home improvement show, Ask This Old House answers the steady stream of home improvement questions asked by viewers across the United States. Covering topics from landscaping to electrical to HVAC and plumbing to painting and more. Ask This Old House features the experts from This Old House, including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor. ASK This Old House helps you protect and preserve your greatest investment-your home.
Follow This Old House:
Facebook: bit.ly/ThisOldHouseFB
Twitter: bit.ly/ThisOldHouseTwitter
Pinterest: bit.ly/ThisOldHousePinterest
Instagram: bit.ly/ThisOldHouseIG
Understanding Wire Gauges | Ask This Old House
/ thisoldhouse

[@Willp4139]

While the ‘k’ does stand for “kilo” and the ‘c’ stands for “circular”, “kcmil” is not a metric unit of measurement, and the “mil” is not short for millimeter. One mil is 1/1000th of an inch, and a circular mil is the area contained in a circle with a diameter of one mil. A 500 kcmil conductor, therefore, is a conductor whose cross-section has an area of 500,000 circular mils.

[@GeofDumas]

so theres a 1000x and /1000 in that unit?

[@literallycanadian]

@@GeofDumas Yeah, no one knows why it is the way it is, we just deal with it. It aint metric, thats for sure.

[@aaronclaar8748]

Great explanation - thank you!

[@jboy4real]

How many mm wire you can use for a single 10mm wire since the single 10mm wire is huge

[@kllgrogto5838]

You are wrong sir stop giving false info

[@ron.v]

Back in the late 1970s we ran 4/0 in our church, the job supervised by two master electricians. I recall the wire was so huge and stiff I thought we would never get it through the big conduit but we finally did. It was a service to a large air handling unit as well as duct heaters and other electrics for a portion of the building. I'm grateful for the explanation.

[@ganocd4]

4/0 aluminum is a standard wire size for most new 200 amp basic houses now. Ironically, aluminum is totally safe with a proper installation, torque, and anti-corrosion. Pulling the individual wires thru a conduit is an art if the conduit isn’t oversized.

[@ron.v]

@@ganocd4 I totally agree. I think our conduit was a little oversized but perhaps not. That was 50 years ago. We had no issues with large, professionally installed commercial wire back then. The issue we had was with copper-clad aluminum in residential installations. I'm no electrician but my brother was a licensed journeyman. We had to resort to copper-clad in my first home. Never had an issue because he taught me how to properly tighten all connections and double checked to make sure. A friend, on the other hand, almost had his house burn down. The problem was traced to a loose copper-clad aluminum connection in a plastic box. Yeah, I know, the plastic is supposed to be rated but it didn't do the job when the loose connection sparked and melted the wire. Fortunately the guy caught it and shut power before it got worse. It might not have ended well.

[@literallycanadian]

@@ganocd4 Ironicly? aluminum has been fine for awhile. Just need to have devices designed for it. All those big massive overhead powerlines? Aluminum.

[@dancooper6002]

@@ganocd4 A lot of fires have been started by Aluminum. It should be outlawed for residential wiring.

[@n9wox]

​@@dancooper6002I think your confusing aluminum with copper clad aluminum wire. Aluminum wire is still used in residential for running power to panels and cheaper than copper. Just apply antioxidant to the exposed aluminum wire.

[@cweeks19921]

Great video but I have a concern about the explanation for the "wrong wire for the job". If you use the wrong size wire, you're at risk for a fire (coming from inside the walls). It's not a matter of "the breaker is going to trip". Let's say the breaker was rated for 20A, but you put in wire that's only meant for 10A of current. In a scenario where 15A of current is being drawn, the breaker will think everything is perfectly fine yet the wire will be melting down and eventually light on fire. That's why it's important to put wire meant for 20A with a 20A breaker, etc etc

[@literallycanadian]

Yes, your breaker should always be sized to protect your wire. thats just common sense. What he was talking about was don't run a 14AWG on a 10A circuit to your oven. It aint going to get the job done.

