Ask Me Help Desk - Shed and generator wiring

I have read a good deal and appreciate the help. I still have a couple of things that need clarity.
Details: I have an outside breaker box just beside the meter pan with 200A mains for 120/240 VAC 200 A service. There are 8 spaces available and two are currently filled with a shed breaker, a double 30A. This was added 23 yrs ago at the insistence of the power company since my original service panel had the mains in it inside the house. I wanted to add a carport and was told that the service entrance had to be moved since the incoming service could not be over a roof. Luckily, the service was on the N side of the house near the corner and had to be moved just around the corner to the W side, only about a 5 ft move. I chose to bring the service from the nearest pole underground. It was previously overhead. So far - POCO to underground wiring - up to panel with mains and 8 spaces for miscellaneous breakers - around the corner through metal conduit to inside panel with , again 200A mains and forty spaces GE 200A panel from 28 yrs ago.

Q1) shed wiring - The outbuilding is about 50 ft from the house and was reached with 10-2 with Ground direct burial cable. From a double 30A breaker in the outside breaker box. The problem there is that it is attached to a double 30A breaker in the outside breaker box essentially picking up 120V on each of the white and black leads. (My 240V water well is wired the same way on a 10-2 + bare Gr). The two hot leads supply a sub panel in the shed and are split into 2 separate 120V circuits. I have no equipment in the shed requiring 240V. Table saw router etc all run on less than 20A and 120V. SO... should the shed sub-panel be rewired (both ends) from a single 30A breaker in the house outside breaker box employing the buried cable 10-2 w Gr and have one 30A 120V circuit in the shed? I believe that I should get a sub panel for the shed that does not "bond" neutral to ground and that an additional ground rod at the shed is acceptable but not necessary. Is such a sub-panel available where GR and white neutral are kept separate?
Q2.) The water well is self grounding is it not? So is the 3-wire cord going 50 ft to the water well OK?
Q3) What started me investigating the whole thing is the need to hook up a gen set to the house for emergency b/u. I really need the water well and a few other things (the frig)are luxury. After Katrina we were able to get one TV station via satellite and it was great to know what was happening. We were without POCO for 2 weeks and I live about 80 mi from Ground zero. I have a 5550 watt gen set with 8700 surge watts. The inside breaker box is recessed into the wall and full so I believe the outside breaker box is the likely candidate for an Interlock Kit. I have read about removing the bonded neutral and floating it on the gen set and have instructions for my particular gen. It should be easy and I will ideally toggle it and mark the positions. I want to use a power cord to reach 20 ft to a power inlet and believe 10 AWG is enough. (Q3-A) Is a 10-3 w Gr required here ? Or is 10-2 w Gr OK. (Q3-B) Is it safe to use a grounding rod (already in place beside where gen sits). From the inlet box to the outside breaker box where Interlock Kit will install, it is about 30 ft and I have some 8-2 w gr solid wire. (Q3C) Do I need a 4th wire to serve as insulated neutral or ground and if so, would a single insulated awg 10 be adequate since I'm on a 30A circuit? Is it necessary to run a Ground if gen frame is tied to rod as is the main panel?
This is all less than ideal but with inside breaker box recessed near a kitchen corner, I do not want a surface mount transfer panel and even less want to start tearing out sheetrock below the panel to drill holes in the bottom plate for more wire. It is a raised house so the possibility is there. The outside breaker box is exposed to weather so the Interlock Kit seems ideal.
Thanks, curlie.

Your "couple of questions " has a great deal of detail to go through, I am sure this is why the delay getting an answer to you. Plus the questions are a bit muddled.

Q1) shed wiring - The outbuilding is about 50 ft from the house and was reached with 10-2 with Ground direct burial cable. from a double 30A breaker in the outside breaker box. The problem there is that it is attached to a double 30A breaker in the outside breaker box essentially picking up 120V on each of the white and black leads. (My 240V water well is wired the same way on a 10-2 + bare Gr). The two hot leads supply a sub panel in the shed and are split into 2 separate 120V circuits. I have no equipment in the shed requiring 240V. Table saw router etc all run on less than 20A and 120V. SO..... should the shed sub-panel be rewired (both ends) from a single 30A breaker in the house outside breaker box employing the buried cable 10-2 w Gr and have one 30A 120V circuit in the shed? I believe that I should get a sub panel for the shed that does not "bond" neutral to ground and that an additional ground rod at the shed is acceptable but not necessary. Is such a sub-panel available where GR and white neutral are kept separate?

The 2 wire cable to the panel is wired wrong, needs an insulated neutral in addition to the bare equipment ground, for a 120/240 volt feeder.

Using the bare for neuteal and ground is wrong.

Using the 2 wire cable for the pump is fine, as it only needs two hots and ground.

