Help me find a good & affordable generator transfer switch

[edge]

I have an 8 circuit that I'd part with. Was installed for 2 months before I upgraded to a larger generator with 12 circuits.
I still think i have the diagrams

 

[JimS]

Square D makes a number of choices that should be fairly easy to get from electrical distributors and not too spendy. They introduced some main panel interlocks that interlock a main breaker to a nearby smaller breaker about 5 years ago. With the exception of the interlock part everthing is available at box stores, distributors, etc.
http://ecatalog.squared.com/techlib/docdet...900892680126e4f

They also have a clip on interlock for two smaller breakers for under $20. It took me some time to find this as it was just before the above was introduced. It works well for me as I only wanted to run a minumum of circuits from a 5 kw portable generator occaisionally. Part number is QO2DTI.

http://ecatalog.squared.com/techlib/docdet...9008926801a669f

http://ecatalog.squared.com/catalog/174/ht...01/17401011.pdf

I got mine from Grainger(www.grainger.com). Their catalog number is 2DH32.
As I remember mine came with some sort of retaining clip for the breaker although the directions don't seem to show that - perhaps they eliminated that part.

I put this is a readily available (i.e. low cost)QO subpanel (from HomeDepot), fed it with a 60A feed from the main panel and ran all my critical loads off it. Used 30A breaker for generator feed. Putting in a subpanel made wiring easier too but this was for new construction. Hard to beat for cost but it doesn't have meters and such - I didn't need or want those anyway. For the inlet I hardwired a cord to a box in the garage and put the appropriate plug on the other end of it. Put a hook on the wall to hold the cord. Cheaper than a box mounted inlet and I can't loose the cord. Everything passed inspection and is to code AFAIK.

Here are a couple links to other discussions of this topic:
http://forums.mikeholt.com/showthread.php?...refering+QOCGK2

http://www.diyprojects.info/bb/ftopic64684.html

YMMV...

 

[drozwood90]

"The best way though, is to just get a system...unless you are doing something really advanced (solar / inverter / AND generator). "

I've looked into transfer switches for my generator, and it appears some sort of UL approved multi-pole double-throw switch is the inexpensive solution to avoid frying the lineman. Your comment about solar has me wondering how linemen are protected from solar installations where the systems are designed and intended to send power from the consumer back to the power company. Do solar installations monitor the line and disconnect if they don't see voltage on the mains?

Depends on the system. The Xantrex I was looking at (XW), can have multiple things feeding into it.

Then you tell it the priority.

You hook your entire house into it, batteries, external generator, solar panels, battery charger (for the solar). Then, to meet the UL requirement of NO "ISLANDING" they just sense there is no power coming in from the grid and sever the connection. Since they are battery backed, you IMMEDIATELY draw the the batteries. The solar can then recharge the batteries, or a generator can power the unit.

When power is restored, the unit goes back to selling / using power from the grid (as per your programming).

MOST, I find, just shut down. So no grid, no power to your house (even though you've got 22K in panels on your roof!!).

--Dan

 

[drozwood90]

I've got 400 amp service in my new home - two 200 amp panels. I have a 30kW generator with an automatic transfer switch powering one of the panels that powers the essentials that need to run should power fail when I'm not home: refrigeration, HA, HVAC, some lighting, alarm, etc. The other panel powers non-essentials: cooking, water heating, balance of lighting, pool heater, etc. In order to power both panels from the genset, I have to throw a manual breaker to connect the two panels and on the second panel, flip the lock-bar double-throw breaker mentioned earlier. The electrician originally wired both panels as manuals until I mentioned I had spec'd an ATS. This is the solution we arrived at. If you want, I can take pics tonight and send or post them.

Kevin

I'd be interested in pictures / model numbers / and what kind of generator you are using.

What kind of HA are you using? Do you find that it WORKS on the generator power? Or do you just suspend MOST things until you are back on grid?

My guess is you are using Z-Wave? It seems MOST people that get reliable use, are using Z-Wave. I've only heard of one guy that is using UPB and a generator (I use UPB, which is where my interest is coming from!!)

--Dan

 

[electron]

This is even better, I just need to find a local dealer which has the SquareD Interlock system. I can't see a reason why not to do this.

Square D makes a number of choices that should be fairly easy to get from electrical distributors and not too spendy. They introduced some main panel interlocks that interlock a main breaker to a nearby smaller breaker about 5 years ago. With the exception of the interlock part everthing is available at box stores, distributors, etc.
http://ecatalog.squared.com/techlib/docdet...900892680126e4f

They also have a clip on interlock for two smaller breakers for under $20. It took me some time to find this as it was just before the above was introduced. It works well for me as I only wanted to run a minumum of circuits from a 5 kw portable generator occaisionally. Part number is QO2DTI.

http://ecatalog.squared.com/techlib/docdet...9008926801a669f

http://ecatalog.squared.com/catalog/174/ht...01/17401011.pdf

I got mine from Grainger(www.grainger.com). Their catalog number is 2DH32.
As I remember mine came with some sort of retaining clip for the breaker although the directions don't seem to show that - perhaps they eliminated that part.