[@cweeks19921]

​@@literallycanadian I'm not sure we should assume anything is common sense, especially when watching a video explaining beginner level concepts for electricity and wiring. But yes, I think you're right - that was his intent. But it was subtle, and could easily be misinterpreted as a safety point. Maybe it was just me. I wanted to help clarify and share knowledge, in case anyone else misinterpreted his point, as well.

[@beanapprentice1687]

This is correct. Choosing the wrong wire gauge has nothing to do with the breaker popping. That's a pretty big mistake for somebody (the guy in the video) who is supposedly a master electrician!

[@taqveem]

But what if I use a bigger wire than is required, is there any downside? E.g. using receptical wire for lighting?

[@riffnstrumguitarlessons9196]

So glad I read this.

[@iain3411]

25+ years as a UL508A industrial control panel builder. Mostly for the lumber industry boiler control, pump panels usually used the biggest wire. Great video on wire sizes.

[@SikoraStuff]

Appreciate videos like this. My high school students will be watching this in class next school year. I’d love to see more electrical videos! ⚡️

[@javiergalvan2604]

Great video as always! Learned something today 💥👌👍

[@danrich6448]

A good way to explain when to use 12ga (20 amp) to a home owner is on a circuit that will power an appliance that has a standard plug and cord, but produces heat. A toaster, coffee pot, hair dryer, space heaters, etc. It's more complicated, but this gets you most of the way there.

[@TheSipherArcher]

Love this! Thank you! More of this!

[@dddmmm21]

I would say more important than "right wire to the right appliance" is to say "right wire to the right breaker"... You get this combination wrong, that is when your house is at risk.

[@literallycanadian]

They are actually right, sequence of selecting devices is always appliance determines how much load you have, and thus determines required wire. Your breaker is now selected to protect the size of wire you have.

[@pauls.6360]

I'm still unclear about which two wires i should stick between my ears in order to receive the best This Old House reception. Oh wait, I now have the option to watch you on KZbin. Thanx guys.

[@Huntereconomic]

What an excellent video! THANK YOU!

[@ab-mn2yq]

Thanks for producing this video.

[@heidinewman9335]

This was so helpful. Thank you!

[@mmmodafoca]

excellent break down, i've learn something today.

[@leviathanfafner]

One thing you could have added was where "gauge" came from. it comes from the number of times the wire had to be drawn through a die or form to get it to the desired size. So, 14 gauge would would have been drawn through 14 sets of dies to get it to that size. Today it's a cross sectional area is more rigidly defined, but that's roughly equivalent to that. The X/0 sizes (pronounced "X ought") is just the number of 0s in that size, similar to "00 buckshot." Also should have mentioned that wire size is not only determined by the amount of current going through the wire, but also the length and duty cycle of the device you're powering. Consult you local electrical code or electrician for more information. And there was one mistake. MCM or kcmil is in imperial units. A mil in this context is 0.001 inches. en.wikipedia.org/wiki/Circular_mil

[@peterjanis2455]

ok bro maybe you should be in the video

[@johnlebzelter4208]

@@peterjanis2455 or maybe he shouldn’t. Probably isn’t even an electrician.

[@CoconutPalmPictures]

Thank you so much for that explanation! I've also heard it said that the gauge number is that fraction of an inch; for example, 16 gauge is 1 / 16 th of an inch. Is that true?

[@leviathanfafner]

@CoconutPalmPictures It might be a close appoximation in some of the smaller guages, but AWG scales differently. If you want the exact formula, it's on the wiki page for AWG: en.m.wikipedia.org/wiki/American_wire_gauge But to summarize, 36AWG is defined as 0.005 inches in diameter, and each size up is about 1.12293 times the previous size.

[@danrich6448]

The sizes range from 0000 (4/0) to 36. So 14ga is the 17th pass thru. 3/0 is the first pass. Length of wire (voltage drop) calculations can change wire size, but are for over 200 feet and rarely used in residential.

[@denelson83]

This stuff is good for us ham radio operators to know, because we want to know how much current our transceivers need, and then match the thickness of the connecting wires from our power supply for such amounts of current.

[@ryefry]

Love this show.

