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Nobadays
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# Posted: 6 Oct 2019 21:02
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I moved my generator to it's new location and finished the wiring today. The issue is with a second 12/3 line I ran to power three receptacles- either side of the back deck and one on the deck where my workbench currently is. Everything works, the 30amp to the inverter and the 12/3 runing to the receptacles except when I test the receptacles my widget says the common and hot are reversed.

So here is the wiring run down. 30amp outlet from the generator supplies 120v power to a 60amp 240v square d panel. I removed the 60amp 240v breaker and replaced it with a 30amp and 20amp 120v breakers (single pole I think they are called.) I then put a jumper between the 120v in and the other input to move 120v power to the 20amp breaker. All grounds went into the ground buss bar and all white common wires were tied together. A 10/2 from the 30amp breaker goes directly to the inverter... no issues there I can see. A 12/3 cable with both the black and red wires tied into the output of the 20amp breaker go to the first receptacle. At this receptical the red wires are tied together and pushed back in the box to carry power on down the line. The white common wires are connected to the white side of the receptacle the black to the hot side, all grounds tied together. A junction box 10' along the run is where the red hot line is now connected to the black hot going up to a receptical at my workbench. White commons and grounds all tied together. 16' further along the run the white common enters the last receptical on the common side, the black on the hot side and the red hot is folded and taped for a future run.

I can't see what I did wrong here... yet my tester says the hot and common are reversed. Does this have something to do with the jumper at the breaker box? Am I missing something? Any help will be appreciated!

Thanks guys and gals!

darz5150
Member
# Posted: 6 Oct 2019 22:14
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Quoting: Nobadays
Does this have something to do with the jumper at the breaker box?

That would be a good place to start. Disconnect it, then check the problem.
If that doesn't work, I would back track and disconnect each breaker/circuit one at a time.

darz5150
Member
# Posted: 6 Oct 2019 23:07
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Here's another way to look at it. You need to get 1 outlet to test correctly. Then add other circuits 1 at a time till you find the faulty one. If you can't get one to work. Then the problem is upstream from your breaker box. Meaning how you have power coming in from your Genny.

old243
Member
# Posted: 7 Oct 2019 09:02
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I think darz is correct. Start at the generator , if it has correct polarity. Then work down the circuit. until you find the problem. Make sure your tester is giving you the right info, as well. Good Luck old243

Nobadays
Member
# Posted: 7 Oct 2019 09:17
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Good advice... I'm beginning to think it originates at the generator. Just not sure how to check the 30amp plug on the generator. It does have 15amp outlets, I'll start there. Just thinking, I don't have a ground on the generator right now after moving it, that might help...?

Is there a way to check for reversal of common and hot with volt ohm meter?

Thanks!

Nobadays
Member
# Posted: 7 Oct 2019 14:09
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Ok still chasing the problem. I decided since the only thing I didn't wire was the 30amp pigtail from the breaker box to the generator. When I took the plugin apart it looked to be wired correctly but I switched the hot and neutral for the heck of it.... when I started the generator and kicked the 20amp breaker for the receptacles, this caused an immediate fault at the generator and it shut power off. The breaker did not blow. I switched the hot and neutral back. Fired up the generator and at all my receptacles I still read that the hot and neutral are reversed. No surprise as I changed nothing.

I added a picture so you can see how the breaker box is wired. The problem with removing the jumper from the 30amp to the 20amp side is then I would lose power to that breaker and consequently to all receptacles on the circuit. That won't help.

I took apart the first receptacle to see if it was correct and it is. Plus, the reds are tied together and only fed one of the three receptacles so even if the other 2 were reversed, that one should be correct, but it's not.

Pulling my hair out here! It's not like I'm new to electrical work, I've wired one home completely and numerous remodels and workshops over the years, not to mention just installing our solar system on the cabin. I'm baffled!

Thanks for ideas!
IMG_4925_resize_14.j.jpg
IMG_4925_resize_14.j.jpg


darz5150
Member
# Posted: 7 Oct 2019 15:00
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Try and unplug the 30 amp plug. Then use your tester on 120 outlets on the generator. If it is correct then go downstream. Plug the 30 amp back in.
I hate to suggest this but go to the first outlet and reverse the wires. If it works and you have correct polarity and voltage. You can use your own discretion as to leave it or continue your quest.

toyota_mdt_tech
Member
# Posted: 7 Oct 2019 15:25 - Edited by: toyota_mdt_tech
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Quoting: Nobadays
I added a picture so you can see how the breaker box is wired


OK, I see what you are doing. Feeding it with 110VAC and running 2 circuits Do I see 2 wires coming off one breaker?