I put this is a readily available (i.e. low cost)QO subpanel (from HomeDepot), fed it with a 60A feed from the main panel and ran all my critical loads off it. Used 30A breaker for generator feed. Putting in a subpanel made wiring easier too but this was for new construction. Hard to beat for cost but it doesn't have meters and such - I didn't need or want those anyway. For the inlet I hardwired a cord to a box in the garage and put the appropriate plug on the other end of it. Put a hook on the wall to hold the cord. Cheaper than a box mounted inlet and I can't loose the cord. Everything passed inspection and is to code AFAIK.

Here are a couple links to other discussions of this topic:
http://forums.mikeholt.com/showthread.php?...refering+QOCGK2

http://www.diyprojects.info/bb/ftopic64684.html

YMMV...

 

[Kevin L]

I've got 400 amp service in my new home - two 200 amp panels. I have a 30kW generator with an automatic transfer switch powering one of the panels that powers the essentials that need to run should power fail when I'm not home: refrigeration, HA, HVAC, some lighting, alarm, etc. The other panel powers non-essentials: cooking, water heating, balance of lighting, pool heater, etc. In order to power both panels from the genset, I have to throw a manual breaker to connect the two panels and on the second panel, flip the lock-bar double-throw breaker mentioned earlier. The electrician originally wired both panels as manuals until I mentioned I had spec'd an ATS. This is the solution we arrived at. If you want, I can take pics tonight and send or post them.

Kevin

I'd be interested in pictures / model numbers / and what kind of generator you are using.

What kind of HA are you using? Do you find that it WORKS on the generator power? Or do you just suspend MOST things until you are back on grid?

My guess is you are using Z-Wave? It seems MOST people that get reliable use, are using Z-Wave. I've only heard of one guy that is using UPB and a generator (I use UPB, which is where my interest is coming from!!)

--Dan

Hi, Dan.

Here's the info:

1. The generator is a 30kW water-cooled genset from Kohler, model 30RES. Here's a link.

2. Automatic Transfer Switch (ATS) is a 200-amp model from Kohler. Can be mounted inside or out. Here's a link.

3. Here are links to pictures of the panels. They are Square D:

All Panels - ATS on Bottom Right

Panel Fed by ATS

Manual tranfer switch

Manual interlock in other panel

4. I'm just starting to install the HA. I have an Elk M1G that I just activated. I ordered a HomeTroller Series 2 the other day that should be here soon. I run a Windows 2003 SBS network in the home and they all run fine on the generator. The UPSes don't mind the power from the generator. Kohler's power is pretty clean. I'm hoping not to suspend anything when running on the generator. Since it's only 30kW, I'll have to watch some of the high-amperage items like the induction cooktup and Advantium oven. Most other things should run fine with proper power management.

5. My lighting is hardwire: Centralite's LiteJet. I will be integrating JetStream into it in the near future to cover circuits not on the LiteJet.

HTH,

Kevin

 

[drozwood90]

I've got 400 amp service in my new home - two 200 amp panels. I have a 30kW generator with an automatic transfer switch powering one of the panels that powers the essentials that need to run should power fail when I'm not home: refrigeration, HA, HVAC, some lighting, alarm, etc. The other panel powers non-essentials: cooking, water heating, balance of lighting, pool heater, etc. In order to power both panels from the genset, I have to throw a manual breaker to connect the two panels and on the second panel, flip the lock-bar double-throw breaker mentioned earlier. The electrician originally wired both panels as manuals until I mentioned I had spec'd an ATS. This is the solution we arrived at. If you want, I can take pics tonight and send or post them.

Kevin

I'd be interested in pictures / model numbers / and what kind of generator you are using.

What kind of HA are you using? Do you find that it WORKS on the generator power? Or do you just suspend MOST things until you are back on grid?

My guess is you are using Z-Wave? It seems MOST people that get reliable use, are using Z-Wave. I've only heard of one guy that is using UPB and a generator (I use UPB, which is where my interest is coming from!!)

--Dan

Hi, Dan.

Here's the info:

1. The generator is a 30kW water-cooled genset from Kohler, model 30RES. Here's a link.

2. Automatic Transfer Switch (ATS) is a 200-amp model from Kohler. Can be mounted inside or out. Here's a link.

3. Here are links to pictures of the panels. They are Square D:

All Panels - ATS on Bottom Right

Panel Fed by ATS

Manual tranfer switch

Manual interlock in other panel

4. I'm just starting to install the HA. I have an Elk M1G that I just activated. I ordered a HomeTroller Series 2 the other day that should be here soon. I run a Windows 2003 SBS network in the home and they all run fine on the generator. The UPSes don't mind the power from the generator. Kohler's power is pretty clean. I'm hoping not to suspend anything when running on the generator. Since it's only 30kW, I'll have to watch some of the high-amperage items like the induction cooktup and Advantium oven. Most other things should run fine with proper power management.