[@jeffclark2725]

Well said,I've enjoyed this show for so long,

[@MH-qq3kj]

Thanks Heath!

[@jake78787]

This was very helpful, thank you!

[@panama-sx2oh]

very good video im a electrician good explanation on the awg of wire n uses

[@johnhawkinson]

Heath got it wrong. kcmil is *not* "circular millimeters" and it's not metric. It is thousands (k for kilo) of circular "mils" where a mil is 1/1000th of an inch. (A 500 kcmil conductor is 253 square millimeters in cross-sectional area.)

[@eviltomthai]

What? Are you sure???

[@johnhawkinson]

@@eviltomthai Yes, I'm sure. Just google "circular mil" or "kcmil" and read a few of the top hits, or Wikipedia, or any other reference source. (I'd put a link here but then the comment goes into moderation and takes forever to show up.)

[@johnhawkinson]

@@eviltomthai Wikipedia: en.wikipedia.org/wiki/Circular_mil

[@C4PTAINinsano]

Need one for plumbing pipes snd connectors next. Abs, pvc, cpvc, Schd 40, schd 80. Etc

[@Sylvan_dB]

Include which are sized in Iron Pipe Size (IPS - abs, pvc, ...) vs Copper Tube Size (CTS - cpvc, pex, ...).

[@Hezkezl]

Kinda wish there'd been a closeup on that paper on the side near Kevin

[@zacburgess5318]

Pretty informative and a great video as always. Curious though, what would be recommended for a small workshop in a garage or barn? Mostly just a refrigerator or two and the occasional power tool or air compressor?

[@nachoisme]

Almost certainly you would be fine with 12AWG. Depends on the power tools and how much or many you would use at one given time. Getting power to the garage if it is detached would likely be the biggest issue

[@djscrizzle]

A 50 amp service to a main breaker type sub panel would be what I'd consider minimum. 100 amps would give some major flexibility for the future.

[@gtoalifachannel4229]

Ukuran kabel yang sangat pas buat peralatan industri dan mesin lainnya ❤

[@juliavanhoose]

I’m a substation engineer and we use some wires that are so big they have a 4ft plus bend radius. Interesting stuff!

[@ntw3394]

Danny Cho needed to watch this video.

[@vaelectrical]

Thank you for this great video sir. Just followed channel

[@ganocd4]

I’d love to see a n accompanying video on all the CAFCI and GFCI circuit breakers these branch wiring circuits connect to with a modern standard. The breakers are around 100 a pop and many houses need 30 of them to meet code these days. It’s too bad the BOM cost for these is so cheap and they are so overpriced relative to the chip and material cost in said breakers. They won’t protect against undersized wires, but they do catch a lot of faults you won’t typically find.

[@rafealborbon8482]

Congratulations you have passed the test you got it right

[@pong86r]

That explains a lot why we'd always trip the breaker whenever someone would use the hair dryer in one of the smaller bedrooms!

[@cyborg1117]

hi great video, i want to put level 2 charger in my garage its over 75 ft run which gauge wire should i use 4awg? And has to be in conduit, which conduit should i use? size ? material? code here has to be in conduit...thanks

[@jamesfazekas1432]

0:11 yeah what size wire should I use for an entrance 1 120 to 220 on a meter socket what size wire should I use

[@loganwalsh]

Wow those sizes are shocking 😮

[@forblocking9484]

hi! so what should i use if i have a generator that outputs 220 volts and has a 3,600 running wattage (4,000 watts maximum) and i want to connect a 1HP air conditioner directly to the generator outlet that outputs 220v? btw, i know that i should use the correct connectors. I am just unsure about the gauge of the wire itself. Do I need an 8-gauge or would a 10-suffice? distance or cord length would be either 50 feet or 100 feet. TIA

[@Sylvan_dB]

The only reason to use 14ga is to save money. All the normal general purpose outlets should be wired with 12ga on 20amp breakers IMO. If you separate lighting from outlets (a good idea, IMO) then maybe you want to use 14ga for your lighting circuits. But then if anyone decides to add an outlet and feeds it from a nearby switch, that outlet will be on a 15amp breaker. Wire is cheap compared to an electrician's time to come out and add circuits. Just use 12ga for your outlets in the first place. Or 10ga. That would be even better, but man I hate working with that stuff and multiple cables in a box.

