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labman
Aug 27, 2007, 11:04 AM
Two recent extended power outages reminded me I still don't have a connection for my generator. Yeah, I managed the fridge, freezer, coffee maker, etc on some extension cords, but the pump would be nice too, and maybe next time the furnace too. So I got a 6250 watt generator for $371. I would hate to spend more than that to connect it to the house wiring legally.

Anything new or I missed? Suicide cords are out.

These are popular, in stock at Lowe's, but $250 plus a bunch of wiring for a handful of circuits?
Gentran Corporation: Generator Transfer switches for home & business (http://www.gen-tran.com/eshop/10Browse.asp?Category=MTS6-10)

While I dithered, these seem to have gone up to $70. Biggest problem is they won't fit my box as is. Once I cut the notches in the plate to make it fit, it would no longer be the device that UL approved.
http://ecatalog.squared.com/pubs/Electrical%20Distribution/Load%20Centers/Accessories,%20QO%20(LK,%20PK,%20QO,%20QON)/1100HO0701.pdf

Even at $150 bucks, I am not sure any of their models would fit. Last year they did offer to make one that would for $250
Generator InterLock Kit - Introduction (http://www.interlockkit.com/intro2.htm)

Well past the point I should instal and $130.
Amazon.com: Reliance Controls 60-100 Amp Utility Switch for up to 15,000-Watt Generators #TCA1006D: Home Improvement (http://www.amazon.com/Reliance-Controls-000-Watt-Generators-TCA1006D/dp/B000HRWGPS/ref=sr_1_4/105-3908315-1706043?ie=UTF8&s=hi&qid=1188233360&sr=1-4)

Whoa, quite slick, but $700?
GenerLink.com - About GenerLink - The easy way to connect a home generator (http://www.generlink.com/about_generlink.cfm)

Anybody have any good ideas?

Is it OK to temporarily run a flexible cord through a hole in the wall if the hole is big enough for the end to go through?

tkrussell
Aug 27, 2007, 02:41 PM
What do you mean by not UL approved?

The Gentran or that style is a simple method to connect, and offers a mandatory isolation switching, simple to operate during an outage.

If a Gentran can't fit as close as the flexible conduit that is furnished with it, you can extend the flex with additional flexible conduit and a large junction box.

With the interlock, it is probably the easiest method, still need to do the input wring from the genset, need to be careful with load in the home as the entire panel is now live. This definitely, with good supervision, provides the most flexibility with everything having power, just watch not to overload the genset.

I don't see 60/100 amp breaker much use in your case.

The only other method is a large double pole double throw manual switch. In 100 amp frame talking easy $500.00, plus 100 amp wiring.

Would be better if the cord could pass through a sleeve, how about a PVC plumbing fitting with the 4" cleanout plug. See speedball for the details, beats the hell out of me. This way here you can open the cleanout and pass the cord and plug through when needed. Cord really should not pass through structure.

I really don't know any other methods to do this. I think the interlock is the best for you. I have confidence in your supervision during an outage.

KISS
Aug 27, 2007, 03:30 PM
Two recent extended power outages reminded me I still don't have a connection for my generator. Yeah, I managed the fridge, freezer, coffee maker, etc on some extension cords, but the pump would be nice too, and maybe next time the furnace too. So I got a 6250 watt generator for $371. I would hate to spend more than that to connect it to the house wiring legally.

Anything new or I missed? Suicide cords are out.

These are popular, in stock at Lowes, but $250 plus a bunch of wiring for a handful of circuits?
Gentran Corporation: Generator Transfer switches for home & business (http://www.gen-tran.com/eshop/10Browse.asp?Category=MTS6-10)

While I dithered, these seem to have gone up to $70. Biggest problem is they won't fit my box as is. Once I cut the notches in the plate to make it fit, it would no longer be the device that UL approved.
http://ecatalog.squared.com/pubs/Electrical%20Distribution/Load%20Centers/Accessories,%20QO%20(LK,%20PK,%20QO,%20QON)/1100HO0701.pdf

Even at $150 bucks, I am not sure any of their models would fit. Last year they did offer to make one that would for $250
Generator InterLock Kit - Introduction (http://www.interlockkit.com/intro2.htm)

Well past the point I should instal and $130.
Amazon.com: Reliance Controls 60-100 Amp Utility Switch for up to 15,000-Watt Generators #TCA1006D: Home Improvement (http://www.amazon.com/Reliance-Controls-000-Watt-Generators-TCA1006D/dp/B000HRWGPS/ref=sr_1_4/105-3908315-1706043?ie=UTF8&s=hi&qid=1188233360&sr=1-4)

Whoa, quite slick, but $700?
GenerLink.com - About GenerLink - The easy way to connect a home generator (http://www.generlink.com/about_generlink.cfm)

Anybody have any good ideas?

