You are not an electrician, but you did good! Looks good! The phrase 4 o is really 4 ought. Or 4/0. The conduits the connect from the new disconnect to the the sub panels should be 2 in. Good job again!
I know 4 ought is the correct term, I always assumed 4 0 was the slang term. That’s good to know about the conduit size. I thought that I pulled up a chart to tell me what size conduit I would need but maybe I just went with the smallest size that I would be able to make work. Thanks for the comment.
It’s #2 copper wire. It is rated for 115 amps if I remember correctly. The generator is a 20 KW generator which means it puts out 83 amps. That wire only needs to be sized large enough to handle the amps that the generator is putting out. Cummins put a 100 amp breaker on the generator so you have to size the wire to the capacity of the breaker on the generator. The 83 amps is more than enough power to get us through a power outage. My 400 amp service is unique, most houses have a 200 amp service. I increase the service to my house service because I thought I was going to pull power through my house to a shop in the future.
Using paralleled 4/0 gives you an ampacity of 360 A you cannot use the exception in the code book for 4/0 aluminum cable rating at 200 A. But when you go from your transfer switch to your panel you must now use 250 MCM aluminum or 3/0 copper cable to meet code. Your 400 amp breaker is now your service disconnect. Any sub panels off of that need to be rated at the rating of the overcurrent device that they are terminated. Your work looks very nice. Did the inspector question the conductor sizing?
Very nice install for a DIY!! Any problems with inspections or permits since you did it yourself? I know you used 4/0 aluminum and said you wished you used copper. I personally would love to use copper for all of it but price is almost prohibitive because of price. That aluminum is actually easier to bend that the smaller copper because Al is so much softer material. I also noticed that you had 2 wires per terminal on the meter. Did the utility co give you any problems about that? In my part of the country that double wire wouldn’t fly. Poco likes wire on individual terminal. Is there an exterior 400a disconnect? That’s another requirement so first responders can isolate power during an emergency. They still require it even though you have the service disconnect right on the other side of the wall. As another person said this was for sure an advanced diy install. Good looking job!
No problems with permits or inspection. Here you are allowed to wire your own house as long as you sign an affidavit saying that you will be living there for the next two years. I assume that is to keep people from building a house or flipping one and doing their own wiring and then selling it. No problems with the utility company. That was how it was wired from when the house was built and that was by a licensed electrician. No exterior disconnect. Maybe that would be required on a commercial structure but not on residential. Thanks for the kind words. I take my DIY stuff serious.
I ran a shielded wire in the same conduit as the feeder lines coming from the generator. If I remember correctly, the install directions said this was an option vs running a separate conduit just for the communication wire. It’s been working without issue. It has not caused me any problems.
Service entry aesthetics: (Jeremy Your meter panel is how it should be done) 1. I'm all for NEC code changes for safety, but why can it be done in an aesthetic and pleasing manner for the exterior of residential buildings? 2. Why aren't architects demanding the electrical manufacturers address exterior service disconnects 3. How about an external small mechanical disconnect that uses a spring cable to disconnect the breaker or knife switch on the inside of the building. Of course certified and listed. Residential 400 amp residential service looks like a small industrial building. Very large meter panel. Very large disconnects switch box, and a 200 amp panel box, and a second 200 amp panel box in the inside of the residence. Then down the road were coming up with smart panels even larger housings. How about adding to the engineering staff a design engineer and architect so their voices can be added to the design process and residential stop looking like small industrial plants.
Very good job. Can we run 2 separate 22kw generator with one 400A transfer switch?my main meterbase is 400A from hydro side same as yours and I have two 200A panel I just want to put each panel on one generator. Is it possible? Thanks
I don’t think so. The Transfer switch only has one input for the generator but two outputs so it can go to two separate 200amp panels. I think to do what you’re trying to do you would need two generators with its own transfer switch to each of the panels you’re trying to power. It would probably pencil out to be about the same cost as what you’re trying to do. This 400 amp transfer switch was double the cost of a 200 amp transfer switch. So if you’re already thinking about buying two generators which is by far the most expensive part of the project then purchasing two transfer switches for each of the panels would probably cost the same as trying to run it all through one giant transfer switch. However as I said in my video, I’m not an electrician, I just take my DIY serious.
