Inverter to Wall Outlets

[mitchk]

I am wondering about AC wiring to wall outlets. I have a 1200W inverter with 2 outlet plugs and no option to hard wire 120 AC to my 4 desired wall outlets. I am completely new to electrical stuff and I want to make sure I have it planned out correctly before purchasing the material I need.

1. Is there a good way to go from the 2 inverter outlets to my 4 wall outlets. Is it as simple as running extension cords through the wall and splicing/ wiring each cord to 2 outlets?

2. Is there specific AC cable I need to get? Do I need to be careful to not accidentally buy DC cable? The reason I am confused is because I read that I would want 12/2 cable since I am running single phase 120V. However sometimes when I look up 12/2 I see just a hot and a nuetral or ground wire. Other times 12/2 means three wires (hot, neutral, and ground). I bought 12/3 wire off of amazon which is 3 wires (hot, neutral, and ground). Is that 12/3 just labeled wrong and should be 12/2 or am I misunderstanding something? It seems like when discussing DC 12/2 is 2 cables and when discussing AC 12/2 is 3 cables. This makes me wonder if the 12/3 I bought is actually for DC and I shouldn't use it for AC.

3. Stranded cable is preferred for both AC and DC applications within a moving vehicle, is that correct?

4. If I go with 2 plug outlets at each of my 4 desired locations is it fine to run one 12/2 cable and splice it at outlet to both plugs? I know I will only be able to run each outlet at 10A if they are both plugged in. Is there any issues with doing it this way?

Sorry for the long post! Hopefully I will continue to gain a better understanding of both AC and DC wiring.

[Danjo]

I am not a licensed electrician, so this is what I would do. You might do something else. You’ll need to size the conduit and j-boxes to code.

Can you post the manual for your inverter?

A lot of people would run Romex non-metallic cable, but without having more info about what you’re installing into, it’s safer to say Your wire run needs to be protected from damage. This is accomplished by enclosing the wire in an armored raceway such as EMT or FMT conduit. What I would do, would get a junction box which I would mount next to your inverter. I would get a 12/2 extension cord to plug into the inverter outlet and clamp that to the box, then use FMT to run to Junction boxes for the outlets. outlets, pulling 12 gauge stranded THHN wire, white, black, green.

Your run can be one string. All splices happen in the junction boxes using wire nuts of the correct size. All metal parts need to be bonded to ground.

You want to keep polarity correct throughout your circuit extension, meaning white to white and black to black throughout. Keep this in mind with your extension cord adapter as well

[mitchk]

Originally Posted by Danjo

I am not a licensed electrician, so this is what I would do. You might do something else. You’ll need to size the conduit and j-boxes to code.

Can you post the manual for your inverter?

A lot of people would run Romex non-metallic cable, but without having more info about what you’re installing into, it’s safer to say Your wire run needs to be protected from damage. This is accomplished by enclosing the wire in an armored raceway such as EMT or FMT conduit. What I would do, would get a junction box which I would mount next to your inverter. I would get a 12/2 extension cord to plug into the inverter outlet and clamp that to the box, then use FMT to run to Junction boxes for the outlets. outlets, pulling 12 gauge stranded THHN wire, white, black, green.

Your run can be one string. All splices happen in the junction boxes using wire nuts of the correct size. All metal parts need to be bonded to ground.

You want to keep polarity correct throughout your circuit extension, meaning white to white and black to black throughout. Keep this in mind with your extension cord adapter as well

Thank you for the information that was very helpful! I bought a 1200W AIG pure sine wave inverter by Giandel. Here is a link to the manual. PS-1200JCR USER MANUAL 19.4 - Giandel. So I guess I would only need to wire one outlet from the the inverter to the Junction box since one outlet has the capability to produce all 1200W that the inverter is rated for. According to the Amazon page the inverter is protected by 30A fuses which would be much higher then 1200W.

So you are saying that all 4 of my outlets could be wired to one circuit? I guess it doesn't matter since my max is 1200W whether I am using one outlet or all 4 right?