[@alexknight7191]

Agree with everything you said! In a few places with especially strict code (including where I live), 12ga is required. Your note about future changes sticking on 12ga wire/20am circuits is spot on.

[@virgil3241]

Yep, if a homebuilder can cut cost they will, and to hell with everyone down the line for decades that own that house.

[@n9wox]

With LED lighting, 14 gauge is almost overkill for lighting circuits, but it's still the standard for residential lighting.

[@Sylvan_dB]

@@n9wox Problem is we don't have really any standard for premise wiring less than 14ga/15a.

[@aidanray4846]

Completely not true

[@martinneosel3403]

I'm changing a length of 14/2 Romex on a 30 amp breaker but the length I have is a little short of the length I need. I've been told that since 12/2 Romex is thicker gauge than 14/2, it is not a problem to splice with 12/2 Romex with 14/2 Romex. Is that accurate?

[@wysiwig3]

Neither 14 or 12 AWG are rated for 30A. That breaker will trip when the draw exceeds 30, but the wires are likely to melt or catch fire first! Use proper cabling. You could run overrated wires, but not underrated. For example, if you have a 15A breaker you could technically run 12GA (rated 20A) from it to a junction point, and 14GA (rated 15A) to your standard 15A receptacle. I can't tell you if that would pass code inspection though.

[@lunam7249]

30 amp is really high and wierd ampere!...figure out what requires that

[@user-iu4eg9vq6r]

Will a 14 gauge wire carry less voltage and produce fewer watts than a 10 gauge? Thanks!

[@jmollo55]

My house is wired with the yellow but only two wire ...only ground is from box to water pipe and glass fuses and paper wound mains ... id dare say my box is only 75amp .. even the drop from street is half the size of rest of neighborhood ,,, house was partially rewired in the 70s ... all they did was run new wires to outlets

[@lunam7249]

dont tell anyone, thats not code..fix it yourself with 3 conductor 2 live + 1 ground....its needed for lighting strike and problems...lowers fire risk...fix that yourself soon..if an electric company comes in, by law they have to report it to the city you live in, fines, rewire, bs, time, $$$ , you fix it soon

[@Aranak777]

i have a 2 feet extension running hot doing 15 amp and the air fryer i use is normally running max 10 amp what would explain that

[@Sylvan_dB]

Too small of wire. Your "2 feet extension" is probably not even 14ga. Some devices with smart power supplies are designed to draw constant power. Power is volts multiplied by amps. If the volts drop it requires more amps to get the same power. I wouldn't expect an air fryer to be constant power though.

[@trustbuster23]

Get a better extension cord. They sell extension cords that can handle a light or two, but you need an appliance level cord for those amps.

[@Aranak777]

@@trustbuster23 should i got another one of better quality who do 15 amp or higher? i dont need more then 1 item plug on the extension the cable who came with the air frying is 1 feet long so to get to the wall i need another 2 feet

[@trustbuster23]

@@Aranak777 get an appliance extension cord, they sell them most places. Those thin brown or white cords can't handle the amps.

[@davidramey7186]

The color coding thing isn’t always accurate In the past I’ve personally seen orange that was not 10 AWG I believe it was 12 if I recall correctly

[@geekgirl913]

Yes, they should have noted color coding didn't start until the early 2000s. I have 12/2 in my house with a white sheath and the date on it is 1999.

[@VisionsTruth]

Any downside for using 10 AWG or 12 AWG when only 14 AWG is needed - other than maybe the cost?

[@c31979839]

Harder to bend

[@BradThePitts]

10 or 12 gauge also sometimes won't insert directly into the rear holes in electrical outlets.

[@leviathanfafner]

Wire may be too big from some of the terminal you plan to land into, like stab in receptacles or switches. But other than that it's fine to use oversized wire so long as the breaker/fuse/OCPD is sized correctly. Up-sizing wire is done sometimes on long wire runs (300+feet) to mitigate power loss from the wire resistance.

