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It is easy and inexpensive to make home wiring into extension cords! Is this code compliant?

Romex is solid core wire. Flex that wire too many times (and too many is not very many) and the conductor will break. A loose connection (two wire ends touching) is going to get hot and start a fire.

The jacket on Romex is thin and weak. I hope I don't have to explain why that might be a problem.
 
I was reading this and thinking about my old extension cord with a timer going through a wall and to a 1000 watt electric heater I have in my van to keep windows snow and ice-free during the winter. I noticed the cord is finally falling apart after so many years.
There are specific codes that specifically point out, extension cords shall not pass through walls, and should only be used in temporary conditions, less than 90 minutes... the timer, May skirt that rule... but not the through walls part.
 
I have been using what is shown in the pictures for 10 years. After spending time online watching people install expensive critical load panels and dangerous back-feed systems I wonder why more people don't take this approach?
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View attachment 1121
For those interested in more details, read on. For others, I am basically just asking if it is code compliant to install a female plug and male plug in home wiring between the panel and the loads served by the wire (female plug goes to panel) as shown in the first picture. The reason to do this would be to allow the circuit (male plug) to plug directly into a generator or all-in-one solar system, bypassing the panel. The panel picture is just so you know what my US 200A 120V split phase panel looks like in case that helps.

More details...

If a generator (whether it be a gas powered generator or all-in-one solar/battery system) has a 15A or 20A circuit breaker built-in it seems to me this would be safe, but I am not a trained electrician. Installing plugs would not be as easy for panels in finished areas where wires are behind a wall, or for conduit protected wires, but for panels in unfinished areas like the one pictured (in an unfinished basement) this is a really inexpensive and easy way to get backup or alternative power to appliance circuits.

Pros
Easy to install the plugs in wires if they are not in walls or conduit.
I think it should be fire safe if the off grid supply (generator or solar system) has a breaker the same size or smaller than panel breaker serving that wire.
I think it should be electrician safe if the wires are labeled (on panel side and appliance side of wire).
I think it should be lineman safe because power from the generator completely bypasses the panel so it can not back-feed the grid(mains).
My favorite pro is that this allows other devices to be installed in the utility area where the panel is located instead of taking up space on outlets (things like Killawatt meter, iot smart switches, and RFprotect devices to protect refrigerator from brown outs).
Makes it easier to use all-in-one systems like the Yeti, Bluetti, and others in homes, especially if solar panels are used and the solar wires enter the home in the same area as the electric panel.
Makes it easier and cheaper to connect critical loads to a generator with breaker protected outlets during a power outage.
The male and female plugs are easy to find at most hardware stores, inexpensive, and there are several instruction videos online to show beginners how to safely select and install them.

Cons
May not be easy if wires are behind a finished wall or in solid conduit. If conduit is required, flex might be an option but would make install more difficult for beginners.
The installer must make sure the off grid energy source has a breaker appropriate for the wire.
Others? Is this not code compliant in most or all situations? Could it cause a failed home inspection?

The National Fire Protection Association (NFPA) has a web page that allows submitting questions about US national electric code compliance. This would probably be the most definitive way of answering this question, but only NFPA members or public officials can ask questions.


I may eventually look into joining the NFPA just to ask about this, but for now thought I would run it past the DIY Solar Forum to see what people think. Maybe someone on the forum is an NFPA member?

In the US there is a youth education program called 4-H that is associated with University Extension. 4-H offers youth electrical safety classes where electricians teach kids electrical safety with hands-on activities. One of the hands-on activities is to help the kids make extension cords using a wire, male and female plug ends, wire strippers, and a Phillips screwdriver. They teach the kids that small lamp cords should not be used for space heaters. They also teach them how to pay attention to cord size and device power use labels so they don't plug too many high draw appliances into one power strip. These classes are not available to all kids, and some kids forget what they learn (according to follow up surveys). I mention this to make the point that safely plugging in cords and understanding how to determine appliance usage is really the entry point of safely using electricity. If batteries continue to fall in price and all-in-one systems with breakers that match up with common home circuit sizes become more common this approach of using home wires as extension cords might help a lot of people safely and cheaply install solar even if they know only the basics of electrical safety and have a limited budget. I think it could possibly lead to quicker adoption of solar by making it more “plug and play”, but if it is not code compliant that will hold it back even if it can be done safely.
Hi Max:

By no means am I an electrical expert; less so a solar one--although I can drudge my way through the latter (solar), and converse in the former (home electric.)

