Basic wiring connection to/ from inverter

[dawgleader1]

Hey guys & gals. I have a very basic, stupid question I hope I'm not drummed out of here for. I have a MPP solar 6048 inverter, I originally had a Growatt 3000tl but decided that I wanted/ needed something bigger so please ignore that in the picture, I won't be connecting that. I will be completely off-grid with this system, not connected directly to the grid or my home's system, I'm using it purely as an emergency/ back-up power system for storms, and of course the zombie apocalypse. I'd like to connect a power cord to the AC input so that I can plug this into one of my home's regular AC electric plugs in the garage. This will allow me to charge up the batteries and keep them topped off in the case of a power loss. Once the batteries are full, I'll unplug it and re-plug it as needed to keep the batteries full but I won't be leaving it plugged in 24/7 after I'm charged up. Then I'd like to connect a power cord/ surge protector outlet to the AC out on the inverter to plug in my things, such as my freezers and such when needed. I also have a 12 panel, 4000w solar panel array but I'm not ready to connect that yet. The panels have been mounted but I haven't connected any wiring yet so that will be a project for later. I just want to get the batteries and inverter set up so that I'm ready for the upcoming winter, so we're not **** out of luck with an ice storm. The 6048 inverter is connected to 2x all-in-one 10kwh/ 48v battery packs for 20kwh storage. My problem is the power cords for AC outlet connection in and AC surge protector out are 3-wires and the AC input and output is 4 connections. I know it probably sounds like I'm a moron but what's my play here? Do I just connect the 3 to 3 and leave 1 empty? Also, as a side question, in this scenario, since the house outlet is grounded, I won't need to ground the inverter/ batteries again, correct? For some reason it won't let me attach pictures but ask any questions. Any advice is greatly appreciated. I can also take criticism if I'm completely crazy or something is way off. I'm looking forward to hearing from anyone willing to help. Thanks in advance.

[bcroe]

The last ice storm here coated the panels, with some snow on
top output dropped to near zero. I had to wait for the next weather
around freezing or higher (weeks) before the ice could be removed
with no damage. No batteries could deal with that time interval. I
was not worried, because the backup generator was available,
though it has not been used this century.

Putting all those panels on backup service only, means that most
of the energy they potentially generate will be lost. All my panel
energy is either used, or credited by net metering for later use.

Bruce Roe

[Bala]

Hey guys & gals. I have a very basic, stupid question I hope I'm not drummed out of here for. I have a MPP solar 6048 inverter, I originally had a Growatt 3000tl but decided that I wanted/ needed something bigger so please ignore that in the picture, I won't be connecting that. I will be completely off-grid with this system, not connected directly to the grid or my home's system, I'm using it purely as an emergency/ back-up power system for storms, and of course the zombie apocalypse. I'd like to connect a power cord to the AC input so that I can plug this into one of my home's regular AC electric plugs in the garage. This will allow me to charge up the batteries and keep them topped off in the case of a power loss. Once the batteries are full, I'll unplug it and re-plug it as needed to keep the batteries full but I won't be leaving it plugged in 24/7 after I'm charged up. Then I'd like to connect a power cord/ surge protector outlet to the AC out on the inverter to plug in my things, such as my freezers and such when needed. I also have a 12 panel, 4000w solar panel array but I'm not ready to connect that yet. The panels have been mounted but I haven't connected any wiring yet so that will be a project for later. I just want to get the batteries and inverter set up so that I'm ready for the upcoming winter, so we're not **** out of luck with an ice storm. The 6048 inverter is connected to 2x all-in-one 10kwh/ 48v battery packs for 20kwh storage. My problem is the power cords for AC outlet connection in and AC surge protector out are 3-wires and the AC input and output is 4 connections. I know it probably sounds like I'm a moron but what's my play here? Do I just connect the 3 to 3 and leave 1 empty? Also, as a side question, in this scenario, since the house outlet is grounded, I won't need to ground the inverter/ batteries again, correct? For some reason it won't let me attach pictures but ask any questions. Any advice is greatly appreciated. I can also take criticism if I'm completely crazy or something is way off. I'm looking forward to hearing from anyone willing to help. Thanks in advance.

The questions you have asked that I have highlighted are not something that anyone should answer. If someone does you have no way of knowing if it is correct so should not follow their advice.

