DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

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offgridmainac
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DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by offgridmainac »

Is it mandatory a Mate to operate the GVFX 3648, 120 - 60HZ? - DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?
offgridmainac
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by offgridmainac »

The thing is that where I live my electrical connection is 220 volts ac but using 2 legs of 110 or 120 each, 120+120= 240 VAC.

The issue here is that I ordered a GVFX 3648, 120 vac, 60 HZ With the Mate 3, & the Hub 4. I been thinking... What do I need to turn it in to 240 vac from 120 vac ?
Can I just bridge a jumper over at the electrical distribution box to supply both leg connection having only 120 vac. Do I have to Install a Transformer even If I don't have any needs for 240 volt appliances. I am a little confused on this and I know I will probably end up buying the transformer any way to have 240 VAC but I can't go for it at the moment. Any helps.....
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by gww »

This is my effort to try and answer the question I think you are asking. Are you in the usa. If yes then with one inverter you can only run 110 with one inverter. 240 volt is two legs of 110 volts offset from each other by 90 degrees. Hooking the inverter to both breakers would not give you this. Buying outbacks 240 volt transformer would give you this or buying anouther gvfx and programing them classic master and slave would also give you 240 volts. If you don't have 240 loads you can just move the 110 loads to a dedicated breaker panel and run through the single inverter. If your intention is to sell to the grid you could hook no loads to the inverter and just feed the grid but when the grid goes down you could run nothing. I hope this helps.
gww
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Kurt Lundquist
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by Kurt Lundquist »

If you do not need 240Vac then you do not need the transformer. DO NOT jumper the two hot legs of your electrical panel.

-K
Kurt Lundquist
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offgridmainac
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by offgridmainac »

I got your point on the connection, the problem is that if I do not make a jumper I would have only electricity in half the house panel. Connecting a wire from example leg 1 to leg 2 on the panel will give me only 120 VAC, I understand that, the only thing is that I will not be able to run any 220 Load and of course I should not try to do it neither. I will jump it, I have to But I understand that if I need later on 240 Vac I will have to buy the 500 USD transformer to be able to have that voltage divided 120 vac on each leg.
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Kurt Lundquist
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by Kurt Lundquist »

Without getting into too much detail if you jumper the line you run a serious risk of burning down your house. The neutral wire will have the potential of carrying double the current that it is rated for.

Your four options as I see it:
Move all your breakers/circuits to the hot leg of the panel
Replace the panel with a 120 volt panel
Install a transformer for 120/240 output
Install a second inverter for 120/240 output

Putting a jumper between the two hot legs is a really bad idea.
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by SumPowerRays »

kelseyradley wrote: Thu Sep 14, 2023 8:11 pm I understand the connection, however if I do not make a jumper, I would only have power in half of the home panel. I am aware that connecting a wire from leg 1 of the panel's example to leg 2 will only give me 120 VAC; nonetheless, I will not be able to run any 220 loads, and I should, of course, avoid attempting to do so. I must jump it, so I will, but I am aware that if I require 240 Vac in the future, I will need to spend $500 on a transformer so that I can divide that power into 120 Vac for each leg. cookie clicker
I would suggest you contact your installer or a licensed electrician before you try this. You could be getting yourself into more trouble than you want with this. It is not accepted practice to connect both bus bars in your house panel to the same 120 volt source.
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Re: DO I NEED A TRANSFORMER TO MAKE IT BE 240 VAC (2) HOT LEGS?

Post by ralphday224 »

I think the only problem would be where there are 120v outlets on double pole breakers...kitchen split receptacles. I have my home service panel "jumpered" so both sides are 120v. No 240volt loads. The kitchen outlets breakers are moved so both legs feed off the same bus and a kiddie proofing plastic plug is put in one of the two outlets so only one 120v 15amp load can be applied to the breaker, and hence the neutral.

20 years ago it was standard practice to make your whole house panel 120v. I do have a 240 volt load, a heat pump, but it is runn off an autotransformer (xantrex) which feeds from a 120v circuit. Again, standard practice 20 years ago when I started out.

Ralph
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