Is it OK to temporarily run a flexible cord through a hole in the wall if the hole is big enough for the end to go through?
I think you will find this page useful:

http://www.gvea.com/memserv/GVEA_generator_booklet.pdf

labman
Aug 27, 2007, 08:45 PM
I don't have any problem with cutting a couple of notches in the Square D plate and screwing it to my old GE box. But once I do that, it no longer will be exactly what UL approved, will it?

The Reliance is a double throw 60-100 amp switch. It would work, but no way am I going to disconnect my 100 amp feed and move it to the 100 amp side of the switch myself.

If I am going to pay somebody to mess with that, likely what I should do is scrap the old GE box and put a Homeline box in that the plate would fit. One approved for all the breakers I am using and with enough spaces for all the neutrals and grounds each on their separate bar.

If I do that, maybe I should go with arc fault breakers. Trouble is, my bedrooms are wired up with #14 and all the breakers I see are 20 amp.

On the cord, I was thinking of some sort of a 4'' pipe through the wall and a cap. Just take the cap off and pull the cord out and plug it in.

labman
Aug 29, 2007, 12:03 PM
Well, I have ordered an interlock kit, Generator InterLock Kit - Introduction (http://www.interlockkit.com/intro2.htm) They have agreed to modify their K-8010 to fit my old 2 handle box and still charge $150. I can fix the Coney Island problem with the old box by opening up a new main lug beach. Since the top of the existing box is 67'' high, and the bottom is only 10'' above the dryer, likely the sub panel will have to go to the left. I plan to use a fairly small supply breaker and move the lighter loaded 15 amp circuits to the new box and leave the watt hogs in the old. I need to free up 6 spaces plus get the circuit count down to the 20 on the box label. I will have to add a back feed breaker, a feed to the sub, and I want to add a surge protector. If I used an arc fault breaker to feed the sub and put all the bedrooms in it, would that meet the arc fault requirements for bed rooms? What would be the best way to run all the wires from one box to the other? Run a large conduit nipple through the stud from box to box? Several smaller ones? How many #14's in a 1'' pipe?

Since the UL approved 1970 main panel had one terminal strip for both ground and neutral, should I be better off leaving it that way rather than modifying it by adding an insulated neutral?

Who has the best prices on things like breakers and boxes, Lowe's or electrical supplies? Can I really save much messing with Ebay?

KISS
Aug 29, 2007, 12:55 PM
labman:

You need the isolated neutral in the sub-panel. In the main panel the ground and neutral are the same.

But, in highly sensitive environments, there is a neutral bus, a protective ground bus and a ground reference bus. Isolated ground receptacles (the orange ones) would have their grounds pulled to the ground reference bus. Grounds to motors and appliances would go to the protective ground bus and they would all be connected together at the main panel. I believe green with yellow stripe would be reserved for the clean ground, green for ground and white for neutral.

Nowadays they appear to be requiring the telco and cable connections to demark very close to the main panel so that the grounds will be at the same potential.

tkrussell
Aug 29, 2007, 03:00 PM
OK cool, now I know what you mean on the UL listing, and you are correct, modifying it at home would violate the listing. I am glad to hear the vendor will do it, and keep the cost the same.

On the subfeed breaker, won't you need a two pole breaker? I don't think there is one made, if so, then yes all the bedrooms would be AF protected. What brand is your main panel?

If you can use a straight nip large enough for the wires from the main panel to the new sub, then fine. You may want to use flexible conduit, makes bends etc, easy.

35 #14 will fit in 1" EMT,33 in 1" FMC (flexible metal conduit), and 36 in 1" GRC (galvanized rigid conduit). As long as the nipple is 24" or less, derating will not be necessary.

As long as the main panel has the main breaker in it, the neutral and ground need to remain bonded together.

