How do I connect inverter to AC breaker box?

cupcake · December 2013

Greetings from the desert everyone.

I have a question - does anyone know the answer?

1) How to I hook up a power inverter to a standard AC breaker-box/panel (square D 100amp)

I see there are inverters out there with an hardwire 'AC out' feature that will allow me to run wire from the inverter to the ac breaker box.
Can anyone recommend a brand of inverter and a method of configuring it? (or share some pics of their own set up..)

2) HOW DO I GROUND the system PROPERLY once the inverter is going to the breaker box?

I've read alot on this forum and others about this and I am a bit confused about wheather or not to 'bond' the ground and neutral inside the breaker box, or NOT to bond it because that apparently happens in [some] inverters.

Can anyone clear up the confusion about the grounding all of this?

Im looking to run just lights and other low-watt appliances at a cabin, but have it connected more 'proper' by linking it to a standard AC breaker box and running 'proper' circuits/receptacles from there...

Thank you, and please talk to me like I am in 1st grade.

--CC

westbranch · December 2013

Re: How do I connect inverter to AC breaker box?

The answer to #2 will be as outlined in the installation instructions published by the manufacturer.

The answer to #1 depends on which AC distribution box you are talking about. It can NOT be to present one that supplies power to your house. You will need a separate box for the Inverter circuits and possibly a transfer switch. You need to supply us more information.

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

Wn

westbranch wrote: »

The answer to #2 will be as outlined in the installation instructions published by the manufacturer.

The answer to #1 depends on which AC distribution box you are talking about. It can NOT be to present one that supplies power to your house. You will need a separate box for the Inverter circuits and possibly a transfer switch. You need to supply us more information.

There's no grid power..

The ac dist box is a basic square d brand box you get at home depot...

100 amp 8 spaces ... basic...

I get that you run hot from.inverter to the hot bus in the breaker box...

What about neutral and grounding?
Or is it just like you said..that I should just read the instructions provided with the inverter?

Lastly do you have a favorite inverter you suggest for my setup...

Again I don't plan to ever pull more than 200 watts at any one moment..

No draw at night(I'll shut down inverter each nite)

And its sunny every day here...no clouds ever

Thanks again

C kakes

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

FOrgive me for making this test post, it seems as if this forum puts the newest post on TOP of the page...(testing)

westbranch · December 2013

Re: How do I connect inverter to AC breaker box?

you can show it either way, I use the 'show on top/newest post on top' option. When you hit "New Posts " (top left of dark Blue bar), it will take you to the last read post +1...

OK so no grid, , once you choose an inverter it will explain how to connect....generally though a TSW inverter will need to be connected , in one place to the ground buss in the Dist box. The D-box will thus need to be grounded. And MSW inverters, generally are not grounded unless specified by manufacturer.

What do you want to run with the inverter? this has a bearing on which type is best suited.

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

westbranch wrote: »

you can show it either way, I use the 'show on top/newest post on top' option. When you hit "New Posts " (top left of dark Blue bar), it will take you to the last read post +1...

OK so no grid, , once you choose an inverter it will explain how to connect....generally though a TSW inverter will need to be connected , in one place to the ground buss in the Dist box. The D-box will thus need to be grounded. And MSW inverters, generally are not grounded unless specified by manufacturer.

What do you want to run with the inverter? this has a bearing on which type is best suited.

Thanks for your input so far....

I want to run 2 15 watt cf lights as needed...

And charge a few cordless tools as needed...

The reason I want it in a proper dist box is I plan to add a room or two in the future and I wanna run normal ac circuits from the dist box like a 'normal' house...

Reguardless..the MAX id ever draw at a time is 200w

I got the panels & batteries under control... I'm just looking for how to transition from inverter to the ac dist bos..and ground it properly...

..to make myself clear my main concern is saftey ...

So do I bond at the dist box or no??

Thanxxx again everyone

--cupp

westbranch · December 2013

Re: How do I connect inverter to AC breaker box?

If you get a TSW inverter, there will, probably, be a ground connection point in the inverter and a ground wire (#10 ga ?)would be run to the 110 Distribution box and from there to your ground rod with, normally, #6 bare copper.

You want all circuits to have circuit breakers, 15Amp. And between the CC and battery and Inverter

Are you alone in this house or are there other users? there are several stories about 'guests', 'family' that blow the circuitry on small inverters, due to ....DUH? I didn't know... (fill in excuse) ....

If so you might consider going a bit larger, the standby rate would be the same or very close regardless of size chosen, up to ~ 800 Watts.

1st axiom of solar seems to be "loads WILL grow over time"

mike95490 · December 2013

Re: How do I connect inverter to AC breaker box?

1) Be absolutely sure your inverter is of the type that can be hardwired (most true sinewave inverters can be)

2) The inverter will / should have grounding information in it's manual.

3) the distribution panel should have an internal bond or jumper between earth and neutral.

4) grounding the batteries and PV wires, USUALLY, the negative wire is bonded to the same earth ground as the distribution panel.

5) proper fuses on the battery and charge controllers and inverter

6) I'd like to suggest the Morningstar Suresine 300w inverter as a nice reliable one.

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

mike95490 wrote: »

1) Be absolutely sure your inverter is of the type that can be hardwired (most true sinewave inverters can be)

2) The inverter will / should have grounding information in it's manual.

3) the distribution panel should have an internal bond or jumper between earth and neutral.

