Generac 20KW home generator install

[CrashTestDummy]

Jeff,

That's a nice set up, and a nice 'build thread'. I've contemplated such a thing for our house. We have a couple of generators that we use when trouble strikes. With hurricanes, which is a problem here, you can expect between 1 and 2 weeks without power. We discovered that we can mostly live without house power. Cooking dinner on the gas grill is actually kind of fun, for a while. The big problem is not having power to our well. Having to get water is a REAL PITA. Because of that, I've hooked our well up so that it plugs into house power. When we have a power outage, I'll just go fire up one of the generators and plug the well into that.

It would be really nice, however, to be able to run the rest of the house while the neighborhood is dark. Thanks for sharing. $9K for a 20KW system is within reach for us.

Gene Beaird,
Pearland, Texas

 

[shamrock12]

I'm not sure I see how this interlocking device could prevent both utility supply and generator supply from being inadvertently turned on at the same time. This interlocking device appears to function by rotating rather than sliding back and forth. Those "legs" of the interlocking device should be placed between (inside) those two breaker handles, not outside, so that way only one handle could be in the ON position at a time.

 

[Stuart in MN]

I'm not sure I see how this interlocking device could prevent both utility supply and generator supply from being inadvertently turned on at the same time. This interlocking device appears to function by rotating rather than sliding back and forth. Those "legs" of the interlocking device should be placed between (inside) those two breaker handles, not outside, so that way only one handle could be in the ON position at a time.

If you look closely there's a bar in the middle between the handles of the two breakers - when one of the levers pushes on one breaker to close it, the bar in the middle opens the other one.

 

[mjeff87]

yup....pardon my horrible skilz with MS Paint, but there is a sliding bar between the two service breakers that synchronizes them:

Jeff

 

[mothgrey]

Hey neighbor I'm in Chesterfield Va and had one done and finished last month also. My neighbors son installed it he is an electrician and installs about 6 a week for the past year. All in all I got a good price and I had it installed across the driveway away from the house. Did a pad like yours but with 4x4. All inspected and ready to run. Also mine is propane no natural gas here.
I love that it test itself weekly.

 

[KYGTP]

Hey neighbor I'm in Chesterfield Va and had one done and finished last month also. My neighbors son installed it he is an electrician and installs about 6 a week for the past year. All in all I got a good price and I had it installed across the driveway away from the house. Did a pad like yours but with 4x4. All inspected and ready to run. Also mine is propane no natural gas here.
I love that it test itself weekly.

So how far of a run was the wire from your Gen. to your house. I would like install a Gen next to my detached garage that I had built in 2010, and I ran conduit from the garage to my house to run the wires for a Gen. My Run is about 100 ft or so.

I too will have a 500 gal. propane tank that I will be running off of that is for my garage only, so I will not drain the house tank if the power goes out.

 

[Speedy Petey]

So how far of a run was the wire from your Gen. to your house. I would like install a Gen next to my detached garage that I had built in 2010, and I ran conduit from the garage to my house to run the wires for a Gen. My Run is about 100 ft or so.

I too will have a 500 gal. propane tank that I will be running off of that is for my garage only, so I will not drain the house tank if the power goes out.

For a run that far you'll need TWO conduits.
One for the power conductors, and one for the control conductors.

 

[KYGTP]

For a run that far you'll need TWO conduits.
One for the power conductors, and one for the control conductors.

Well, I do have two conduits running to the house, but one has cat5 cable in it for my alarm system for the garage, so that I have a key pad in my house for the garage.

So would I be able to run the controls through the conduit with the cat5 cable, since the I am only using the cat 5 for a alarm key pad? How many wires do the controls use?

 

[Speedy Petey]

Well, I do have two conduits running to the house, but one has cat5 cable in it for my alarm system for the garage, so that I have a key pad in my house for the garage.

So would I be able to run the controls through the conduit with the cat5 cable, since the I am only using the cat 5 for a alarm key pad? How many wires do the controls use?

Definitely not.

Most Generacs use six "control" wires. Two of them carry 240v for the sensing circuit, so unless the Cat5 is rated for 300v, which it is not, you cannot use that conduit.

It'll work, but it won't be right and may cause problems down the road.

 

[KYGTP]

Definitely not.

Most Generacs use six "control" wires. Two of them carry 240v for the sensing circuit, so unless the Cat5 is rated for 300v, which it is not, you cannot use that conduit.

It'll work, but it won't be right and may cause problems down the road.

Thanks for the info. I guess I just need to get a Rep out here to see what I got and go from there.

 

[mike_s]

I know you said this is an "automatic panel", but this looks like a manual transfer switch?

or is that just so you can override the automatic part and transfer manually if needed?


btw... thanks for the detailed install thread.

