Generator Interlock kit questions

[dogwood]

I recently purchased a 7000 watt Honda EU7000is inverter generator in order to be able to safely run my 240v wood boiler, well, and/or some 120v stuff like circulator pumps during an outage. It was the smallest inverter generator I could find with 240v output (and painfully expensive I might add).

I happened to read the recent Whole House Generator thread here where BotherBart and others mentioned connecting their generators to their service panel with either interlock kits or transfer switch boxes. I'd never heard of an interlock kit before. It sounds like something I'd like to install if I could get some more information on what they are and what their installation involves.

Do interlock kits and transfer switch boxes differ, or are they the same thing? Do you plug the inverter generator's 240v outlet into the interlock or hard wire it in somehow? And are interlock kits/switches readily available at big box stores, or do I need to get one at an electrical supply outlet or online.

Any info you could provide on their make-up and installation would be appreciated. I had planned to use a bunch of extension cords and to rewire hard wired boxes into plug outlets to get things working, but the interlock or transfer box arrangement sounds so much better. Thanks.

Mike

 

[BrotherBart]

I don't have one but my neighbor does.

http://www.interlockkit.com/

 

[dogwood]

Thanks. Brother Bart.

 

[Wooden Head]

I recently purchased a 7000 watt Honda EU7000is inverter generator in order to be able to safely run my 240v wood boiler, well, and/or some 120v stuff like circulator pumps during an outage. It was the smallest inverter generator I could find with 240v output (and painfully expensive I might add).

I happened to read the recent Whole House Generator thread here where BotherBart and others mentioned connecting their generators to their service panel with either interlock kits or transfer switch boxes. I'd never heard of an interlock kit before. It sounds like something I'd like to install if I could get some more information on what they are and what their installation involves.

Do interlock kits and transfer switch boxes differ, or are they the same thing? Do you plug the inverter generator's 240v outlet into the interlock or hard wire it in somehow? And are interlock kits/switches readily available at big box stores, or do I need to get one at an electrical supply outlet or online.

Any info you could provide on their make-up and installation would be appreciated. I had planned to use a bunch of extension cords and to rewire hard wired boxes into plug outlets to get things working, but the interlock or transfer box arrangement sounds so much better. Thanks.

Mike

I've various transfer switch boxes. More of them then I could explain. The one I have will only handle 6 circuits. I found this to not work for my needs.

The interlock kit I found is very simple and effective.

 

[Dougsey]

Interlock kit is definitely the way to go. I was able to get one for my Square D Homeline panel at HD but it depends on your panel brand.

 

[claydogg84]

I have an interlock kit in my panel. It safely allows you to power your entire panel while the main breaker is shut off. This prevents back feeding the grid.

 

[dogwood]

Dougsey and claydogg84, were you able to install to install the kit yourselves? I'll check and see what Home Depot has once they plow the roads of the snow that fell last night. I've a Crouse-Hinds panel myself which I think is common enough they may stock a kit for it. You mentioned your interlock kits power the whole panel. Is it safe to assume then the interlock kits can service 240v input as well as 120v? Do either of you use the "noisemaker" I saw on the Interlock website that alerts you when power is restored? Appreciate your input and replies.

Mike

 

[Dougsey]

Hey dogwood,
If you are at all handy and comfortable inside your panel, the interlock is not hard to hookup. You have to input your genny to a double breaker located at the top of your panel, so you will probably have to move breakers around to accommodate that. Look at the link Bart posted as there's a picture there.

The interlock is really just a metal plate that prevents you from having your main and gen input breaker on at the same time.

You will also have to manage your loads because you are powering your whole panel while on generator. So you might want to throw the breakers for your electric dryer, range, a/c, etc. so they are not used by mistake.

I installed the PowerBack to let me know when street power is back on:

http://www.amazon.com/Reliance-Controls-THP108-PowerBack-Monitoring/dp/B003KREORA

 

[claydogg84]

They are fairly easy to install and I did it myself. I use the neighbors as my indication as to when power is restored. My generator doesn't get ran all that much so I don't mind letting it run an extra hour or so.

 

[velvetfoot]

I think I would look first to see if the mfr of the panel makes an interlock kit. SquareD made one for mine and I used it. You have to have two blank slots up top and right for the 240v. interlock breaker.

 

[dogwood]

Thanks for the quick replies. I'll check the Crouse-Hinds site, velvetfoot. I was thinking from the site BrotherBart provided the link to, that "Interlock" might be a proprietary name. If Square D made yours I take it isn't. Dougsey and claydogg84, I put all the breakers in myself originally, so I think Ill give it a shot. How does that metal plate attach to the front of the panel? I couldn't make it out from the picture on the Interlock site. Again thanks for your input.

Mike

 

[claydogg84]

Thanks for the quick replies. I'll check the Crouse-Hinds site, velvetfoot. I was thinking from the site BrotherBart provided the link to, that "Interlock" might be a proprietary name. If Square D made yours I take it isn't. Dougsey and claydogg84, I put all the breakers in myself originally, so I think Ill give it a shot. How does that metal plate attach to the front of the panel? I couldn't make it out from the picture on the Interlock site. Again thanks for your input.

Mike

You have to drill 2 holes to mount the lock out mechanism. Not all panels will have an available Interlock kit - mine is made by GE.

 

[velvetfoot]

I just took a picture of my SquareD interlock. Looks like 3 screws.

 

[dogwood]

Thanks again claydogg84. I very much appreciate you going to the trouble of posting that picture velvetfoot. It makes the switch installation crystal clear. And I think I found an interlock switch online that would fit my would fit my Crouse-Hinds box. How are your generators connected to the box for them on the outside of your home which connects to the service panel?

Mike

 

[claydogg84]

While remodeling my down stairs I had an exterior 30A outlet installed. You want to use a male outlet so you don't create a "suicide cord". Here's a picture of my interlock.

 

[velvetfoot]

Actually, I think it's called an 'inlet'.

 

[dogwood]

Thanks again claydogg84. Good pic and I liked seeing the label indicating it was an NEC approved device. I was wondering if the interlocks were to code. Appreciate your advice on the outside male outlet (or inlet as the case may be). I'd never seen one before "googling' it after reading your suggestion to use one. I also googled "suicide cord" as I never heard that expression before either. I'm getting an education here.

Mike

 

[claydogg84]

A suicide cord is what many people make so a generator can be simply plugged into a standard outlet and backfeed the house. It's extremely dangerous and can kill you, hence the name. If you do things the right way, this shouldn't be an issue.

 

[claydogg84]

And here's a link to the inlet box I have mounted outside on the deck.

(broken link removed)

 

[velvetfoot]

For example:
http://www.homedepot.com/p/Reliance-Controls-30-Amp-Power-Inlet-Box-PB30/202213702

 

[velvetfoot]

Great minds...

 

[claydogg84]

Great minds...

Go Mets!

 

[velvetfoot]

I'm liking our prospects for the season. I'm very tempted to go down for spring training.

 

[claydogg84]

I'm liking our prospects for the season. I'm very tempted to go down for spring training.

Now we're drifting off topic, but it should be another great season. I'm so thankful for the Nationals getting involved with Cespedes. Without them, we would have never landed him.

 

[Village Idiot]

I too have an interlock kit that was made by my panel manufacturer so I can run my whole house off of my big generator. It was as simple install.

Frequently, there are times, like at night, when I just want to run the blower on my fireplace and do not need to big generator running for that. So, I installed a transfer switch for just my blower using an EZ Generator Switch. I hook my little Harbor Freight generator and it bowers the blower while we are sleeping. It runs 5+ hours on a gallon of gas.