ICC
Member
# Posted: 7 Oct 2019 15:48
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If you have not already tried testing with only the black connected, or only the red connected I would do that. One step, one change, at a time moving downstream.

Nobadays
Member
# Posted: 9 Oct 2019 10:07
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Darz.... yep tested the standard outlets on the generator and the are not reversed.... assuming the 30amp is not because when I reversed hot and neutral the generator immediately let me know.

Toyota... yes feeding 120vac from the 30amp generator outlet to 30amp side of this normally double pole 60amp 240v breaker box.... then jumper from that side to the other side to feed the 20amp breaker. Yes there are two wires into the 20amp breaker.... the yellow romex is 12/3 so the black hot is feeding 2 receptacles, the red hot currently 1 receptical but in the future I will extend the red hot to another outside receptical at the front of the cabin.

ICC.... good idea, that will be next. I will pull the black hot out of the breaker and check the receptacle for the red hot, then vice a versa.

I am considering making up a 3 prong cord to power the 20amp breaker off the generator's standard plugin. This would eliminate the jumper wire.

Thanks for the help! On going......

Nobadays
Member
# Posted: 9 Oct 2019 14:54
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Giving up.... I have a neighbor who is a retired electrician I'll see if I can interest him in this dilemma.

Here is what I did today. I tried each of the hot legs - red/black independently to no avail, still wrong polarity. So thought maybe reverse hot and neutral in the box.... generator told me right away that wouldn't work. So made up a pigtail to plug into the 20amp receptacles on the generator allowing me to disconnect the jumper from the 30amp side to the 20amp side... so feeding the 20amp independently from a different plug on the generator. Neutral to neutral, hot to bus bar for the breaker and ground to ground busbar. Still registering reversed polarity on all receptacles. Even changed out the 20amp breaker for a different one. Took another look at the 1st receptacle... it is correct and regardless that shouldn't affect the 1 receptical off the red hot line.... I will take a thorough look at all receptacles this afternoon as I'm sure if one is reversed it would affect the rest...

Thanks again you suggestions!

toyota_mdt_tech
Member
# Posted: 9 Oct 2019 14:58 - Edited by: toyota_mdt_tech
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You know many generators don't have a hot and a neutral, just 2 hots at half voltage (peak voltage, and gets you full voltage peak to peak). I wonder if this is your issue. If you use one of those 3 light testers, you will not get one of the lights.

Nobadays
Member
# Posted: 9 Oct 2019 15:15
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Toyota.... hmmmm.... I have a HF 3500 watt inverter/generator. One of my first thoughts was if this was an issue originating in the generator. When I plug the 3 light tester in the generator it reads correctly. That said it could very well still be the issue. I'm going to check the rest of my receptacles in a bit if the are correct, which I'll be surprised if they are not (and embarrassed! ) , I'm going to write it off unless my electrician neighbor will take a look. I have other work to do.... supposed to snow a little tomorrow and the temp drop to the low teens. Good check on that new buried/insulated water system.... but need to get my winter water system in place and operating too.

Nobadays
Member
# Posted: 9 Oct 2019 17:16
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Took every receptacle out and looked at the wiring, examined the junction box and the breaker box, no where do I have the hot and neutral reversed. I am leaning towards this being from the generator output. I'm just done with trying to chase down this fault when there shouldn't be one.

Thanks all!

1tentman
Member
# Posted: 10 Oct 2019 11:12
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I have been following your post here Nobadays, first Iam going to tell you Iam by no means a electrician, but I do all my own wiring in my cabin and my house. This box you have installed is basically your breaker panel, the black wire coming from the gen is hooked right but shouldnt the commons be hooked to the ground bar with the bare wire. then you should have a ground wire hooked to the ground bar and run to a ground rod. The way you have it wired you are sending the common back to the gen. Look at your panel in your house the common and the ground are bonded together and go to a ground rod. I was reading a article where people are going camping and running their camper off the generator, but they are putting a sure protector between gen and camper when the fire up the gen the surge protector flashes reversed polarity, some will let the current go on thru others will shut it down. They are taking a male plug in and hooking a jumper wire between the common and the ground terminal and plugging that into a extra 110 plug in on the generator,basically bonding the ground and common together and the polarity light goes out. You would be doing the same thing by hooking your commons and grounds together in your box. Like I said Iam no expert just trying to give a differant point of view here I could be totally wrong ,but this will give you something to think about. Good luck with this keep us posted on your results.