Many posters above have talked about the fact that your use of male and female appliance plugs is not compliant and why (risk of fire, short, etc.). Breaks in such cables should only happen when necessary, and in a properly installed a junction box.

Where I though I might be able to add some useful commentary is in a subject area that you brought up that's been less addressed above, and one in which I have experience: the use of generators to power things in your home.

Many things in the home must be direct wired to the circuit breaker: for example, an electrical sparker that ignites (by design) the fuel in many home heating devices. The only code complaint way to get a generator to energize such a circuit is through a professionally installed UL 1008 complaint transfer switch.

That switch can be as simple as this manual, one circuit one, http://www.reliancecontrols.com/ProductDetail.aspx?TF151W expressly designed for what I describe above, or something automatic with numerous circuits to run an entire house's essential lines during a blackout, perhaps connected to an equally automatic generator that starts up when utility power is interrupted.

Either will have circuit breakers of their own.

Think about this...were you to unplug one of your circuits as shown in your initial picture, and plug it directly into one of the outlets in your generator (perhaps with use of an extension cord, but somewhat besides the point) you will have bypassed the circuit breaker that protects that circuit from fire. Notice how even the simplest of transfer switches, like the one I link above comes equipped with its own circuit breaker(s) so the line is still protected when run off the generator.

I suppose I could go into speeches about protecting the line workers from the backfeed of a cable that's energized by some homeowner not practicing UL 8001, but your setup would make it impossible for a generator to unintentionally energize any wires leading to the utility pole (I'll give you that.) Still more, line workers are trained to detect this.

Those 15 and 20 amp outlets you see on off the shelf big box store generators, they're suppose to be solely to connect appliances that don't necessitate being hard wired into your home's electrical system, complete with a male plug at the end, like toaster ovens. And of course the prior sentence should not be construed as implying such appliances be situated outdoors in potential moisture, as sure as any ICE (internal combustion engine) generator MUST be (situated outdoores) given the noxious emissions it gives off, not the least of which being carbon monoxide.
 
I have been using what is shown in the pictures for 10 years. After spending time online watching people install expensive critical load panels and dangerous back-feed systems I wonder why more people don't take this approach?
View attachment 1120

View attachment 1121
For those interested in more details, read on. For others, I am basically just asking if it is code compliant to install a female plug and male plug in home wiring between the panel and the loads served by the wire (female plug goes to panel) as shown in the first picture. The reason to do this would be to allow the circuit (male plug) to plug directly into a generator or all-in-one solar system, bypassing the panel. The panel picture is just so you know what my US 200A 120V split phase panel looks like in case that helps.

More details...

If a generator (whether it be a gas powered generator or all-in-one solar/battery system) has a 15A or 20A circuit breaker built-in it seems to me this would be safe, but I am not a trained electrician. Installing plugs would not be as easy for panels in finished areas where wires are behind a wall, or for conduit protected wires, but for panels in unfinished areas like the one pictured (in an unfinished basement) this is a really inexpensive and easy way to get backup or alternative power to appliance circuits.

Pros
Easy to install the plugs in wires if they are not in walls or conduit.
I think it should be fire safe if the off grid supply (generator or solar system) has a breaker the same size or smaller than panel breaker serving that wire.
I think it should be electrician safe if the wires are labeled (on panel side and appliance side of wire).
I think it should be lineman safe because power from the generator completely bypasses the panel so it can not back-feed the grid(mains).
My favorite pro is that this allows other devices to be installed in the utility area where the panel is located instead of taking up space on outlets (things like Killawatt meter, iot smart switches, and RFprotect devices to protect refrigerator from brown outs).
Makes it easier to use all-in-one systems like the Yeti, Bluetti, and others in homes, especially if solar panels are used and the solar wires enter the home in the same area as the electric panel.
Makes it easier and cheaper to connect critical loads to a generator with breaker protected outlets during a power outage.
The male and female plugs are easy to find at most hardware stores, inexpensive, and there are several instruction videos online to show beginners how to safely select and install them.

Cons
May not be easy if wires are behind a finished wall or in solid conduit. If conduit is required, flex might be an option but would make install more difficult for beginners.
The installer must make sure the off grid energy source has a breaker appropriate for the wire.
Others? Is this not code compliant in most or all situations? Could it cause a failed home inspection?

The National Fire Protection Association (NFPA) has a web page that allows submitting questions about US national electric code compliance. This would probably be the most definitive way of answering this question, but only NFPA members or public officials can ask questions.


I may eventually look into joining the NFPA just to ask about this, but for now thought I would run it past the DIY Solar Forum to see what people think. Maybe someone on the forum is an NFPA member?

