Dc inverter power feedback into home


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Old 06-16-14, 01:20 PM
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Dc inverter power feedback into home

Hello guys, I'm new to this forum. I have a question about some inverter wiring needs.
I have a ups inverter, which means it has an AC input and an AC output.
Input is for battery charging and current sensing (mains). Output is for providing AC feed when the mains suffer a blackout.

I need my inverter to provide power to my entire home (barring some high usage equipment), but I'm not sure how I can connect the input and output lines to the same power outlet in the house without creating a big problem for the inverter since power will flow from the house to the inverter when mains power is present.
How can I stop the power from flowing back into the inverter when mains power is present.
I want a somewhat automated solution, not needing me to switch on and off a few switches to get the inverter hooked up every time there is a blackout.

Thanks for the help guys. Sorry for the long post
 
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Old 06-16-14, 01:24 PM
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A transfer switch or comparable mechanism to prevent both utility power and inverter power from feeding the home at the same time is mandatory.

Transfer switches specifically to handle this situation are common standard pieces of equipment.

A transfer switch intended to select the power supply for the entire house is installed at the main panel or upstream (before it).

You can get automatic transfer switches although they are not cheap.

Power from an alternate source may never be infused into the home electrical system via one of the receptacles, where it is possible although not intended that the utility power lines remain switched in.
 
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Old 06-16-14, 01:41 PM
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Welcome to the forums.

What size is the inverter ?
Connecting an inverter into home wiring is not an easy job and most inverters aren't large enough to be switched into the home automatically without shedding a lot of load.
 
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Old 06-16-14, 02:21 PM
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pjmax, is a 500w modified sine wave inverter with charge and ups function. All I need to have running during the blackout are the normal lighting fixtures (all minimal CFL bulbs) and a wall fan for the hot days. I did a test during the last power outage and everything went great. Except I had to manually switch off mains source just in case the power suddenly Comes back.
 
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Old 06-16-14, 02:24 PM
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AllanJ, could you kindly show me a link of a transfer switch. Thanks
I'm not sure I understand what you mean by your last paragraph. Do you mean that utility power may be present safely with inverter connected?

Regarding infusing power into the grid, that's already done with grid tie inverters, so there is a mechanism that exists to make utility power and home generated power work on the same lines simultaneously. But I can't use that at home cause I don't think the power company supports that, and I currently do not get my power from a renewable source.
 
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Old 06-16-14, 04:04 PM
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For what you want to use better to use 12 volt DC versions. Simpler cheaper more efficient.
 
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Old 06-16-14, 10:50 PM
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Use a 12v version of what? Sorry I don't follow..
 
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Old 06-16-14, 11:36 PM
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Use a 12v version of what? Sorry I don't follow.
You wrote:
All I need to have running during the blackout are the normal lighting fixtures (all minimal CFL bulbs) and a wall fan for the hot days.
.
 
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Old 06-17-14, 02:52 AM
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If you mean i should install 12v lights, then this is not what i need. I need my house lights on when there is a blackout. Normal room lights, not emergency lights.
 
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Old 06-17-14, 03:38 AM
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I need my house lights on when there is a blackout
Why, you'll get about the same light.
 
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Old 06-19-14, 01:41 AM
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well, thats my requirements. i dont want to go into a new project of installing stuff all over the house with messy wiring.
 
 

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