You need to get a qualified electrician to sort it out.

[Mike 134]

The questions you have asked that I have highlighted are not something that anyone should answer. If someone does you have no way of knowing if it is correct so should not follow their advice.

You need to get a qualified electrician to sort it out.

What could possibly go wrong? Taking electrical advice from a stranger on the internet is no more dangerous than getting medical advice from a stranger on a medical forum.

[dawgleader1]

Hey bcroe, thanks for jumping on the thread. I'm not really sure what you were talking about but thanks. I don't see how your snow story guides me or offers any help, or that it even pertains to my post at all. But thanks for the story.

Bala, also, thanks to you as well. However, you didn't really offer any more help than bc's snow story did. I figured the idea of these forums were to share ideas and for stupid newbies like myself to look for help, advice, and guidance from more experienced pros like yourself and others. What I'm asking doesn't seem like a very huge or involved scenario. I'm not asking you to walk me through how to wire a transfer box to my house and the electric grid or something difficult like that. It seemed a basic question about wiring 3 wires to an inverter with 4 connections that I wasn't sure about. I figured out of all the big brains on here someone would have some help to offer. But thanks for your warning, in essence 'go pay someone, I'm not going to help you and no one else should either'.

Mike, once again, thanks for the post. Once again, not very helpful but thanks anyway for contributing. I guess more helpful than the other 2 since your point was well put.

I was hoping for a little more help than a snow story and someone telling me they aren't going to offer advice, to go pay someone.

Does anyone have any helpful advice or input? If not, I guess I'll try some other platforms or forums.

Thanks...

[Bala]

You're asking not only about basic? wiring but also about grounding.

There are 4 wires, is it a single phase or 3 phase inverter.

When safety is considered with A/C mains power there is nothing simple about it. Earthing/grounding/MEN/Rcd/2power sources are terms that need to be understood correctly if the system is to be safe.

You can wire it and it may work, but be unsafe.

Your question is not basic, which is why i suggested getting a qualified electrician.

[Mike 134]

Hey bcroe, thanks for jumping on the thread. I'm not really sure what you were talking about but thanks. I don't see how your snow story guides me or offers any help, or that it even pertains to my post at all. But thanks for the story.

Bala, also, thanks to you as well. However, you didn't really offer any more help than bc's snow story did. I figured the idea of these forums were to share ideas and for stupid newbies like myself to look for help, advice, and guidance from more experienced pros like yourself and others. What I'm asking doesn't seem like a very huge or involved scenario. I'm not asking you to walk me through how to wire a transfer box to my house and the electric grid or something difficult like that. It seemed a basic question about wiring 3 wires to an inverter with 4 connections that I wasn't sure about. I figured out of all the big brains on here someone would have some help to offer. But thanks for your warning, in essence 'go pay someone, I'm not going to help you and no one else should either'.

Mike, once again, thanks for the post. Once again, not very helpful but thanks anyway for contributing. I guess more helpful than the other 2 since your point was well put.

I was hoping for a little more help than a snow story and someone telling me they aren't going to offer advice, to go pay someone.

Does anyone have any helpful advice or input? If not, I guess I'll try some other platforms or forums.

Thanks...

I went to their website and looked at the wiring instructions and as you say it is basic wiring. Two caveats, one I am an Electrician and two, if it doesn't make sense to you than perhaps it's not in your wheelhouse to tackle.

[SunEagle]

I went to their website and looked at the wiring instructions and as you say it is basic wiring. Two caveats, one I am an Electrician and two, if it doesn't make sense to you than perhaps it's not in your wheelhouse to tackle.

+1 good advice

[bcroe]

Hey bcroe, thanks for jumping on the thread. I'm not really sure what you were talking about but thanks. I don't see how your snow story guides me or offers any help, or that it even pertains to my post at all.

You said
so we're not **** out of luck with an ice storm.

My point, you WOULD be out of luck relying on solar and batteries.
Bruce Roe

[dawgleader1]

First off, I want to apologize if I'm coming across as an ass. I'm not trying to be rude, just trying to get some advice. I'm not going to sue anyone and I know that I have to verify anything on the internet as it's not always correct.