If you change the panel feeder to a 120 volt, then it will be fine with the hot, white neutral and bare ground. But what can you do with it? Use it for a 30 amp device. Cannot feed 20 amp receptacles.

You can connect the #10-2+Gnd cable to a single pole 20 amp breaker and use it for 20 amp receptcles.

Any subpanel must have an insulated neutral wire and neutral bar, separate from an equipment ground conductor and ground bar in the panel. A subpanel in a separate building must also have at least one ground rod grounding the equipment ground bar.

Unless your going to replace the feeder cable to the shed, I don't see you being able to install a properly wired subpanel.

Q2.) The water well is self grounding is it not? So is the 3-wire cord going 50 ft to the water well OK?

Yes, two hots and bare ground is correct for a 240 volt device.

(Q3-A) Is a 10-3 w Gr required here ?

Yes.

Q3-B) Is it safe to use a grounding rod (already in place beside where gen sits).

Yes, if the manufacturer of the genset instructes the frame to be grounded, best to use the existing rod.

From the inlet box to the outside breaker box where Interlock Kit will install, it is about 30 ft and I have some 8-2 w gr solid wire.

? What is the #8-2 for?

(Q3C) Do I need a 4th wire to serve as insulated neutral

Yes

would a single insulated awg 10 be adequate since I'm on a 30A circuit?

To connect to the rod? No must be min #6 wire.

Is it necessary to run a Ground if gen frame is tied to rod as is the main panel?

Follow the manufactuers instructions.

The outside breaker box is exposed to weather so the Interlock Kit seems ideal.

The interlock works good, simple to wire.

Go through some diagrams here:

Gentran Corporation: Generator Transfer switches for home & business

May help you understand better how to wire the grounding and neutral.

Go through this, and if you have any additional questions, list them separately and logically.

It was a lengthy description but got an answer instead of questions for more info needed. Thanks, TK. -
RE: Shed: I did mention the shed had a sub-panel with two 20A 120V circuits; I did not mention that two 20A breakers are in place in that panel, one for each circuit. I will convert the shed to one circuit, Bl = hot W = Insulated Neut and Bare = Eqt Gr. Neut and Gr will be kept separate by installing another strip in sub-panel and keep grounding clamp to rod in place at shed. Thanks for confirmation on all .

Re: The Gen will hook to a power inlet box via a 25ft cord and male inlet type L14-30. The inlet box will hook to wiring that must travel 30 ft before reaching a backfeed breaker. I have 35 ft of 8-2 w bare Ground (solid) that was given to me. The extra strand of wire that I think I need will run along with the 8-2. I suppose the best thing to buy is a single strand of RED since the 8-2 contains BL & W. I intend for these wires to carry 2 hots Bl and R along with a Neut Wh along with Bare Ground from the 4-wire power inlet to the backfeed breaker, some 30 ft. Since I already have the 8-2 w Gr all I might need is a single cable capable of carrying 30A since the gen plug (output), the inlet power receptacle, and the backfeed breaker are all rated for 30A. The questions are will the size 8 conductors fit into the L14-30 device (gen power inlet) and will the extra Red conductor need to be the same size as the 8-2 conductors? Theoretically, #10 should carry the load, but I am using #8 since I have it.
Thanks, curlie jones

Post Reply to same thread to keep it all together. I merged the two posts.

So you plan to conver the 240 volt #10-2+Gnd to a 120 volt feeder, and keep the subpanel with two single pole 20 amp breakers?

The only way you can do this is to jumper both hot feed lugs with the live 120 volt wire. This is not proper, even thou it has been done before. I have seen worse done, do this at your own risk. I cannot give my approval, thou.

Adding a wire on the outside of a cable assembly is not allowed also.

Again, been done before, I have seen worse done, but cannot give approval.

The datasheet, and/or labels on the device will tell you what size max wire can fit in the terminals.

While this may be temporary, and you need to do what you need to do, you really should make up a proper cord to run from the genset to the power inlet.

Re: Shed I will not need to "jumper" anything since I am changing the 10-2 feed to a single 30A breaker at its source, the house main. The wire will carry 120V and be capable of 30A, hooked to a 30A breaker at the house panel (outside box with mains and a 30A branch breaKer) to one side of the buss. On the terminal end, it will be hooked to one 20A breaker in the shed. The other 20A breaker in the shed will no longer be in use. The receptacles in shed are 20A; the wiring to them is 12-2 w G. I will have one circuit I hope properly done, where there were two. If there is any error in this, I am still not seeing it.