[@jasony9950]

@@BradThePitts don’t back stab (put it in the holes) of the outlets. ALWAYS use the terminal screw or a WAGO connector. Backstabbing wires causes wires to come loose.

[@scotttovey]

@@jasony9950 "Backstabbing wires causes wires to come loose." Well, there's something that wires and I have in common. Neither one of us like being back stabbed.

[@inspectorsteve2287]

If you aren't sure if you should use 12 or 14 can you just always use the thicker 12 for almost everything in your home?

[@leviathanfafner]

If you’re unsure, call an electrician.

[@dirtbike662]

I framed a storage unit complex. The electrician used 12 gauge for all outlets, lights, ceiling fans, water heater,garage door and gas heater. I'm sure he could have used 14 for most of it. If I build my own, I'm going as thick as I can.

[@inspectorsteve2287]

@@leviathanfafner hell no. This show is for DIYers. Trial and error is how it goes. Lol.

[@inspectorsteve2287]

@@dirtbike662 it's probably better to go too thick than too thin. (That's what she said)

[@leviathanfafner]

@Inspector Steve Well, trial and error with electricity tends to end with fire, shock, and "its going to hurt the whole time you're dying" death.

[@purplefurture6960]

Which iec c13 uk plug i should buy? I found ones has 10amp fuse and other 13amp fuse AC INPUT ：100-240V-3.5A 50-60 Hz DC OUTPUT：19.5V-11.8A 230W

[@roomadmin8035]

what's the glaring disadvantage of wiring the whole house with one or two kinds of lower AWG wire (to make it more powerful for multi-use need) besides cost$$$...so you can bring the blender into the bedroom per se (:P)???...and can a house be equipped with its own dedicated transformer to lessen if not eliminate / prevent surges and trips?

[@engrpiman]

I work with lineman. While most think 4/0 wire is huge they think it's "small"

[@literallycanadian]

I feel you. My site we are pulling in a total of 18 parallel runs of 3c 750 kcmil TECK to refeed a university campus. that 4/0 is the ground for the hangars and there is an extra 1/0 on top of the copper sheath and armour XD.

[@djscrizzle]

Just wait till ya see a transmission construction crew pulling 3x 892 Kcmil conductor between towers. A true artform in itself, especially with a technician installing spacers off a helicopter.

[@jneuman211]

Could you wire your whole house with 12 guage wire? Minus the bigger stuff. I.e. dryers.

[@KG12KG]

Yes, 12/2 could be all 15A or 20A circuits. Besides cost savings, the main advantage of 14/2 is the ease of wiring it. Lighter, more flexible, etc. I generally use 12/2 for nearly all my new circuits, mainly for future growth, but if the circuit is lighting only and LEDs, it is tough to justify 12/2.

[@jneuman211]

@@KG12KG Thank you. I am trying to gather as much info and knowledge as I can. My 1968 home needs rewired. The previous owner/s have feeds coming and going from multiple boxes. Example: the dryer and dinning room are connected somehow, because the breaker will trip foe the dinning room and the dryer stops working.

[@CPPRODUCTIONS1001]

I thought that was brendan Fraser in the thumbnail

[@Pallidus_Rider]

Actually, that is Brendan's electrican 😮😂😊

[@2loco]

😅

[@terencemerritt]

Same

[@lilal8848]

Lmao

[@DTHRocket]

I have 10/3 wire for connecting a 9000 W generator. Is that too small?

[@seaandearth]

what about the BX cable?

[@jptrainor]

So we should stop making margaritas in the bedroom? My wife isnt going to be happy.

[@Sylvan_dB]

No, it's fine. Maybe even recommended. Happy wife, happy life! (Seriously, if your blender has the normal 15amp plug, it fits correctly into a normal 15amp or even a 20amp receptacle and it is intended to work fine that way.)

[@GXTOLX]

Ac units usually require 6 2 wire with 40 amps. 6/2 can handle 55 amps. 8/2 is 40 amps for range.

