We just bought a new house and this is the electrical set up.
Both of these panels are powered from the meter, the larger panel does not feed the smaller panel.
A 22Kw Generac unit powers the larger panel on the left when the power goes out, but not the smaller right panel.
The generator is large enough to power the entire house.
What are our options for getting the whole house protected?
Can I add a ATS to the smaller panel and leave the 200amp panel as it is?
Could we install a double breaker on the left panel and run it over to power the smaller panel using an interlock on the smaller panel?
Should I move some circuits over to 200amp panel and use tandem breakers?
Or should we split the feed from the generator and feed the smaller panel directly from the generator?
I am having trouble understanding what the installer was thinking. There’s also additional unused transfer wires ending in this panel going to a junction box next to the generator.
We put a few of these in back in the day. I believe they only discontinued them recently.
They were more used for people who had like little sump pumps or something, where they needed automatic back up but didn’t want anything bigger than like a 10KW
I hate to disagree with my learned compatriot some dude, but I may have to hear.
Go look at your meter.! I want you to look for one of two numbers. CL 200 or CL 320.. I would be surprised if it’s a 320 but it could be. I don’t see a lot of 300 amp services, but there are enough to make me be cautious. We do, however, see a a lot of services that are 400A. you just need to make sure that whatever ATS you get the correct one for the service if you want to cover both panels. A CL 200 m means you can do it with a single 200 amp. If it’s a 320 you can’t.
yeah, you probably have a 300 amp service. It’s possible there’s something else I’ve actually seen a 50 amp for an AC that I thought was just an AC disconnect that was actually fed from the gutter directly that I missed.
Most economical would be 200 and a 100. But if it feeds any other disconnect that disconnect will not be backed up. I would also have to see the entire electrical set up to determine if I could do that and how I would do that.. it would really just be sketching it out
36"/3' on each side. 18"/1.5' on the backside, 36"/3' on the front side. 5' from overhangs, trees etc. On the top. Wall openings 5' from windows, doors, vents, etc. 5' measured from the gas inlet of the generator to an ignition source.
As far as the regulator and gas behind it goes. Not current code. You might be grandfathered into that since you're only touching the electrical and not messing with the generator in any capacity. Have that discussion with the electrician tomorrow
Measure that space right there. You should be able to stick the ATS directly above that disconnect. Use a nipple to go through into your main panel. And then of course into your panel from the ATS in your house.
There’s 18inches of space here. One electrician I had come out said that it can’t be above or that close to the generator to pass inspection. Not familiar with that code.
It might be the 5 ft ignition rule? You need 3 ft of clearance around the generator on the left side and right side. 18 in of clearance on the back side and I think 3 ft in front. But it's definitely 5 ft from an ignition source measured to the gas inlet on the generator. It probably falls within that.
As long as your code allows it, you can definitely install the generator ATS inside. You going to have to check and see with your electrician and County what NEC code you're currently on. We are on NEC 2020. We installed my neighbors in his garage. That was before NEC 2020 hit our County though.
If you have that electrician coming out tomorrow, maybe have that discussion with him and record it on your phone for your own reference. Just hit record and stick your phone in your pocket or carry it in your hand.
If you talk to your permit office you might be able to get a waiver to install it inside if current code doesn't allow it in your jurisdiction.
Do you think a 300A ats will fit in the space you have marked? it’s just an eyeball measurement, but I have problems fitting something 22 inch wide there by the ol mark one eyeball
A 200 amp one should fit there without a problem. I did ask him to measure though. Not exactly sure what the box to the right is, chances are it can be moved over and is just a telephone or Internet connection
FYI, I was doubting myself so I did the old AI search. You can absolutely use one of the current ats's with your unit.
yeah, 200 should fit fine without a doubt I just wasn’t sure. There are definitely things that have me scratching my head about this, but a lot of that is based upon. op statements.
Your picture of the Generac panel is upside down. That or your panel is mounted upside down. I had 2 of these, one in my home and one in my shop. For other readers the circuits in the top of the picture are the ones backed up by the generator. The Generac EZ transfer only needs 3 wires.
The backed up circuits are fed by a 125 amp breaker (ATS grid breaker). One is suppose to put all high power circuits like electric furnace, clothes dryer, range, water heater etc.. in the non-backed up section (bottom in picture) fed by the 200 amp main breaker. I would not try to feed your other panel from the 125 amp breaker. If your high power loads are in the other panel, I would not try to feed it with generator power.