In the US there is a youth education program called 4-H that is associated with University Extension. 4-H offers youth electrical safety classes where electricians teach kids electrical safety with hands-on activities. One of the hands-on activities is to help the kids make extension cords using a wire, male and female plug ends, wire strippers, and a Phillips screwdriver. They teach the kids that small lamp cords should not be used for space heaters. They also teach them how to pay attention to cord size and device power use labels so they don't plug too many high draw appliances into one power strip. These classes are not available to all kids, and some kids forget what they learn (according to follow up surveys). I mention this to make the point that safely plugging in cords and understanding how to determine appliance usage is really the entry point of safely using electricity. If batteries continue to fall in price and all-in-one systems with breakers that match up with common home circuit sizes become more common this approach of using home wires as extension cords might help a lot of people safely and cheaply install solar even if they know only the basics of electrical safety and have a limited budget. I think it could possibly lead to quicker adoption of solar by making it more “plug and play”, but if it is not code compliant that will hold it back even if it can be done safely.
This is NOT NFPA 70 NEC compliant in any way. This thread should be deleted from this forum !
 
I have never heard of a time limit on the use of a flexible cord or cable. Please reference the NEC article that addresses such a condition so that I may read up on that. Thanks.
Correct please cite the NEC Article that puts a time limit on extension cords, I have a 2020 and 2014 Code books handy. No its not legal but for other reasons. If there was a 90 minute limit on extension cords a lot of job sites would be in trouble!!
 
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Correct please cite the NEC Article that puts a time limit on extension cords, I have a 2020 and 2014 Code books handy. No its not legal but for other reasons. If there was a 90 minute limit on extension cords a lot of job sites would be in trouble!!
I responded in the post below that one, it is 90 DAYS for decorative lighting, not minutes. Cords must not be used as permanent wiring. If needed longer than 90 days, permanent wiring must be installed.
NEC 400.7

NEC 400.8 states that any equipment connecting to an extension cord longer than 30Days should have permanent wiring installed.

Also, that while not IN USE the cords should be unplugged.

 
I responded in the post below that one, it is 90 DAYS for decorative lighting, not minutes. Cords must not be used as permanent wiring. If needed longer than 90 days, permanent wiring must be installed.
NEC 400.7

NEC 400.8 states that any equipment connecting to an extension cord longer than 30Days should have permanent wiring installed.

Also, that while not IN USE the cords should be unplugged.

My 2014 shows 400.7 as detailing Uses for flexible cords, 400.8 Uses not Permitted. and of course its never a replacement for permanent wiring. So was the "longer than 90 days" added as its not in the 2014?
OK in Article 590.3 B Limit on 90 Days for decorative lighting but for temporary construction as long as needed.
 
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My 2014 shows 400.7 as detailing Uses for flexible cords, 400.8 Uses not Permitted. and of course its never a replacement for permanent wiring. So was the "longer than 90 days" added as its not in the 2014?
OK in Article 590.3 B Limit on 90 Days for decorative lighting but for temporary construction as long as needed.
You can view the current NEC 2020 edition at
(after setting up a no cost account/login ID):
 
That's totally cool.

Creativity is what makes this solar hobby fun.

About these codes. I don't care about code.

Electricity does not give a crap about some stupid code if my plug is either 16 inches off the floor (code) or 4 feet off the floor next to the recliner so I don't have to hunch down and dig behind furniture to plug in this laptop.

There is really only two possible conditions with electrical. Its either safe or its not.

Yours looks awesome.

Meanwhile in houses everywhere...



1661896719216.png
 
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I guess you don't care about burning your house down or getting electrocuted either. This thread made me think about how safe something I do really is. Every winter I hook up a timer to an extension cord to a radiant heater in my van so when I go outside my van's windows are clean and ice free. Four hours doing this or my windows are solid ice. I also put a sheet across the windshield. the mickey mouse part of this is that I drilled a hole through the wall and put a short heavy duty cord through the wall that the extension cord plugs into. I have this connection covered to keep snow and water out. I did have to replace the extension cord, it got old and started to come apart. I've done this for a couple of years. I think this is 750 watts. I was never really happy with this setup. But it works. For a home build in walls, I would just buy the right wire.
 
My eyes physically hurt after looking at this picture.

The only one who will like or agree to this type of install is your insurance adjuster, after he denies your claim.
 
Going back to the first picture in the original post, The OP has a good reason to do what he did in dealing with power outages. Would it not satisfy code if you wired in a box with a female outlet on each wire coming out of the panel and then wired in a box with a cabtire pig tale coming out of it and the male plug on the end to plug into the outlet. Should that not be code compliant?
 