[@JK-qe6qq]

Range needs 3-wire conductor not 2 !!

[@GXTOLX]

@JK-qe6qq can use 8/2 or 8/3 but latter is preferred

[@ThisNamesNowTaken]

Did i miss it or did they not explain what would happen if you use, for example, a 10AWG where a 14 AWG is needed? Using more where less is needed. I know they reversed that question and they said it heats up and trips switches.

[@mamaswamma1234]

Larger wire is fine, as long as breaker is sized appropriately. Just a waste of $$$

[@TybaltKaine]

Curious as to how long this standard has been in place. I'm currently living in a 1955 cookie cutter suburb house, and wondering if I need to see about updating my wiring to handle modern appliances that are in non traditional places. Things like heavy use, high end computing rigs in bedrooms, blenders and small appliances in an add-on that got turned into a guest house/in law suite. Really hoping I don't have to end up gutting my walls 7 years in.

[@alexknight7191]

Typically the main issue with older homes' electrical wiring is the lack of a proper ground wire. If your wiring lacks that, you really should have it fully redone at some point. The other issue with older homes is they aren't set up to carry the cumulative higher amperage draw of all those newer appliances. Your panel should have a main breaker on it or near it with the amp rating on it. If it's under 100 (50 or 75), you'll definitely want to consider upgrading the panel (which may also require upgrading your service, though it depends). If it's 100, that might be OK but it's tight, especially if you have an accessory dwelling. Most newer homes are built with 150 or 200 amp panels. My house is even older than yours, so I do plan to upgrade both the panel and the wiring at some point. If it's never been done, it really is something that needs to be addressed at some point. Now, very broadly speaking, if you've been there 7 years and you're not regularly tripping breakers (or fuses for some old houses) and seeing lots of flickering, you're probably not in danger of the house burning down. But the key word there is "probably". Having a licensed electrician inspect your home is always the best way to have peace of mind on those things. I will say you can look into having AFCI breakers installed (if your panel is new enough) by the electrician as a stopgap safety measure to prevent faulty wiring from causing a fire as it deteriorates. Good luck!

[@CarlosGarcia-ls4hn]

I have two Romex cables with a white exterior going to the first of three ceiling lights in my kitchen that are wired in series. Each Romex has two black wires, a white wire and a ground. Why two black wires?

[@cornellwilliams1248]

My name is Cornell I going to to Apex trainer school for electricity. I’m having a hard time reading the multitest readers. Can you please explain it or tell me in simple terms how to read one

[@rperez0406]

Can I run 14g wire on a 6-20r?

[@alexmaclean1]

When I wired my house I ran 12 for all circuits, mostly because I already had several rolls of 12 and I'd have had to buy more 14 lol. Otherwise it would have been perhaps a waste but now I don't worry about any voltage drop for running a big vacuum outside on the other side of the house lol

[@savageredbeard]

18 or 20 gauge for doorbells or garage doors (button or sensors)

[@bjornjoseph]

This is why my peninsula out let pops when i use the blender and mixer. But the out let by my stove handles it well. This think all kitchen outlets would be 20

[@justayoutuber1906]

I though it was, by code

[@gregscott989]

OK...let's not confuse power with current. Remember, Power = Voltage x Amperage...W = V x A. It's the current...A(mps)...that heats up the wire, not the Power per se. For example, a 100W load at 120V requires a little less than 1 Amp. At 240V, it needs half that, a little more than 1/2 an Amp. In an automotive system at 12V, a 100W bulb...say a headlight...requires a little over 8 Amps. AC or DC, it is the amount of current that needs a particular wire gauge, not just the amount of Power.

[@alexb2082]

But how do i know what power each one can handle?

[@dandonna852]

AWG vs other countries?

[@MrZYouTube]

I use 0 guage wires for my positive terminal car battery. Matched with 0 gauge wire star pattern :)

[@Farm_fab]

Trains are single conductor.😂

[@2loco]

Thank goodness for the simplicity of the metric system. Cable size is the cross sectional area in mm2. Generally in a domestic situation we use 1mm2, 1.5mm2, 2.5mm2, 4mm2, 6mm2, 10mm2, 16mm2. We use 2 core and earth (for single phase loads), and 4 core and earth (for three phase loads).