Believe it or not,Lowe's may sell some parts as cheap if not cheaper than a distributor. They buy stuff by the train loads, and local distributors can have a hard time trying to be competitive. All I can say is price out the bill of material at both and buy the cheapest at each.

Did I miss anything?

labman
Aug 29, 2007, 04:51 PM
My panel is a GE TM210F. I was thinking of maybe only a 40 amp feed breaker since I think I have one on hand. That sounds small for a bunch of 15 amp circuits, but it is 40% of the main, and I will leave the range, A/C, kitchen, garage, laundry, etc. in the main. I am planning on using adjacent wall cavities, a 2'' long 1'' galvanized nipple should leave room for nuts and bushings. I hope many of the wires will reach their new breaker without a splice.

If GE makes a 60 amp double pole arc fault breaker, I won't find it at Lowe's. Just did a net search on it, and didn't find much. I did find my local supply house was cheaper on Cat 5 cable than Lowe's.

This means leaving the main and its feed from the meter alone. A huge factor on whether I can do the work with your support.

tkrussell
Aug 29, 2007, 05:41 PM
At the ready, sir.Can't wait to help. I love watching people work, that's how I make my living nowadays.

I like the 60 amp plan, gives some room. 40 maybe too tight, esp with pump motor, reefer, etc.


I have made splices 30 yr ago still working fine, the trick is twist the wires and use a good quality wirenut, I love 3M Scotchloks. Maybe that's why I love scotch (aka mother's milk)

I see at GE they only make 1 & 2 pole 20 amp breakers:

http://www.geindustrial.com/publibrary/checkout/Brochures|DEA-234A|PDF

labman
Aug 30, 2007, 04:22 AM
One upside to the whole project is that the better prepared I am for an extended outage, the less likely I will ever have one.

I have seen your suggestions of wire nuts before. I like them too. I have located what I hope is the neutral to frame link on my generator. I am thinking of cutting it, stripping the ends, and wire nutting it back together, easily undone before connecting into the house wiring, and redone otherwise. I could do a switch too.

labman
Aug 31, 2007, 08:34 PM
Thinking about this some more. I still have the problem of the dryer being under the breaker panel. Now if that met code in 1970 when the house was built, as long as I leave that panel there, it should be OK. I assume if I had decided to pay somebody to put a new one in, that the new one would have to meet current codes, 3' of open space? Now if I put the sub panel in the next wall cavity to the main box, where it would be the easiest, it will still be partly over the dryer. No good place to move the dryer. Any limits on how close to the door I can put the subpanel? The next wall cavity over isn't even a full one because of the door. I guess I could surface mount it.

Digging around today, the 40 amp breaker I remembered having, didn't turn up. If I have to buy one, may as well buy a bigger one.

Just how important are the arc fault breakers for bed rooms? Do you think eventually retrofitting will be required?

tkrussell
Sep 1, 2007, 04:16 AM
Electrical panels have always needed 30 inch wide clear access with no obstacles. I figured you knew that so I was not going to harp on that.

36 inch away from the front also needs to be clear.

The 30in wide does not need to be centered on the panel, it can begin at either edge of a panel. So a panel can go right up against a corner, for example.Just as long as from that corner 30 inch is clear to the other side.

You can use flexible metal conduit and a junction box to get the panel farther away if needed.

Making bedrooms AF protected is only required in existing homes if you were to do a major renovation to the bedrooms, where walls were built or drywall was removed.

Do a search on the net for surplus breaker vendors, we call them breaker whores. If a breaker is still available from a manufacturer, then the costs are very low. Their purpose in life is to handle obsolete breakers, if you need one of those, get ready to bend over. You will be able to find a GE #THQL2160 fairly cheaper than new at HD.

labman
Sep 1, 2007, 04:57 AM
So there is no way I can make that code compliant without either moving the panel or dryer?

tkrussell
Sep 1, 2007, 05:00 AM
Sorry to be the bearer of bad news, but, you got it. You know me, not here to be popular.