4) grounding the batteries and PV wires, USUALLY, the negative wire is bonded to the same earth ground as the distribution panel.

5) proper fuses on the battery and charge controllers and inverter

6) I'd like to suggest the Morningstar Suresine 300w inverter as a nice reliable one.

Thanks...

Can you or anyone reccomend an.inverter like the suresine that can do 1000-1500 watts..

I like morningstar but on second thought I will use more than 300w...

So I'm.looking for an inverter that can be HARDWIRED to ac rated 1000-1500w

Thank you all

--cakez

westbranch · December 2013

Re: How do I connect inverter to AC breaker box?

There are Cotek and Samlex. NAWS sells Samlex. http://www.solar-electric.com/sasiwain1.html

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

westbranch wrote: »

There are Cotek and Samlex. NAWS sells Samlex. http://www.solar-electric.com/sasiwain1.html

Thank you so.much...it looks like this one should work

http://www.solar-electric.com/samlex-pure-sine-wave-inverter-pst-1500-12.html

I can't thank you all enough for helping me

Hardwire output 1500w..just what I need...

One last question.. do you or anyone here have experience with the samlex brand?

Are they as reliable as morningstar?

Thanxxx

--cuppy

Rybren · December 2013

Re: How do I connect inverter to AC breaker box?

I have the 24V version of the PST-1500. I only had it running from late summer to Thanksgiving, but it seemed to do the trick for me. The camp is closed up for the winter, so I'll have to wait until spring to really put it through the paces.

There is an internal N-G bond in the inverter, so if hardwiring to a panel, you'll either have to remove the internal bond or not do the bond in the panel. You don't want the bond in both places.

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

Rybren wrote: »

I have the 24V version of the PST-1500. I only had it running from late summer to Thanksgiving, but it seemed to do the trick for me. The camp is closed up for the winter, so I'll have to wait until spring to really put it through the paces.

There is an internal N-G bond in the inverter, so if hardwiring to a panel, you'll either have to remove the internal bond or not do the bond in the panel. You don't want the bond in both places.

Understood.
Thank you sir.

The inverter is bonded internally so DON'T bond ground and neutral at the ac service box/panel...

Can you or anyone explain that logic to me?

Thank you

Greetings from the desert

--kakez

vtmaps · December 2013

Re: How do I connect inverter to AC breaker box?

cupcake wrote: »

The inverter is bonded internally so DON'T bond ground and neutral at the ac service box/panel...

Can you or anyone explain that logic to me?

Your system must have a bond between neutral and ground. But it MUST have ONLY ONE bond. If it's bonded in your inverter AND in your service panel, you will have trouble.

The real fun comes when you have multiple power sources... for example, do you have a generator? If so, does it have a neutral-ground bond? If you do have a generator, do you have some sort of transfer switch (between inverter and generator)? If so, you may need to pay attention to how the transfer switch deals with neutral, ground, and bonding.

--vtMaps

mike95490 · December 2013

Re: How do I connect inverter to AC breaker box?

vtmaps wrote: »

Your system must have a bond between neutral and ground. But it MUST have ONLY ONE bond. .....

Is this because of Code Requirements, or Lightning ground surges ??

BB. · December 2013

Re: How do I connect inverter to AC breaker box?

mike95490 wrote: »

Is this because of Code Requirements, or Lightning ground surges ??

It is avoiding having "operating current" in the ground line and having parallel "redundant" current paths.

The redundant part is if the "neutral fails", the load will shut down. If there is a parallel green wire path, then the current will simply shift over to the green wire and you would now have no "backup" safety ground.

Another reason is parallel paths become difficult to control/predict where the current will actually flow. You could have the return current for the electric drier flow through a 15 amp 14 AWG ground wire and toast the ground wire.

And for AC+DC Backup power systems, the parallel current paths are "even worse". A 12 volt battery bank will have 10x the current vs its 120 VAC counter part. If your parallel grounding connection on the AC side can include DC currents--The AC White and Green wires may carry way more than their rated current because of the parallel DC current path (this is very much a possibility when the DC Bonding is both in the AC inverter and the AC main panel).

It is just easier (and safer) to have "single point" green wire / white wire / DC return+Battery Bus bonding in one spot.

-Bill

cupcake · December 2013

Re: How do I connect inverter to AC breaker box?

BB. wrote: »

It is avoiding having "operating current" in the ground line and having parallel "redundant" current paths.

The redundant part is if the "neutral fails", the load will shut down. If there is a parallel green wire path, then the current will simply shift over to the green wire and you would now have no "backup" safety ground.

Another reason is parallel paths become difficult to control/predict where the current will actually flow. You could have the return current for the electric drier flow through a 15 amp 14 AWG ground wire and toast the ground wire.

And for AC+DC Backup power systems, the parallel current paths are "even worse". A 12 volt battery bank will have 10x the current vs its 120 VAC counter part. If your parallel grounding connection on the AC side can include DC currents--The AC White and Green wires may carry way more than their rated current because of the parallel DC current path (this is very much a possibility when the DC Bonding is both in the AC inverter and the AC main panel).

It is just easier (and safer) to have "single point" green wire / white wire / DC return+Battery Bus bonding in one spot.

-Bill

Thank you Bill and everyone who replied...

Gonna get the samlex inverter ...leave a box UN bonded...

Thank you.. merry xmas ....75 and sunny here in the desert...

How do I connect inverter to AC breaker box?

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