Nobadays
Member
# Posted: 10 Oct 2019 11:25
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1tentman.... I see what you're saying, you may be correct here, I'm just not sure. My generator does have a ground lug and as yet I have not driven a ground rod and hooked that up.... maybe with the generator grounded that would help? Possibly a pigtail off the neutral wire to the ground buss? I'm a bit worried if I do that and the generator output is as Toyota suggests (2 hots) I would cause a dead short.

Probably best to start by grounding the generator, as this should be done anyway..... and possibly that ground would help the generator to output correctly...don't know?

Pounding an 8' ground rod into our rocky ground is not something I look forward to! My son in law was here when we did the solar instal and he drove the rod for that system.... saved my arm!

dginney
Member
# Posted: 1 Nov 2019 15:14
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Refer to this post about generators and bonding etc. I think this post will be helpful here:

http://www.small-cabin.com/forum/2_6377_0.html

Nobadays
Member
# Posted: 1 Nov 2019 20:31
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Dginney... thanks for the link. Looked through it but need to study a bit... confusing.

toyota_mdt_tech
Member
# Posted: 1 Nov 2019 21:42 - Edited by: toyota_mdt_tech
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nobadays, I suspect your ground at the generator/chassis is tied to the ground at the plug, but not electrically tied to the generator in any other way. So when you drive a ground rod into the earth, its just bonding earth to the ground lugs at the generator plugs and gennie chassis. Thats all.

To be safe, I would remove the bonding screw in the panel (or leave it out of its not in place) but keep the parts and just tape them inside the panel if you need to bond later. You will run your red and black to the input lugs at the top or to a breaker that will act as a main. Size it to generators output along with wire, ie 30 amps, use 10AWG wire or larger etc. Neutral bar in the panel is insulated, hook your white wire there. Now buy the extra ground bar made for your panel and install it, it will be where you hook your grounds (green or bare wire)

The ground will do nothing unless you hook your generator chassis to a ground rod.

Why do it this way? Most generators dont produce line to neutral of 110VAC, instead, it produced 55VAC peak from each side, while peak to peak is 110VAC. So both sides are producing AC at half. So each side is hot, a volt meter across the plus will show the 110VAC

You can tie it in with a nice inlet plug if you want.

Honda does make a true neutral generator, EB2200i

https://powerequipment.honda.com/generators/models/eb2200i

Nobadays
Member
# Posted: 2 Nov 2019 10:45
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Thank you for even more information! Presently we are back at our primary home in AZ so it will be the middle of December before we are back up at the cabin.

That said, after reading through the other thread and digesting Toyota's comments I think I have a better understanding of what might be going on. I got on YouTube and watched several videos including one that did a great job explaining bonded and floating neutrals. Searching on line about the HF 3500 Predator inverter/generator I think it is a floating neutral.... BUT.... I'm not sure about that as I think (if I remember correctly) I plugged my tester into the generator and it said the circuits were correct... not sure I remember doing that though, can't imagine I didn't check it at the source though.

I also watched another video showing how to test the receptacles at the generator.... basic continuity test between neutral and ground. Another one on how to build an Edison plug to tie the ground and neutral in case that is needed. When we get back up there I will work on it some more and see if I can figure out just what will correct the issues....

BTW.... Toyota... my generator only puts out 120v @ 30amps. The red/black/white wire in the picture of the box is a 12/3 young out to feed two independent- of the cabin electrical - circuits. These will be used for outdoor power directly off the generator. The gray wire on the right is the feed off ghe 30amp, 120v plug, neutrals are all tied together (might be my problem if the generator is bonded) the black feeds the mains with a black jumper between sides.... ground to ground bar.

Presently I do not have a ground rod at the generator.... I will drive one when I go back in December if the ground is not frozen, otherwise in the he spring.

Thanks again for the help!

Nobadays
Member
# Posted: 2 Nov 2019 11:04
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Read back through the thread.... I did test at the generator and all was good there. The other thing I did was build a pigtail to feed the 20amp side independently, took off the jumper... still showed hot and neutral reversed. I'm definitely wondering if it has something to do with all my neutrals tied together. By tieing them together I am I including the cabin circuits on the neutral side.... so there could be an issue in the cabin back feeding the neutral? BTW, the original owner did not drive a ground rod for the cabin electrical so it is not grounded either....

I think I need to get things properly grounded, then resume chasing this problem.

toyota_mdt_tech
Member
# Posted: 3 Nov 2019 11:04 - Edited by: toyota_mdt_tech
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I would separate the neutrals from the grounds including the bonding screw at the panel. I'm certain your generator has no ground, the plug is connected to gennie chassis, thats all and if you drive a ground rod and hook gennie to it, then its an earth ground.