The OPs design is actually quite brilliant. Thats how it was done.

1662281280305.png1662282863957.png



I am doing the same thing in my system but won't be using 120vac plugs because I am making the PV inputs switchable so using MC4s.

My array 7s3p. Sometimes I may want all 3 of the 7s into either my 32 volt or 12 volt charge controllers or 2 strings charging the 12 volt bank and 1 string charging the 32 volt bank or vice versa.
 
Going back to the first picture in the original post, The OP has a good reason to do what he did in dealing with power outages. Would it not satisfy code if you wired in a box with a female outlet on each wire coming out of the panel and then wired in a box with a cabtire pig tale coming out of it and the male plug on the end to plug into the outlet. Should that not be code compliant?

Its more like a secret code, no one knows.

Electrical receptacle outlets on branch circuits of 30 amperes or less and communication system receptacles shall be located no more than 48 inches (1219 mm) measured from the top of the receptacle outlet box nor less than 15 inches (381 mm) measured from the bottom of the receptacle outlet box to the level of the finished floor or working platform. If the reach is over a physical barrier or an obstruction (for example, a kitchen base cabinet), receptacles shall be located within the reach ranges specified in Section 1138A.3. Physical barriers and obstructions shall not extend more than 25 inches (635 mm) from the wall beneath the receptacle.

Receptacle outlets that do not satisfy these specifications are acceptable provided that comparable receptacle outlets, that perform the same functions, are provided within the same area and are accessible.


On the wall that is 11 feet long, without the door, the code requires 1 electrical receptacle (outlet) as that receptacle (outlet) is no more than 6 feet from either perpendicular wall.

On the opposite wall there is a doorway in the center of the wall. The code requires that we have an electrical receptacle (outlet) no more than 6 feet from the corner of the wall and no more than 6 feet from an obstruction - the doorway.

WHAT ?

No wonder housing prices are insane !

Or

"I've come across properties in which the County Records match the advertised bedroom Count but one of the designated bedrooms doesn't have a closet. If a house was built in the last 20 years, and if the county records match the advertised number of bedroom, I would consider installing a closet or verifying the septic tank size. It could be that the septic is the correct size for the advertised bedrooms, but it could also be that the wrong size septic was installed and not corrected in the records. "

Oh Please ! Split hairs over a closet and a few hangers, can't we just live our lives already ??
 
Just a heads up, that will not pass any code anywhere for the reasons other people mentioned. That situation is dangerous for many reasons listed above. I am not the electrical police but a couple of things to keep in mind. it may have worked over the years and possibly because they are not pulling heavy loads. Probably the single most important aspect, besides safety for you and your family in the case of failure, is if something were to happen, no insurance company will honor the claim. Fire would be the direct result of failure, and if a fire was started or believed to be started at that point no insurance company would not be liable to pay out that claim, so you would be out of a house, responsible for damage to your property and any property associated with that damage and no money will come from any insurance company. In conclusion, even if you believe your theory is sound, the law and the courts would not side with you. You can possibly lose everything and be liable for damage and harm to anyone affected by the said failure. Please take the proper steps to fix and protect yourself.
 
Regardless if this application complies with the NFPA 70 (NEC), you better not let your homeowner's insurance underwriter or agent see it. Your rates might go up a bit. Oh, you do have insurance, right?

As far as code violations, an obvious #1 is lack of being fastened within 12" of the enclosure NFPA 70, 334.30.

#2 is that NM (Romex) type wire is not considered to be a "flexible" cable assembly per NFPA 70, Table 400.4 This table contains all of the listed flexible cable types. You will not see type NM wire listed here which means cord caps that are listed for installation on flexible cable assemblies are not allowed to be installed on type NM. NM cable does not have thick enough outer insulation to resist damage of the individual conductor insulation from the strain relief clamp or to resist other types of physical damage to the conductors. Additionally, NM is made up of solid conductors which are not generally flexible nor do they hold securely under a clamp within a cord cap termination point. True flexible cable assemblies are made with stranded conductors.
 
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"It is easy and inexpensive to make home wiring into extension cords!"

I do it all the time. (Romex or UF with plug & socket, separate not part of home wiring.)
Some of these even have wet in-use boxes & covers. Plugged into GFCI outlets I'm perfectly comfortable using them.

I also have a roll of UF with MC connectors and a DC rated switch. That serves as PV extension cord from combiner box to garage, for testing inverters before they're installed. (Dryer cord to connect inverter's AC terminals to house.)
 
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