Stratmando
Sep 1, 2007, 05:30 AM
I have had Excellent results with Ebay, Never hurts to look.
Instead of pipe through wall, how about a box meant for generators, that allows plugging in, No leaking of exhaust.

labman
Sep 4, 2007, 09:49 PM
FedEx delivered my plate over the weekend. It looks like it will work. I haven't snapped the main breaker off just to make sure yet. With the breakers I need running about $8 at Lowe's, I doubt it will pay to mess with the net since I only need 2 if I can find a subpanel that will take my old TQP (half size with cross ways contacts) and THQL breakers. It might add up if I found a site that had the breakers, a subpanel, a TVSS, and sold 10-3 with ground flexible cord by the foot.

As for the dryer, I don't think I am going to worry about it. I only anticipate 2 circumstances where any AHJ will be looking at my panel. Some dark, rainy night, when I have the generator throbbing out back and the lights on, I could get a knock at the door. As long as I have a UL approved interlock, I doubt that guy will worry about the dryer being under it. The other thing is eventually selling the house. I suspect such violations are common, and I may not be forced to correct it. If I am, I could go out and buy a cheap, used, stack washer and dryer. One strong argument against living or dying with code violation is that you may be forced to correct them when you sell.

When I count poles in the breaker box, is the 20 max counting the main breaker? Counting it, I have 22 slots. I assume I count both the TVSS and the back feed breaker as 2 poles each.

tkrussell
Sep 5, 2007, 02:54 PM
LM, your secret is safe with us, and the half million other members and guests of AMHD.

labman
Sep 11, 2007, 08:14 AM
Well I am slowly accumulating all the bits I need for my generator hookup. Adding a sub panel to free up room in the main one for the back feed breaker makes a bigger project of it. I spent all weekend at a festival, but did take a side trip to a regional big box store that is much better than Lowe's and HD. I picked up a GE TPL412C 4 slot 125 amp sub panel, a 60 amp breaker, a ground bar kit, a 25' coil of 10-3 with ground, and panel filler strips. Everything but the wire is GE, so listed to be used together. Yesterday I was looking for some 10-4 cord at HD and not finding any. Sure enough somebody came long and asked what I wanted. When I told him, he pulled a full 250' coil of SOOW off the shelf and cut off the 5' I needed. $11.25 plus the end I paid about $16 for. Beats mounting a $50 inlet box up on the side of the house and maybe fishing a wire up through an exterior wall. I still need the #6 THHN wire to go from the 60 amp breaker to the subpoena. Can I use a smaller ground? The bottom of the panel only has 4 knock outs. Can I run more than one 10-2 NM through the larger ones?

tkrussell
Sep 11, 2007, 02:22 PM
A 60 amp circuit requires a minimum of a #10 equipment grounding conductor.

I believe the larger connectors will accept more than one cable. As usual, refer to the data sheet to see if the part is rated to handle more than one cable.

labman
Sep 12, 2007, 08:25 AM
OK, I think I may have seen strain reliefs with more than one indentation for cables. Oh, I guess I need #4 for the conductors with a 60 amp breaker.

tkrussell
Sep 12, 2007, 04:24 PM
No, you don't need #4, you can use #6 THHN for a 60 amp breaker and feeder.

labman
Sep 17, 2007, 12:54 PM
Can I run a cable through the sub panel to get to the main panel? It isn't long enough to go around. That circuit would work better in the main panel.

tkrussell
Sep 17, 2007, 01:04 PM
Yes, just remove the cable sheathing so you only pass the insulated wires pass through.

labman
Sep 21, 2007, 02:14 PM
Well today is the day. I shut the power off this morning and have spent most of the day disconnecting stuff and rerouting cables. I hope to have things far along to have the power back on by dark.

The neutral bar and the equipment ground are all one piece. You would need a hacksaw to separate them. There is definitely 2 different rows of screws, but the one row had both neutrals and grounds. Should I clean that up? Although the box has 20 slots, each row only has 12 screws. Some of them are larger and the fine print specifies how many of what size wires you can use with them.

tkrussell
Sep 21, 2007, 02:32 PM
The older panels never did allow for neutrals and grounds. If I remember this panel has the main in it. OK for the neutch and gnds together, if more ports are needed, get an equipment ground bar, and separate if desired. Definitely more work, but good therapy for those anal, like me.

A well made panel with 42 circuits and all separate neutrals and grounds is something to see.

Best to connect both with a wire jumper.

5:14 and still at it? How is it going?

labman
Sep 21, 2007, 08:04 PM
Well it is dark now, and I have quit for the night. There is still enough stuff connected in the main panel to get by for the night. Trying to untangle a bunch of old #10 is slow going.