[@DnvGoodwin555]

Yes! Normally 1.5 for light. 2.5 for sockets. 4 or 6 for kitchen.

[@user-rv8kt9dp7p]

Electric wire can used 12v wire car?

[@bmay8818]

Oh come on, nowhere does anything suggest that a blender can't be plugged into a bedroom. I don't know where this guy got that from, that's ridiculous. If the plug goes in the receptacle, it will work. Sheesh.

[@arickbakken]

No 16 awg. I thought I heard that it will start to be allowed for lighting only since LEDs draw almost 1/10th of the power of incandescents. The code is currently assuming incandescents.

[@Sparky-ww5re]

Yes there is discussion on 10 amp circuits in the 2023 NEC, however 16 awg copper or 14 awg copper clad aluminum NM and 10 amp AFCI breakers are not yet manufactured. It's probably past time the code finally woke up to the assumption the days of 60 or higher watt incandescents except for special uses such as the heat lamp you might have in the bathroom, have been in the rearview mirror for a decade now.

[@sakenaphillips6347]

Bravo this helps me to buy my dryer wire so I dont get rob out their😅😅

[@bugtusslealien3931]

TOH, please, you should review the explanation this electrician provides.😂😂😂

[@vlaardingerrr]

Metric is way easier🤯 Here in the Netherlands and some other European countries in a new house: Mains connection is 3 fase, 230V, 25A with a separate neutral and ground. The wires inside the breakerbox are 6 mm2 thick. The circuit breaker are 16A with 2,5mm2 wires running to your outlets/lights (except the switch wire for the lights, this one is 1,5mm2). All the switches/outlets are designed for 16A 230V. Do you need more power, use 2 fase, and the neutral. Stil not enough, 3 fase and neutral. Still not enough, what are you doing with around 11000 watts on a single breaker? Yes you can get a 35A 230V mains connection and with that your allowed to install 20A 230V breakers, but this is expensive! The fee for only your connection with the grid is 3 times as high. The only time you maybe can see a 4mm2 wire in your house is when you have solar or a car charger more then 10 meters (33ft) away from your breakerbox. And yes there are 10 or 12 mm2 and thicker cables but not used for 99,99% of the houses.

[@JohnAranita]

Will using a wire too thin cause a fire hazard?

[@dionokeke2148]

I'm not an electrician but I believe so. Using a thin wire where a thicker wire should be used may overheat and cause a fire.

[@terrybest5611]

Would this feeder wire work coming from the main box at the house for a 50 amp RV service…175 ft ? bring the power from the residential, commercial, and industrial buildings to outdoor constructions, which include pumps and lighting constructions. The electrical cable is suitable for direct burial, as well as direct exposure to the sunlight. It is permitted for use as feeder or branch circuit cable if provided with overcurrent protection. Copper Underground Feeder Cable UF-B has a rating of 600 volts. • Size AWG: 6 • Weight per 1,000 ft: 303 lbs • Outside Diameter: 770X338 • Conductors: 2 • Number of Strands: 7 • Jacket: PVC • Insulation and Jacket Thickness: 35 mils • Jacket Thickness: 45 mils • Ground Size: 10

[@metzidis]

They should address the threats and protections. Breakers protect against fire in the conductor inside your walls but not outside . If you use the wrong gauge extension cable you risk a fire . Eg cheap extension cable with a space heater you will have a fire - your breaker can’t protect you. Always be mindful of the load . A lightbulb is only 100ma . A hair dryer is 10 amp. A space heater 15 amp and so on . More amps = fatter cable (lower awg number ) = more cost

[@jasony9950]

That’s a lot of money on that board ha

[@kalebmartinson]

stuff i should have learned in school

[@MaxC925]

kcmils is imperial, not metric.

[@sergeantsapient]

I've always assumed there should be no issue plugging in something to a lower gauge wire than what it needs other than perhaps being wasteful.