 

[mjeff87]

it's automatic......what you can't see is behind that vertical strip of metal in the center is a small "cam" lobe attached to an electric motor. When the panel senses loss of utility the motor actuates and spins the cam anti-clockwise into the transfer arm for the generator breaker (which also opens the utility breaker). When utility restores, it spins again and changes their positions back to how you see them in the pic.

Jeff

 

[mike_s]

it's automatic......what you can't see is behind that vertical strip of metal in the center is a small "cam" lobe attached to an electric motor. When the panel senses loss of utility the motor actuates and spins the cam anti-clockwise into the transfer arm for the generator breaker (which also opens the utility breaker). When utility restores, it spins again and changes their positions back to how you see them in the pic.

Jeff

thanks. makes sense.


Is your whole house just 125 amps? or is that just the circuits that are on the transfer switch ? (with another main panel elsewhere?)

 

[mothgrey]

So how far of a run was the wire from your Gen. to your house. I would like install a Gen next to my detached garage that I had built in 2010, and I ran conduit from the garage to my house to run the wires for a Gen. My Run is about 100 ft or so.

I too will have a 500 gal. propane tank that I will be running off of that is for my garage only, so I will not drain the house tank if the power goes out.

Sorry just saw this. Mine was run about 35 feet from the house and the underground tank is about 25 feet from the generator. They used one 1.5" conduit

 

[saunD]

Here is a great article that should help you get a head start .. It help us a bunch when trying to figure out where to install our home standby generator.... hope it helps you as well...

http://www.norwall.com/blog/generator-information/locating-standby-home-generator-installation/

 

[brettwind102]

I think my neighbor said your supposed to run them 15mintues every week for maintance for the genetaor. One of the people down the road has a tank a little away from his house with maybe 250-500gallons seperate

 

[HoosierBuddy]

i checked with our natural gas supplier and asked them 'if they could supply NG during an outage like the northeast had in 2003. There answer was "no all our pumps and valves are electric and we do not have backup generators on them. I went with a 500 gallon propane tank only for that reason. Most of the generators are dual fuel but have to have somethings changed over to convert from one to the other. Don't get your hopes up that in a disaster that utility could supply you, because in 2003 they could not supply the northeast.

That's hilarious. Who told you that? The receptionist?

Pumps? Electric Valves? On a natural gas distribution system?

Phil

 

[Stuart in MN]

That's hilarious. Who told you that? The receptionist?

Pumps? Electric Valves? On a natural gas distribution system?

Phil

They do use booster pumps and control valves.

 

[Milton Shaw]

I talked to an engineer at the gas utility, he called another engineer at the regional supplier and they said the same thing. With hurricane Sandy one of the first things the utilities did was turn off natural gas because of all the leaks/damaged houses. Where would you be if they did that. Owned propane tank is the only sure supply.

 

[HoosierBuddy]

They do use booster pumps and control valves.

Uhh...no...

Natural gas is moved by compressors, not pumps. Those compressors are not part of the distribution system. They are part of the interstate transmission system. Many of those compressors are engine driven, and some are motor driven, but since the T-lines are hundreds of miles long, and have redundant compression at many places, the chances of them not being able to move gas from a power outage (even if it was regional) are nil-when you consider the reduction in load that results when the power goes off (most gas usage DOES require power to run).

And while there are installations of electrically operated valves on gas systems, they are rare (I personally have never seen one in the 20 years I've been working in the natural gas industry...just heard about them from others) the use is for safety valves that can be closed in an emergency due to line ruptures. It isn't to control pressure on distribution systems. That's done with regulators with pneumatic controls.

Have you ever heard of a gas outage caused because the power went off? After 20 years in the industry, I'm not aware of one. The biggest danger to you losing gas service is a guy in your neighborhood with a backhoe. An earthquake could knock a system flat too. But power outage? I sleep right through them. No concern to us.

Phil

 

[HoosierBuddy]

I talked to an engineer at the gas utility, he called another engineer at the regional supplier and they said the same thing. With hurricane Sandy one of the first things the utilities did was turn off natural gas because of all the leaks/damaged houses. Where would you be if they did that. Owned propane tank is the only sure supply.

Shutting off the gas for "safety concerns" is a real possibility.

That would be an issue Milton, I agree. It's not because of electric valves and pumps though. It's mainly because of an abundance of caution on the ground.

Phil

 

[bobscogin]

Shutting off the gas for "safety concerns" is a real possibility.

Around here (Southeast Louisiana) trees usually blow over with the root system intact, often taking out gas lines with it, so it's pretty common to see the gas supply terminated for safety. As result propane is the predominant fuel source used here for generators.

Bob

 

[jethrodawg]

I have the 8kW portable generator (12kW surge) that hooks into my panel so I can power any circuit I want. Obviously I can't run the dryer or electric stove but can poiwer everything else like boiler for heat.

I can't imagine going to that kind of expense for something used so sparingly. Even up here in New England (I'm originally Warrenton ) where we get major snow storms the need for a generator is tough to justify based on ROI.