5. My lighting is hardwire: Centralite's LiteJet. I will be integrating JetStream into it in the near future to cover circuits not on the LiteJet.

HTH,

Kevin

Kevin,

That was above and beyond!

Thank you so much for all the pictures and links!

As for the Automation switches, it helps...but doesn't. It helps to say that you don't KNOW if UPB will work or not...but it doesn't help me to say that you dn't have issues...well, you are <southerndrawl>HARDWARED!!</southerndrawl> If I get really into the Kolar, maybe I'll send you a few switches you can try for me!

I've been going back and forth on what kind of generator to get...I think I've settled on a cheapy little manual guy, so I can use it on my 30' trailer as well. Kind of a dual purpose! I'd love to have automatic switchover.

Oh well, again, thank you so much for all the information! It was VERY helpful! I just hope that the generator I get is high enough quality that my UPB switches are not damaged when running on it. I'm not worried about anything sensitive (server, TVs etc.) as they are all plugged into APC UPS's.

--Dan

 

[mustangcoupe]

I always thought manually switching even with a safety interlock was aginst code. Because there could still be "neutral voltages" and that is why a ATS is used. I believe this also disconnects your neutral form the utility service and connects it to the generator neutral only.

But I have been known to be wrong too.


edit: spelling

 

[Kevin L]

I always thought manually switching even with a safety interlock was aginst code. Because there could still be "neutral voltages" and that is why a ATS is used. I believe this also disconnects your neutral form the utility service and connects it to the generator neutral only.

But I have been known to be wrong too.


edit: spelling

I'm not sure about where you are, but it's definitely legal in Charlotte County, FL. My home was finished in 12/07, and the electrician originally wired it entirely manual. Passed inspection without problem. According to the electrician, most people go the manual route since the ATS is expensive ($1200+). I would have gone all ATS, but the county requires the generator be large enough to power everything in the home to be automatic. With responsible management, the 30kW is plenty for me. That's why I went with a mix of ATS and manual.

Kevin

 

[Kevin L]

Kevin,

That was above and beyond!

Thank you so much for all the pictures and links!

As for the Automation switches, it helps...but doesn't. It helps to say that you don't KNOW if UPB will work or not...but it doesn't help me to say that you dn't have issues...well, you are <southerndrawl>HARDWARED!!</southerndrawl> If I get really into the Kolar, maybe I'll send you a few switches you can try for me!

I've been going back and forth on what kind of generator to get...I think I've settled on a cheapy little manual guy, so I can use it on my 30' trailer as well. Kind of a dual purpose! I'd love to have automatic switchover.

Oh well, again, thank you so much for all the information! It was VERY helpful! I just hope that the generator I get is high enough quality that my UPB switches are not damaged when running on it. I'm not worried about anything sensitive (server, TVs etc.) as they are all plugged into APC UPS's.

--Dan

My pleasure, Dan. I get so much from this great community, I'm glad when I can give back.

If you just put in the interlock, you could always go to an ATS later on.

Have you called the UPB manufacturer to see what they say about generators and their switches?

Kevin

 

[Steve]

Have you called the UPB manufacturer to see what they say about generators and their switches?

I can tell you that UPB switches work fine on generator. At least they did for me for a few days during hurricane Wilma.

 

[bmil]

DavidL - Thanks for the info... Generac has a new line of air-cooled up to a 20kW model (with a load shedding autotransfer switch).
http://www.generac.com/Products/Residentia...ooled/20KW.aspx

Manual Transfer Interlock Switches - I know they are code and legal in NC too. My vacation home has one from SquareD. It's on my outside meter panel with a 50A plug-in for a portable gen to feed any circuit I haven't shut off the individual breakers to. Went this way initially for cost and will replace with an auto-transfer when I buy the whole house gen.

 

[gatchel]

Manual transfers legal here in PA, too. According to my electrician...

 

[drozwood90]

Have you called the UPB manufacturer to see what they say about generators and their switches?

I can tell you that UPB switches work fine on generator. At least they did for me for a few days during hurricane Wilma.

Steve,

Can you post details about your system / setup? What brand / model generator do you have? Are you running anything of size on your system...say and AC unit, or 220V Dryer...anything that might disturb the generator's output?

Thanks!

--Dan

 

[electron]

In case anyone is following the original topic, I have ordered the Square D interlock kit, $65 from my local Greybar.