I will look into getting some 12/2 FMT cable although I am still a little confused on if that will be 2 strands or 3. I think for AC it is supposed to be 3 (hot, neutral, ground)?

[Danjo]

Originally Posted by mitchk

Thank you for the information that was very helpful! I bought a 1200W AIG pure sine wave inverter by Giandel. Here is a link to the manual. PS-1200JCR USER MANUAL 19.4 - Giandel. So I guess I would only need to wire one outlet from the the inverter to the Junction box since one outlet has the capability to produce all 1200W that the inverter is rated for. According to the Amazon page the inverter is protected by 30A fuses which would be much higher then 1200W.

So you are saying that all 4 of my outlets could be wired to one circuit? I guess it doesn't matter since my max is 1200W whether I am using one outlet or all 4 right?

I will look into getting some 12/2 FMT cable although I am still a little confused on if that will be 2 strands or 3. I think for AC it is supposed to be 3 (hot, neutral, ground)?

Last night I wasn’t thinking about your expectations so just to be clear, the most you can pull off this inverter is 10A total. You can have as many outlets as you like, but 10A is the limit.

I looked at the manual to see if the two outlets are independent circuits. It doesn’t say and I can’t tell from the diagrams. I suspect it’s one circuit. I also do not see any circuit protection in the diagrams or photos. It could be there and I don’t see it.

12 gauge wire is good up to 20A so you won’t be able to overload the wire with this inverter, though it says that it can make 20A peak power, so the 12 gauge wire is smart. You might want to look into the fault protection on this inverter. If it doesn’t have it, a 20A fuse or breaker may be a good idea.

The 2 in 12/2 denotes the number of conductors in the cable, the ground is included, but not a conductor. FMT May come with wires already In it, but usually that would be called MC cable. Unless you can find MC with stranded, you probably want to make your own by buying empty FMT.

[mitchk]

Originally Posted by Danjo

Last night I wasn’t thinking about your expectations so just to be clear, the most you can pull off this inverter is 10A total. You can have as many outlets as you like, but 10A is the limit.

I looked at the manual to see if the two outlets are independent circuits. It doesn’t say and I can’t tell from the diagrams. I suspect it’s one circuit. I also do not see any circuit protection in the diagrams or photos. It could be there and I don’t see it.

12 gauge wire is good up to 20A so you won’t be able to overload the wire with this inverter, though it says that it can make 20A peak power, so the 12 gauge wire is smart. You might want to look into the fault protection on this inverter. If it doesn’t have it, a 20A fuse or breaker may be a good idea.

The 2 in 12/2 denotes the number of conductors in the cable, the ground is included, but not a conductor. FMT May come with wires already In it, but usually that would be called MC cable. Unless you can find MC with stranded, you probably want to make your own by buying empty FMT.

Yeah, I was confused about this 30A fuse that was apparently in the unit but not available on the diagram. Like you said I know I can only pull 10A total but I sized the cable to be able to handle 20A to account for the surge. I have 2 outlets on one side of the bus and 2 on the other side so I might just run two circuits with each circuit supplying to 2 outlets. Although now that I think about it each outlet cover is technically 2 pluggable locations so it would be 4 plug locations per circuit.

I had already bought this 14/3 cable (https://www.amazon.com/gp/product/B0...UTF8&psc=1)but it doesn't include a ground wire so I'm assuming it is basically the same as 12/2 that does include a ground wire except my ground wire has insulation. Does that seem correct to you? I could find empty FMT to put around this cable.

I will also look into adding a 20A fuse right after the inverter in order to protect the internal circuit.

Thanks again for your help!

[ol trunt]

The link you posted at Amazon says the wire is 14/3 not 12/3?? The green wire is the ground wire.
Jack

[mitchk]

Originally Posted by ol trunt

The link you posted at Amazon says the wire is 14/3 not 12/3?? The green wire is the ground wire.
Jack

Yup, I accidentally wrote 12. Meant to say 14. It must just be incorrectly named then since I believe 14/3 should have 3 conductors and a ground.