Bala, ok, yes safety is of utmost importance but even being a moron with this stuff compared to others on here it still seems straight forward advise. But once again, thanks.

Mike, your being an electrician will obviously provide different eyes on what's basic and what I may see the same way. I've tried to attach a quick sketch of what I think I need to do and some pictures of my setup but for some reason I can't link any pictures to this website so I've typed it up. If you have a chance to glance at it and just say yes or no that would be a big help. If not, then ok and thanks to you as well.

Sun, I agree, good advice. But I'm still trying to get some guidance.

bcroe, I see where you're coming from now. However, I said in my post that I WON'T be using solar panels this year, that's a later project. What I'm trying to do now is just get everything charged up and ready for this winter season so if we get snow and lose power, we have a backup source of electricity. So, snow this year on solar panels isn't a concern.

I'm going to try to clarify

So, my plan:

This is a 240v split phase inverter, maybe I should have mentioned that before. It has AC inputs marked ground, L1, L2, and N. It has the same listed for AC output. Again, I'm wanting to run an extension power cord into the AC input so I can plug into my garage wall outlet to charge up my batteries and a power cord on the AC output so I can connect my freezers and appliances in the case of a bad snowstorm. I'm not directly wiring anything to my home, appliances, or electric panel. Once it's all charged up I will unplug it, it will not be connected 24/7.

So, for the output I would take a cut and stripped 3-wire extension cord and connect the wires to ground-green (the symbol on the left)/ L1- black/ N- white, leaving the L2 spot completely empty. That would give me the 120v output I need for my AC output for a plug to plug my freezers into. I believe since it is a split phase, 240v I could also connect a second cord in the same fashion but with ground/ L2/ N making sure I don't cross the L1 & L2. That would provide me a 2nd set of plug to use but I'm not expecting to need or want to do that.

As far as the input is concerned, I would take an extension cord, cut it and then attach the 3-wire stripped extension cord to the ground-green (the symbol on the left)/ L1-black/ N-white. Because it's a split phase, 240v I believe I'd need to bridge the L1 & L2 for the input so then I'd use a single 12awg wire for the bridge, only running from the L1 to L2. So in this scenario, I'd have 1 wire in the ground and N from the stripped extension cord, 2 wires in the L1 (1 from the extension cord and 1 from the bridge), and 1 wire in the L2 from the bridge.

Does this make sense? If not, that's the best I can do without being able to attach pictures. Hopefully this will clarify what's in my head. Thank you.

[SunEagle]

First off, I want to apologize if I'm coming across as an ass. I'm not trying to be rude, just trying to get some advice. I'm not going to sue anyone and I know that I have to verify anything on the internet as it's not always correct.

Bala, ok, yes safety is of utmost importance but even being a moron with this stuff compared to others on here it still seems straight forward advise. But once again, thanks.

Mike, your being an electrician will obviously provide different eyes on what's basic and what I may see the same way. I've tried to attach a quick sketch of what I think I need to do and some pictures of my setup but for some reason I can't link any pictures to this website so I've typed it up. If you have a chance to glance at it and just say yes or no that would be a big help. If not, then ok and thanks to you as well.

Sun, I agree, good advice. But I'm still trying to get some guidance.

bcroe, I see where you're coming from now. However, I said in my post that I WON'T be using solar panels this year, that's a later project. What I'm trying to do now is just get everything charged up and ready for this winter season so if we get snow and lose power, we have a backup source of electricity. So, snow this year on solar panels isn't a concern.

I'm going to try to clarify

So, my plan:

This is a 240v split phase inverter, maybe I should have mentioned that before. It has AC inputs marked ground, L1, L2, and N. It has the same listed for AC output. Again, I'm wanting to run an extension power cord into the AC input so I can plug into my garage wall outlet to charge up my batteries and a power cord on the AC output so I can connect my freezers and appliances in the case of a bad snowstorm. I'm not directly wiring anything to my home, appliances, or electric panel. Once it's all charged up I will unplug it, it will not be connected 24/7.

So, for the output I would take a cut and stripped 3-wire extension cord and connect the wires to ground-green (the symbol on the left)/ L1- black/ N- white, leaving the L2 spot completely empty. That would give me the 120v output I need for my AC output for a plug to plug my freezers into. I believe since it is a split phase, 240v I could also connect a second cord in the same fashion but with ground/ L2/ N making sure I don't cross the L1 & L2. That would provide me a 2nd set of plug to use but I'm not expecting to need or want to do that.