Question --- I am confused a little -- Why did you bring in 4 Hots and 2 Neutrals from the Meter? Wouldn't ONE SET of wires be all that would be needed to attach to the top of the Transfer switch -- and then split the feed to the 2 - Load Centers at the lower end of the switch? Can you explain what there is a need for 4 hots and 2 neutrals feeding the ATS?
It’s a 400 amp service. A normal 200 amp service would only have two hots and one neutral. The four hot wires are 4/0 aluminum wire. 4/0 is only rated for 200 amps. To be able to get the 400 amps I needed to double up the wire. Another way of looking at it is each pair of 4/0 wires carry 200 amps at 240 volts. At the bottom of the ATS I split the amps by sending one set to the left panel and the other to the right panel. Each panel gets 200 amps.
The load wires to the panels are not rated for 400 amps so shouldn't this transfer switch feed in to a distribution panel first with 2-200 amp mains for proper overcurrent protection for load side conductors?
The transfer switch is the distribution center. The incoming 400 amps is split into two 200 amps before it goes out to the panels. That’s how I can run 4/0 aluminum to the panels.
This house was built 15 years ago and an outside disconnect was not required. I added this ATS and generator. The generator has a disconnect on it so anyone can disconnect the power coming from the generator if need be.
Very neatly done inside the Load Centers with the Grounds and neutrals -- shows your patience and perfectionism!
Very nicely done sir. Especially for a diy. Clean work.
Best explanation I've seen. Needing info for such setup - many 🙏👍
Thanks! I'm glad it was helpful.
Excellent tutorial and explanation. I'm doing the exact same set up, but also have parallel runs for the service. Very helpful!
Glad I could help.
You are not an electrician, but you did good! Looks good! The phrase 4 o is really 4 ought. Or 4/0. The conduits the connect from the new disconnect to the the sub panels should be 2 in. Good job again!
I know 4 ought is the correct term, I always assumed 4 0 was the slang term. That’s good to know about the conduit size. I thought that I pulled up a chart to tell me what size conduit I would need but maybe I just went with the smallest size that I would be able to make work. Thanks for the comment.
Impressive. Pretty advanced for a DIY.
Thanks!
What size wire do you have coming from the generator to transfer switch is it capable to handle the ampacity for the 400 amps ?
It’s #2 copper wire. It is rated for 115 amps if I remember correctly. The generator is a 20 KW generator which means it puts out 83 amps. That wire only needs to be sized large enough to handle the amps that the generator is putting out. Cummins put a 100 amp breaker on the generator so you have to size the wire to the capacity of the breaker on the generator. The 83 amps is more than enough power to get us through a power outage. My 400 amp service is unique, most houses have a 200 amp service. I increase the service to my house service because I thought I was going to pull power through my house to a shop in the future.
How were the DC connections? I haven't found a video explaining how those were done or what to keep in mind when making those terminations.
By DC are you talking about the battery that allows the generator to start in a power outage?
Using paralleled 4/0 gives you an ampacity of 360 A you cannot use the exception in the code book for 4/0 aluminum cable rating at 200 A. But when you go from your transfer switch to your panel you must now use 250 MCM aluminum or 3/0 copper cable to meet code. Your 400 amp breaker is now your service disconnect. Any sub panels off of that need to be rated at the rating of the overcurrent device that they are terminated. Your work looks very nice. Did the inspector question the conductor sizing?
The inspector and electric company looked at the work and was satisfied.
Good info, thanks
Very nice install for a DIY!! Any problems with inspections or permits since you did it yourself? I know you used 4/0 aluminum and said you wished you used copper. I personally would love to use copper for all of it but price is almost prohibitive because of price. That aluminum is actually easier to bend that the smaller copper because Al is so much softer material. I also noticed that you had 2 wires per terminal on the meter. Did the utility co give you any problems about that? In my part of the country that double wire wouldn’t fly. Poco likes wire on individual terminal. Is there an exterior 400a disconnect? That’s another requirement so first responders can isolate power during an emergency. They still require it even though you have the service disconnect right on the other side of the wall. As another person said this was for sure an advanced diy install. Good looking job!