[mitchk]

Assuming my bus is water tight and that the pathway for the conduit is nice and smooth could I get away with just using wire loom tubing. I'm sure its not as good as the FMT but if it works just as well in my situation I would rather use the wire loom.

[Danjo]

That link is for 14 gauge.

It is permissible to pull NMC through conduit, though I wouldn’t do that as a first choice.

If that’s all one circuit inside the inverter, the you’d only need one connection. I suspect that they put two because they expect you to plug directly. Using one simplifies your fault protection if you decide to add it.

[Danjo]

Originally Posted by mitchk

Assuming my bus is water tight and that the pathway for the conduit is nice and smooth could I get away with just using wire loom tubing. I'm sure its not as good as the FMT but if it works just as well in my situation I would rather use the wire loom.

What is “wire loom tubing”? Are you referring to that plastic stuff that’s split down the length? If you are, there’s not enough protection for “high voltage “ conductors.

[mitchk]

Originally Posted by Danjo

What is “wire loom tubing”? Are you referring to that plastic stuff that’s split down the length? If you are, there’s not enough protection for “high voltage “ conductors.

Yeah its the split plastic stuff. Ok so I could probably use the plastic stuff for 12V and then buy the conduit you were referring to for the 120v stuff.

[mitchk]

Also I think I read somewhere that you want to keep your 12V and 120V circuits separate. Is it fine to place multiple 12V circuits worth of cable in the same conduit?

[JackE]

Originally Posted by mitchk

Also I think I read somewhere that you want to keep your 12V and 120V circuits separate. Is it fine to place multiple 12V circuits worth of cable in the same conduit?

It had better be! When you pull one of the many wiring harnesses out of a bus and realize there are a good 50 wires in it, I don't think there is any problems with it. Unless you get damaged wires touching each other there won't be any problem.

[mitchk]

Originally Posted by JackE

It had better be! When you pull one of the many wiring harnesses out of a bus and realize there are a good 50 wires in it, I don't think there is any problems with it. Unless you get damaged wires touching each other there won't be any problem.

That's what I assumed but I also figured that most of my stuff would be higher amperage then the lighting harnesses and I just wanted to confirm that didn't make a difference.

[Mudhutwarrior]

Biggest issue I have seen is with burnoff at the receptacle. Use Hospital grade plugs for the connection to the inverter. Remember. loose connections and thermal cycling create resistance and heat.
Hospital grade plugs are heavier all around. if vibration is an issue you can tywrap them to the inverter. Might need to add a bracket to accomplish this but worth it.

[Musicforge]

I ran my wiring in BX on first bus thinking it would protect the wiring, but it did not protect the wiring from me. I wont do that again, I had short hard corners to make and the wiring shorted out on the metal casing and I went through two inverters, now all of my wiring goes through hard plastic conduit into plastic boxes and I do not use an inverter since I am running for lack of a better term a power-wall providing 120VDC

[Ranchorossa]

I'm using the same inverter as you. 14/2 wire pulled through PVC conduit. Use PVC fittings to attach conduit to the boxes. Secure the conduit to the floor or whatever you are laying it on every 4' or so. Even the toughest of rides won't jar anything loose. As fast as connecting the Romex to the inverter, I just used a heavy duty commercial plug. Since the circuit will put out no more than a steady 10amps, I put a 15 amp CB in line. I had the Romex just laying around or you can buy three wires and run them through the PVC. Spend the extra couple of bucks and do it right, if not a little better. Good luck.

[JackE]

FWIW, the motor home I am scavenging from had several hundred feet of 12/2 romex throughout it, none of it in conduit. Being sticks and staples, I don't think there were any spots where it was in contact with metal edges. Despite that, I will be running all my wires through pvc conduit. It's cheap and readily available, and insurance against wire rubbing against metal, which there seems too be no shortage of in a bus!