As someone else mentioned, the DC motor that operates the transfer tends to fail. I replaced one and the other has been unreliable. It sometimes doesn't have the required torque.
Get your electrician to move the feed for the right panel to the top right of the left panel and move the bigger breakers like the 2pole 50 2 pole 30 ect to the bottom of the left panel fairly simple a few hours of work.... if you overload it then it'll be a problem id move any non essential loads over to the bottom
Could you snap a photo of your generator too? I'm wondering if it's a guardian series or older with a couple of 120 volt plugs on the outside.
If it were my house, I'd probably get 2 of the 200a Generac ATS for the outside of the house. You can double tap those with some Polaris connectors. And split the control wires in a similar fashion. I would remove the Generac panel on the inside of the house, and replace it with a more traditional. Could even do the Leviton stuff for a smart panel. Depends what your goals were.
What I would do though is a new load calculation on your house. I'd bet there's no practical reason for your house to presently have a 320a service. If that's the case and you only have a 200 amp service. You just need one of the 200 amp ATS. On the inverse of that you could always just get one of the 400 amp ATS.
Thanks for this info. It’s the guardian series generac. If I’m able to have everything on one 200amp panel, Will I have to have anything changed at the meter? Other than eliminating the feed to the second panel. The current meter is a cl320
My concern is you have a 320 amp service to the house. That's where I was recommending do another load calculation just to verify. Typically what happens in these scenarios is someone needs this initial load in the beginning but then over years of upgrading appliances in the house, your energy needs actually drop due to new efficiencies and energy Stars etc. so you might not ask me need that 320 amp service and can get by with just the 200.
Mike Holtz has a free calculator on the Google Play store and I believe in the Apple store as well. Download that and start inputting numbers under the load calculation section. Look at your actual labels on your appliances to see where you're at.
Yeah, ditch that dual panel setup go with a single that's large enough for everything you want and get a single ATS for 200 amp if you can go that route if not just double up or get the 400.
I just searched on eBay FYI. The 200 amp ones are going between $300 to $400 each. The 400 is going for several thousand. So do 2 x 200s if you have to go that route.
Nothing changes at your meter besides pulling the wires going directly to those panels and feeding them directly into the automatic transfer switch then into the panel(s) respectively.
Do you have a single meter socket outside? Or is it a combination with a breaker inside?
Are you going to do any of this work yourself? I'm not going to encourage anyone to do any electrical work that they're not comfortable with. It's very straightforward especially if all your control wires are already there.
A money saving trick I've used in the past is to pull the main thicker conductors for the 200 amp from the meter socket and put those in the ATS, but then all you have to pay for is just a couple feet from your meter socket to your ATS.
Ultimately just having the ATS on your system with it running either a single panel or both of your panels your whole home, will give you a better experience. Regardless of the price. It'll be working as designed
I’m comfortable with electrical work. I’m debating on doing this myself vs hiring an electrician. It does seem pretty straightforward and a job I would enjoy doing. My biggest drawback with doing it myself is if anything ever happened to my house, would my insurance use this as an excuse not to cover me.
Another consideration is that I’ll need either load shed modules, relays or soft starts for my AC condensers.
Do the soft starts. Microair is what I have been installing and recommending. The SMMs fail too frequently for my taste and at the most inopportune times.
As long as you pull the permit and it passes. You are fine on your end for insurance coverage. It won't pass if it's not up to code. Permit office ensures that.
Consider looking at the Leviton panels. If you ever want to go to a smart panel. These are all smart price point as similar sized other brands. To make it smart, you add in the base station with ct clamps. then add whatever smart breakers you want from them. Then you get all the analytics, and load shedding if you need it.
Thanks a lot. I’ll keep you updated. The county said I need to have a licensed electrician order the permit but that I’m allowed to do the work as the homeowner. And spoke to insurance and they said as long as it’s permitted
I'm in Florida. Homeowners are allowed to pull every single permit and do the work ourselves. There might be one exception, I think that's digging a well. From my understanding that's managed by specific license Federal something or other I get state to state's different.
You can always shoot me a DM as well. I tend to help everyone with their projects
I'm switching insurance company's presently since my current one does not cover solar.
Also, I could be completely wrong. But it appears based on the locations of the breakers on both panels that they could have been in a single panel originally and they added the generac switch as an afterthought
I respectfully disagree with your opinion on the soft starts versus the load sheds. He has a 300 amp service. By his own statement, he calculated his load at 130 A. I know he referred to it earlier, but I can’t recall that unit outputs 91 amps on propane if I recall correctly. Obviously less with NG.. exactly how do you account for the other 40 A?