Nice set-up, just don't ever plan to see that money back if you sell.....

 

[worahm]

Recently, two multi speed air handler blower motors failed during a 4 hour power outage when my neighbor was running his 20KW whole house generator.

My neighbor has two Carrier heat pumps with multi speed air handler blowers, that were running as AC during the power outage. It is unclear weather both AC's were running at the same time. The blower motor speed is controlled by the system controller dependent on temperature, demand and whether conditions.

The generator has been in service for 7 years so it is unlikely that it has appliance management circuitry. With 20KW, I am not certain it would have mattered.

Based on my limited knowledge of motors, I suspect that multi speed motors may be more susceptible to failure then single speed motors when powered by poorly regulated voltage.

I am reluctant to assume that failing two multi speed motors at the same time when the motors were powered by a generator was a coincidence.

Can anyone explain to me if there is a possibility that poorly regulated power or any other component from a generator can cause a multi speed motor to fail?

I am considering installing a whole house generator and would like have a better understanding of why two blower motors failed while they were running on a generator before I proceed.

Any and all comments are welcome. Bill

 

[Teken]

Recently, two multi speed air handler blower motors failed during a 4 hour power outage when my neighbor was running his 20KW whole house generator.

My neighbor has two Carrier heat pumps with multi speed air handler blowers, that were running as AC during the power outage. It is unclear weather both AC's were running at the same time. The blower motor speed is controlled by the system controller dependent on temperature, demand and whether conditions.

The generator has been in service for 7 years so it is unlikely that it has appliance management circuitry. With 20KW, I am not certain it would have mattered.

Based on my limited knowledge of motors, I suspect that multi speed motors may be more susceptible to failure then single speed motors when powered by poorly regulated voltage.

I am reluctant to assume that failing two multi speed motors at the same time when the motors were powered by a generator was a coincidence.

Can anyone explain to me if there is a possibility that poorly regulated power or any other component from a generator can cause a multi speed motor to fail?

I am considering installing a whole house generator and would like have a better understanding of why two blower motors failed while they were running on a generator before I proceed.

Any and all comments are welcome. Bill

If I was to take a stab at the possible cause. I would gather the unit was over loaded and possible lull in power was present. When voltage goes down, current goes up in most electronics.

Given a multi-speed motor have various electronics that lull, sag, brown out, condition may have burnt out the two motors.

Just a wide guess, no proof what so ever.

Teken . . .

 

[2ManyProjects]

I talked to an engineer at the gas utility, he called another engineer at the regional supplier and they said the same thing. With hurricane Sandy one of the first things the utilities did was turn off natural gas because of all the leaks/damaged houses. Where would you be if they did that. Owned propane tank is the only sure supply.

Shutting off the gas for "safety concerns" is a real possibility.

That would be an issue Milton, I agree. It's not because of electric valves and pumps though. It's mainly because of an abundance of caution on the ground.

I wouldn't call it an "abundance" of caution; it was an obviously necessary move. Less than five miles from my shore home, an entire neighborhood (some 60-odd homes) called "Camp Osborne" burned to the ground for this very reason, before they made that call.

Before:

During:

After:

 

[Teken]

Wow, do you think you could have posted a bigger picture??

Teken . . .

 

[CNGsaves]

Nice install OP . . . that 20Kw Generac will provide you many years of whole house backup power.

Having NG (natural gas) as your fuel source is undoubtedly the lowest cost fuel, and likely the most reliable for the generator's expected use (ie power outages due to ice, windstorm, electrical grid overload, etc).

If circumstances warrant, then you could also pursue LPG propane as an alternative fuel, if you make necessary changes to Generac genset (ie and have say 100 lb bottle of LPG on hand).

Curious if you had any choice on the orientation of the genset?? What I mean is could you instead turn it horizontal to the house so the natural gas buried line would have had a straight shot to the unit?? This would have eliminated that awkward connection out to the side??

For landscaping, also would suggest removing grass around those buried natural gas lines coming out of ground (also electrical) so you won't be weed eating right next to pipe. Instead some sort of gravel on top of landscape fabric, with a couple appropriate shrubs (ie minimal roots, permanent leaves, etc) to hide those pipes.

Overall, really impressed with the install.

 

[getpecked]

Do you know what size the wire is from the panel to the generator? Looks to be about as far as my run will be.

 

[wyliesdiesels]

Do you know what size the wire is from the panel to the generator? Looks to be about as far as my run will be.

No 2 installations are exactly the same. Service/main breaker size, cable length/voltage drop, etc. all play a factor in deciding the correct wire size. Best thing to do is post up the specific details of your install and we will guide u!!

 

[getpecked]

No 2 installations are exactly the same. Service/main breaker size, cable length/voltage drop, etc. all play a factor in deciding the correct wire size. Best thing to do is post up the specific details of your install and we will guide u!!

Great, thank you. Instead of hijacking this post, I will start a new thread.

Thanks,
Ed.