Re: Generator - I will buy a "proper" cord that is weather proof and has 3 #10s and a ground. The cord you question is the one running under the house that is made up of 8-2 w Ground + another single insulated conductor that I will color designate as neutral. This runs from inlet box to the backfeed breaker. The question was re: this single cable. Can it be #10 stranded for a neutral? Can it be #8 stranded? The gen to house inlet will all be #10 with 3 + gr. a commercially bought cable with weatherproof ends, though gen sits under carport. The wire from gen power inlet box to backfeed breaker will be under the house (restricted crawl space , house is on block chainwall with one access point closed off. I can put the 8-2 + other cable in conduit if that would help but all the house romex is stapled to joists beneath there with no runs in conduit.
Thanks, Curlie

Nothing wrong with the feeder, good to use the #10-2 cable for a 120 volt feeder. Why not just install a 20 amp breaker at the Main Panel? Otherwise your plan is fine.

Adding a wire on the outside of a cable is not allowed for permanent feeder. For temp, OK but needs to be changed out. #10 is fine for the neutral. Keep in mind, a neutral is current carrying, and should not be outside of a raceway. So your idea of running separately on the outside of the #8-2 cable is just not proper.

I guess, then, the idea of "temporary" comes into play. If this is hard-wired to a power inlet box and fastened in place "temporary" could be a misnomer. On the other hand, if it is wiring energized with an extension cord and used if/ when there is a major outage, the wiring can still be considered permanent, just simply not in use most of the time.

Re: shed - TK sez "Why not just install a 20 amp breaker at the Main Panel?" Because I have read in other threads that a separate structure required its own panel as a sub-panel of the main panel, wherein neutral and ground are kept unique and not bound in that sub-panel.
Since I will end up with only one 20A circuit in the shed, I thought about taking the white neutral from the 10-2 (feedwire) and wire-nutting it in the sub-panel to the beginning of the daisy chain of four outlets already in place. I only have one terminal bar that has both grounds and neutral on it, but remember that I will go to only one circuit. Therefore, Incoming feed wire is 10-2 w Gr hooked to grounding terminal. One daisy-chained circuit with one ground hooked to same terminal as the feed ground. One other ground wire going to ground rod just outside this wall hooked to same bar, making sure the grounding terminal is not isolated from the box that contains it. ZOne terminal bar with 3 wires.
For neutral, however, there is only one white feed and one white neutral at the beginning of the chain of outlets. Is it considered acceptable to wire nut those two wires inside the breaker box?

Quote:

Originally Posted by curliejones

I guess, then, the idea of "temporary" comes into play. If this is hard-wired to a power inlet box and fastened in place "temporary" could be a misnomer. On the other hand, if it is wiring energized with an extension cord and used if/ when there is a major outage, the wiring can still be considered permanent, just simply not in use most of the time. ?

I am trying to give a little here if it is temporary, but if the cable will be considered as permenent, then a new 4 wire cable needs to be installed, and not do the add the neutral wire on the outside of the #8-2 cable.

Quote:

Originally Posted by curliejones

Re: shed - TK sez "Why not just install a 20 amp breaker at the Main Panel?" Because I have read in other threads that a separate structure required its own panel as a sub-panel of the main panel, ?

A separate building needs a disconnecting means at the point of entrance of the feeders, this can be the 20 amp breaker you have in the subpanel, or can be a single pole switch, with the circuit protected by the single pole 30 amp breaker at the Main Panel, that I am suggesting to be a 20 amp breaker.

Quote:

Originally Posted by curliejones

Since I will end up with only one 20A circuit in the shed, I thought about taking the white neutral from the 10-2 (feedwire) and wire-nutting it in the sub-panel to the beginning of the daisy chain of four outlets already in place. I only have one terminal bar that has both grounds and neutral on it, but remember that I will go to only one circuit. Therefore, Incoming feed wire is 10-2 w Gr hooked to grounding terminal. One daisy-chained circuit with one ground hooked to same terminal as the feed ground. One other ground wire going to ground rod just outside this wall hooked to same bar, making sure the grounding terminal is not isolated from the box that contains it. zOne terminal bar with 3 wires.?

The one bar you have in the panel will need to be considered as the equipment grounding bar, that can accept all the bare grounds, the grounding electrode conductor, and must be connected to the panel box using a green machine thread screw or a jumper wire. The bar as it sits now is probably set up as neutral bar, with insulating mounting feet.

Quote:

Originally Posted by curliejones

For neutral, however, there is only one white feed and one white neutral at the beginning of the chain of outlets. Is it considered acceptable to wire nut those two wires inside the breaker box?

Sine the one exisitng bar will act as the equipment grounding bar, and you only dealing with one circuit, then yes you can splcie the feed neutral to the branch circuit neutral in the panel.

Is the mud getting clearer?

Very Clear, TK! Thanks for your help! The shed was rearranged to follow suggestions and is all on one 20A circuit and hopefully, much safer! I am gathering the pieces/parts for the gen power install and hope to ward off hurricanes by being ready for an outage. You just never know what will happen. Six inches of snow came to Roseland, LA on my birthday last year, causing an outage for several days.
Curlie