[@wucherer]

Aluminum verses Copper, why is aluminum used feeding power into a house than copper? Cost, since copper is more expensive than aluminum??

[@Tritium21]

Its not metric! Its K (thousand) C (circular) Mills (Thousandths of an inch) - its in the name! 250 kcmill wire has 126.7 mm(square) cross section - its not metric

[@backhand_snipe9943]

Can you go in reverse a bit? For example, add a 12g wire to a 10g outlet etc?

[@surferdude642]

There's no such thing as a 10 gauge outlet. 10 gauge wire is normally used for a 240v 30 amp circuit. You could use 10 gauge wire on a 20 amp 120v circuit and receptacle where 12 gauge is appropriate, but it would still be a 20 amp circuit. The only arguable cases for that would be for very long runs to mitigate voltage drop and in when an actual 20 amp cord and receptacle are required.

[@daveyt4802]

How about Aluminum wires? Different rules?

[@BetoFromLA]

Can u use 10 awg all around home? For outlets as well as ceiling fans ?

[@bb55555555]

This is a little misleading. Yes the colors are standard now but back in the day they were not. My house was built in the 70s and both the 12 and 14 AWG wire have a white jacket.

[@djamelhamdia134]

He specifically said "newer house".

[@bb55555555]

@@djamelhamdia134 ok fair enough. I guess I missed that part.

[@Victor-rs2ws]

why? its really disapointing how many questions are still left from electrician videos. why can't i run 8 AWG through the whole house?

[@GoatZilla]

Hey guy, leave the comedy routine for the comedy club.

[@SteelBlueVision]

It's all fun and games when you don't know what AWG stands for but are throwing GFCI around like everybody knows what those four letters stand for.

[@DnvGoodwin555]

God bless. We use simple square millimetres.

[@TheJeof1000]

i will use 12 awg on all my outlet.. just cost a bit more.

[@God7ODTaxationIsTheft]

Drat i was gonna bring the toaster in my bedroom and make toaster strudel

[@silentwolf9923]

What if I used 10/2 for outlets 😂😂😂😂

[@JakePlisskin12]

What about a fridge in the bedroom. A half sized fridge. Asking for a friend. 🤥

[@Sparky-ww5re]

2 wire cable is used for 120 volt circuits, and 240 volt circuits with no 120 volt loads, for example an electric water heater or central air conditioner; the white wire needs to be marked as a hot, black or red tape near the end of the wire at the receptacle or appliance, and at the breaker box is typically used. 3 wire cable is typically used as travellers between 3 and 4 way switches, for interconnected smoke/CO alarms, and for 240 volt circuits with 120 volt loads, electric ranges and clothes dryers are typically the only such loads in a house or apartment.

[@counterfit5]

Who is still using 14/2 for 120v circuits?

[@buh5995]

thanks god that they use names like amps, watts, wire, copper.. imagine what if american call watts as qooqi

[@jdmrc93]

Note, you could just run 20 amp 12/2 to all your outlets. Not much more expensive. If you have, say, a portable AC running (drawing more than 1000w), and god forbid you plug in a clothes steamer or something along those lines, it will trip the bedroom circuit. Speaking from experience.

[@roberthaselwood8737]

Our wire sizing needs to be updated and simplified. It seems antiquated by going high awg for lower amps then lower awg for higher amperage and then higher awg single conductor before switching to a metric system… I wish is just had the amperage rating instead.

[@literallycanadian]

No sense in changing now, just going to cause more problems that it would save. The only alternative is to go to metric in which case all the manufacturers have to re-tool because metric aint going to match up with AWG without being really akward decimals.

[@joeselzer850]

your missing 15 Gage and 16 Gage y3, and others ou skip some

[@Farm_fab]

18 awg is also used for cat 5 and phone wire indoors.

[@leviathanfafner]

Cat 5 is usually between 22 and 26 AWG, depending on application.

[@rcguymike]

No mention of length either...if you have a 2nd or 3rd story, runs out to a detached garage/shed you need to upsize in a lot of cases.