The more I think about it, the more I like the idea of using one row for grounds and one row for neutrals. The upper row is all grounds now, and the lower one only has one bundle of grounds in it. Moving it to the upper one will free a large hole for the #6 to feed the sub panel.

tkrussell
Sep 22, 2007, 02:00 AM
I knew I could talk you into it.

tkrussell
Sep 23, 2007, 04:09 AM
Well are you done yet?

No pressure...

What is the chance of seeing some pictures?

labman
Sep 26, 2007, 03:39 PM
The end is in sight. Would it be OK to terminate the neutral of one circuit that passes through the main panel there and the hot in the sub panel? The 2 panels are only separated by a 1 1/2'' offset nipple. I lack about 3'' of neutral to reach the neutral bar at the bottom of the sub panel.

I do have the best pictures my cheap little digital camera takes.

tkrussell
Sep 26, 2007, 04:24 PM
Sure, the neutral is the same, and the imbalance will be negligible.

labman
Sep 29, 2007, 02:59 PM
I decided not to connect that neutral in the main panel, but to save the last neutral port there for the TVSS I plan to add. I saw I could move the other end from one 4'' box to the one above it I recently added, gaining 4'' which is more then enough. When I added the upper box, I ended up with so much wire in the lower one, I had trouble getting the cover on. Remember, I am still fighting the coil of 10-2 I was given 30 years ago. Originally I had the feed connected to line terminals of a GFCI outlet and another duplex connected to the load side over my work bench. Later I have daisy chained the those outlets to two more in the garage. To avoid unplugging one and plugging in the other every time I change the tool I am using, I recently added another 4'' box and 2 more duplex outlets.

Electricity is like dogs, the more I learn, the more I realize I didn't know. I had connected the 2 boxes with a strain relief, run NM singles and ground wire through it and tightened it up. Is that right? Should I use an all thread nipple, nuts, and bushings? Run screws through the little holes next to the knock out? If I do that, do I need some kind of a bushing in the knockouts?

Could the full moon explain some of the recent answers here? # 6 for 125 amp service, #14 in a 20 amp service, and the obsession with switch loops? I am glad I have somebody that knows more than me here to come to for help.

tkrussell
Sep 30, 2007, 04:19 AM
I had connected the 2 boxes with a strain relief, run NM singles and ground wire through it and tightened it up. Is that right? Should I use an all thread nipple, nuts, and bushings? Run screws through the little holes next to the knock out? If I do that, do I need some kind of a bushing in the knockouts?

Sorry I am not understanding what your referring to.

labman
Sep 30, 2007, 09:33 AM
Likely I confused things with too much detail. I have 2 of the 4'' x 4'' boxes mounted one above the other. How do I fasten them together, and do I need to protect the wiring where it passes through to the second?

tkrussell
Sep 30, 2007, 12:45 PM
Ahh, OK, better put.

Yes the wires need protection from the sharp metal edges, so you can use a close nipple with two locknuts and bushing at each end, or if the boxes are directly next to each other, use a Chase nipple one locknut and bushing.

labman
Sep 30, 2007, 02:36 PM
I don't think I will plague the electrical supply with buying one 1/2'' Chase nipple. They may only come in boxes of 50. I doubt the big box stores have heard of them. I will use the plumbing short nipple that was the best the Ace hardware could come up with. So many little details to getting things right.

labman
Oct 5, 2007, 07:56 PM
All right, the furnace ran off the generator. This project is finally winding down. I have the covers back on both breaker boxes, and the interlock works. I set the box and spliced the NM-B to the flex cord. I shut everything down but a few lights and made the switch and fired up the generator. I then turned the furnace on, and it fired right up.

I still have a lot of details to finish up, adding locktite to the screws holding the plate now I know it works, the all important UL approved stickers, posting a new list of breakers, some drywall repair, and on and on.

The furnace is properly tied to the house wiring, hot, neutral, and equipment ground. The generator is properly tied in, 2 hots, neutral, and ground. I checked and I had 116 volts on the one leg under light load. Forgot to check the other leg. Since it worked on first try, it gives no clue to other's problems. I suspect the 116 volts might drop under a heavier load, but still be higher than many have coming in from the power company. I checked that the other night, 122 volts. Note, using a Sears 982017 Multimeter.