No problems with permits or inspection. Here you are allowed to wire your own house as long as you sign an affidavit saying that you will be living there for the next two years. I assume that is to keep people from building a house or flipping one and doing their own wiring and then selling it. No problems with the utility company. That was how it was wired from when the house was built and that was by a licensed electrician. No exterior disconnect. Maybe that would be required on a commercial structure but not on residential. Thanks for the kind words. I take my DIY stuff serious.
How did you make your control wires going from the generator to ats I can’t figure that part out
I ran a shielded wire in the same conduit as the feeder lines coming from the generator. If I remember correctly, the install directions said this was an option vs running a separate conduit just for the communication wire. It’s been working without issue. It has not caused me any problems.
Service entry aesthetics: (Jeremy Your meter panel is how it should be done)
1. I'm all for NEC code changes for safety, but why can it be done in an aesthetic and
pleasing manner for the exterior of residential buildings?
2. Why aren't architects demanding the electrical manufacturers address exterior service disconnects
3. How about an external small mechanical disconnect that uses a spring cable to disconnect the breaker or
knife switch on the inside of the building. Of course certified and listed.
Residential 400 amp residential service looks like a small industrial building.
Very large meter panel. Very large disconnects switch box, and a 200 amp panel box, and a second 200 amp panel box in the inside of the residence.
Then down the road were coming up with smart panels even larger housings. How about adding to the engineering staff a design engineer and architect so their voices can be added to the design process and residential stop looking like small industrial plants.
Very good job. Can we run 2 separate 22kw generator with one 400A transfer switch?my main meterbase is 400A from hydro side same as yours and I have two 200A panel I just want to put each panel on one generator. Is it possible?
Thanks
I don’t think so. The Transfer switch only has one input for the generator but two outputs so it can go to two separate 200amp panels. I think to do what you’re trying to do you would need two generators with its own transfer switch to each of the panels you’re trying to power. It would probably pencil out to be about the same cost as what you’re trying to do. This 400 amp transfer switch was double the cost of a 200 amp transfer switch. So if you’re already thinking about buying two generators which is by far the most expensive part of the project then purchasing two transfer switches for each of the panels would probably cost the same as trying to run it all through one giant transfer switch. However as I said in my video, I’m not an electrician, I just take my DIY serious.
No you can't because the 2 generators would not synchronize to each other.
Thank you for information
You’re welcome
Question --- I am confused a little -- Why did you bring in 4 Hots and 2 Neutrals from the Meter? Wouldn't ONE SET of wires be all that would be needed to attach to the top of the Transfer switch -- and then split the feed to the 2 - Load Centers at the lower end of the switch? Can you explain what there is a need for 4 hots and 2 neutrals feeding the ATS?
It’s a 400 amp service. A normal 200 amp service would only have two hots and one neutral. The four hot wires are 4/0 aluminum wire. 4/0 is only rated for 200 amps. To be able to get the 400 amps I needed to double up the wire. Another way of looking at it is each pair of 4/0 wires carry 200 amps at 240 volts. At the bottom of the ATS I split the amps by sending one set to the left panel and the other to the right panel. Each panel gets 200 amps.
The load wires to the panels are not rated for 400 amps so shouldn't this transfer switch feed in to a distribution panel first with 2-200 amp mains for proper overcurrent protection for load side conductors?
The transfer switch is the distribution center. The incoming 400 amps is split into two 200 amps before it goes out to the panels. That’s how I can run 4/0 aluminum to the panels.
Is this the RA-400-SE transfer switch?
Yes I believe so.
Okay where does his emergency power or generator power come into the transfer switch ?
It’s the smaller red and black wires at the bottom of the switch.
What is the model of this transfer switch?
RA-400-SE
Jeremy, I take it your local jurisdiction did not require an outside disconnect.
This house was built 15 years ago and an outside disconnect was not required. I added this ATS and generator. The generator has a disconnect on it so anyone can disconnect the power coming from the generator if need be.