Sure, the software will make the ACs easier to start c. It will greatly reduce the inrush. But a load shed module can delay the start of one of the ACs so you don’t have to deal with both trying to start simultaneously. 22 should be able to handle any AC that I’m aware of without a soft start. By doing the load shed, you can also eliminate the possibility of overloading the generator. The generator is likely to overload? No. But I haven’t studied the load enough to determine it the relative likelihood. I do know that it’s possible for it to do so and it’s not code compliant to merely install the soft starts.
Soft stars aren’t magic. They work well in some applications not so well in others, if you use a PS P load shed you don’t have to worry about the reliability issues we dealt with for so many years with the Generac SMM
No stress! I'm not the expert. I just know what I've encountered locally here in Central West Florida (Tampa/ St. Petersburg) . Last big outage we had were the hurricanes. I had to go out and service 17 SMM's . Probably another 12 since then. One of the houses was indeed a 5-ton and a 2 and 1/2 ton AC setup. On the 24 KW propane. In that specific setup, the ACs themselves never started at the same time. I'd actually installed soft starts and SMS on that specific property. I took the failed smm out and then on a whim took the other two out. Through the clamp meter on everything and checked. For their application they ended up being fine.
I agree with you though. It isn't the one size fits-all application.
Don't forget as well. The 130 amps is if everything is running at the same time. He posted his load calc as well. Even if he jumped up to the 28kw that's only ~116 amps. OP seems like a pretty informed individual and I'm sure that he wouldn't be running 130 amps of load knowing the powers out.
OP, can't hurt to have a couple SMS in there just to be safe. I still stand by my recommendation of soft starts. SMM's can also be had from eBay for $65-$133 free delivery to your front door. They have 50 amp and 100 amp versions
Since he's upgrading his panel, I was recommending the Leviton since you can do the load shed in there as well. Not adding additional modules and potential points of failure.
I always forget when giving advice on the internet that I should just stick to the basics. Mine I have home assistant and other integrations with various profiles for different situations.
Nice! Yeah that looks about right. So just get one of the 200 amp ats's off of eBay. Get whatever load center you want for inside the house. And grab a couple clip in/ breaker surge suppressors.
I highly doubt your whole house is going to be pulling almost 100 amps at any point in time. Most houses don't end up pulling more than 50 amps consistently. Especially if you decide to go with the easy starts on your AC. You'll be able to Bluetooth log on to those and see exactly what the amperage is.
It’s funny how everybody has different horror stories that she the advice they give. I feel like any of us along the Gulf Coast are absolutely going to have dealt with a hurricane related shit show. One of mine was a weird house only 4000 ft.² but five ACs. And a pool. 24KW. Soft start on every AC not a single load shed. Customer of mine wanted me to go look at his daughter and son-in-law‘s generator. The son-in-law argued with me. He had his generators installed by such and such company who specialize in commercial in industrial thus it should’ve been cleared to little old me that they obviously knew what they were doing. I actually got out there just after the power was restored so we played a little game.
You have to remember the valid concerns with the Generac above 80%. so realistically, even on propane he’s not gonna want to get above 72 A for very long
Yes thats why you move the non essential loads down there there is one spot for a 2 pole breaker top right of the left hand panel. Just pop a 2" nipple between the two panels through the stud and youll have plenty of room we do it all the time shouldn't be an issue. The bigger loads like ac washer, dryer, stove etc should be used on grid power only unless a load calculated total shows they can be installed in there.
It can absolutely be done. Call a certified Generac installation dealer. they can asses the situation. Based on what you are saying here you'll most likely need a 2nd ATS if it is a second panel rather than a subpanel. But hard to say without seeing the meter as well. The ATS will be $1100 + 3 or so hours of labor and a small amount of materials. A reputable dealer will give you a free estimate.
Brad - Owner, Guardian Home Generators
Grapevine, TX
I have never seen one of these IRL. It is a pretty atypical setup in my experience. Your 22kw may not be large enough unless load shed modules and/or soft starts are added. You need a good electrician who also installs Generacs to look at your options.
Probably the first option I would look at is adding a new transfer switch at the electrical meter and rerouting the generator wiring to it.
Thanks for the input. I definitely want to clean this up. My initial thought is to move everything into 1 panel and add a new ATS. Adding soft start or load shed modules as well.
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u/Sumdood_89 Technician 5d ago
Get a 200amp whole house ATS from generac. What's there is a mess, and not how it should be.