As far as the input is concerned, I would take an extension cord, cut it and then attach the 3-wire stripped extension cord to the ground-green (the symbol on the left)/ L1-black/ N-white. Because it's a split phase, 240v I believe I'd need to bridge the L1 & L2 for the input so then I'd use a single 12awg wire for the bridge, only running from the L1 to L2. So in this scenario, I'd have 1 wire in the ground and N from the stripped extension cord, 2 wires in the L1 (1 from the extension cord and 1 from the bridge), and 1 wire in the L2 from the bridge.

Does this make sense? If not, that's the best I can do without being able to attach pictures. Hopefully this will clarify what's in my head. Thank you.

IMO any use of an "extension" cord can be dangerous. Also feeding power back into a receptacle that is not dedicated to solar can cause an over current situation without they correct over current protection. Just my 2 cents but again a DIY job can be safe if all codes and regulations are followed.

[dawgleader1]

Hey Suneagle, yes, I agree, using a cut down extension cord for a non-intended purpose can potentially be dangerous. That's why I'm trying to get some advice here. However, if I'm using a proper gauge cord, and attaching the wires in the correct way, I don't think it's too much of a situation, especially for my limited usage. If I was going to use this as a permanent, long-term solution and have the inverter/ batteries connected at all times and/or have my freezers connected all the time, then I would look at it differently and probably hire someone to do it for me. But for me, this is just a stopgap so I can get the batteries charged up for a store outage.

If you could please clarify what you mean by the "feeding power back into a receptacle " part of your comment. I don't plan on feeding any power into the house wiring/ outlets at all. I will have 1 adapted extension cord plugged into an outlet in my garage wired to the AC input to charge my batteries and 1 adapted extension cord wired into the AC output to plug my freezer/ appliances into in the case of a power outage. I will only have the AC plugged into the garage wall outlet to charge the batteries; I will unplug it once they are fully charged. It will not be plugged in 24/7, I'm just trying to get the batteries charged up as a battery back up in case of a bad weather storm until I can get all my solar panels connected. But I won't be able to get the solar array done until probably next year. I would expect the inverter to keep any power from feeding back from the inverter AC input back into the garage outlet I'm plugged into for charging the batteries. Thanks again.

[SunEagle]

Hey Suneagle, yes, I agree, using a cut down extension cord for a non-intended purpose can potentially be dangerous. That's why I'm trying to get some advice here. However, if I'm using a proper gauge cord, and attaching the wires in the correct way, I don't think it's too much of a situation, especially for my limited usage. If I was going to use this as a permanent, long-term solution and have the inverter/ batteries connected at all times and/or have my freezers connected all the time, then I would look at it differently and probably hire someone to do it for me. But for me, this is just a stopgap so I can get the batteries charged up for a store outage.

If you could please clarify what you mean by the "feeding power back into a receptacle " part of your comment. I don't plan on feeding any power into the house wiring/ outlets at all. I will have 1 adapted extension cord plugged into an outlet in my garage wired to the AC input to charge my batteries and 1 adapted extension cord wired into the AC output to plug my freezer/ appliances into in the case of a power outage. I will only have the AC plugged into the garage wall outlet to charge the batteries; I will unplug it once they are fully charged. It will not be plugged in 24/7, I'm just trying to get the batteries charged up as a battery back up in case of a bad weather storm until I can get all my solar panels connected. But I won't be able to get the solar array done until probably next year. I would expect the inverter to keep any power from feeding back from the inverter AC input back into the garage outlet I'm plugged into for charging the batteries. Thanks again.

Sounds better now that you have explained how you plan on using the power connection.

There have been quite a few people on this forum that would like to use a home receptacle to accept power from micro inverters or an illegal inverter to provide power to the home. I keep trying to tell them that even though those "inverters" are sold in the US they are illegal to use unless the receptacle is dedicated to the solar installation and not just an outlet in the home.

As long as you understand that any extension cord is considered temporary and will be removed or replaced by a permanent installation I have no issue with what you are doing. I like to make sure people learn to respect electricity and do things safely or per code.

I hope that explains my concern to you.