With most gennies putting out half (peak) voltage at each leg, peak to peak is still full voltage, but you might be seeing the voltage on the neutral wire showing the reversed polarity. I used a tester on mine and it just shows an open ground, which I knew.

If you are rated at 30 amps, you want to step up to 10 gauge wire too.

If you are tying that into a panel, you will need to jump across the inputs, use a chunk of 10AWG wire for that too. What make is your panel and how many spaces? If you know the model, you can buy a separate ground bar, it bolts to panel chassis on the inside.

I have the Square D Homeline 12 spaces and it came with a separate ground bar because it was a sub panel, if you have a primary panel, you can buy the ground bar and add it to keep neutrals (white) on existing bar and move all grounds to separate bar that is bonded to panel chassis. If you ever make this a regular primary panel, put bond back in place. (this is a screw or a jumper that ties the neutral bar to the ground bar, its ID as green, maybe anodized etc)

This is the ground bar I speak of, comes in many sized, just get one large enough to hold all your wires, you don't want to double up on them, 1 wire per hole. This would be all your bare wires (grounds) regardless if your gennie is true neutral or a floating ground.

By tying your neutral to ground and not having a true neutral, you may be energizing gennie chassis as its chassis is tied to ground prong at plug (floating) and they want you to hook to earth ground.

toyota_mdt_tech
Member
# Posted: 3 Nov 2019 11:18 - Edited by: toyota_mdt_tech
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Nobadays, OK, looking back at your panel, I see a orange, yellow and white romex, see a 30 amp breaker and a 20. All neutrals and grounds are not bonded to each other in that picture, so looks OK.

Is the orange wire the input? IE 30 amp 110V from gennie? I see a red wire, let me know what wires are inputs and outgoing circuits. I shouldnt see any white romex in there at all with the breakers you have.

If that was my set up (I would get a bigger one, but we will go with this one) you should have your input from gennie (110VAC at 30 amps) should hook to panel input (black wire with 10AWG jumper going to other input like you have) and whites bonded and grounds bonded just like you have them. Gennie input doesnt need to run to breaker unless you want a master disconnect at panel, your gennie have fuse protection. This will consume an extra space which you are in short supply.

The 2 breakers should be your circuits, ie 20A should be hooked to yellow romex, 30 amp remove and add 15A and hook white romex to it. Remove bond inside your patch cord.

Ground gennie chassis to earth ground (but everything will work without it)

Nobadays
Member
# Posted: 3 Nov 2019 13:28
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Toyota.... The panel is a Square-D 60amp 240v double pole A/C disconnect panel. I pulled the 60amp double pole breaker out and put 2 single pole breakers - thus the jumper across the hots at the input. 1 breaker is 20amp and feeds 3 receptacles - outside for power off the ginney independent of the house solar power system. The other breaker is a 30amp that feeds the house distribution panel/via the Inverter-Charger.... code required I have a 30amp breaker between the generator and the Inverter-Charger. The box IS fed by 10 guage wire from the 30amp plug on the generator.

I have since taken the jumper wire off and am independently feeding the 20amp breaker off one of the 20amp receptacles on the generator.... I had tried that to see if it would help with the hot/neutral reversed. To no avail....

I do have all the neutrals tied together as you note and grounds to a bus bar bonded to the box, however no earth ground as yet because I have not driven a ground rod.

The home distribution panel has no earth ground either as the PO did not drive a ground rod for the home circuits. I need to fix that.

My thoughts are that there is a possibility that there is a hot neutral somewhere in the home circuits and since my neutral on the 30amp and 20amp feeds are tied to the house circuits (along with my outside receptacles) I am getting the hot/neutral reverse through there.

Or.... it's just the floating neutral from the generator causing all the issues.

I think my first course of action when I'm back up there is to isolate the outside receptacle neutrals from the house circuit and just tie that neutral directly to the feed from the generator. If that solves my problem then go hunt the hot/neutral reverse in the cabin. If not then I can probably be pretty certain it is the floating neutral from the generator throwing up the code.

Nobadays
Member
# Posted: 13 Sep 2020 13:54
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Resurrecting.... problem solved! As was discussed, this generamust have a floating neutral. The manual specifically says to ground the generator and of course I had not. Recently I buried conduit from the generator shack to my newly built shop. While the trench was open I bent a ground rod so that it could lay horizontally in the trench then stick out of the ground at the generator shack. Then grounded the generator. First start up the generator faulted... not sure why... shut it off and restarted it and it ran find without faulting again. I stuck a tester in the receptacles in the new shop, all were good.... for kicks I checked the receptacles that had before been showing neutral and ground reversed... all good!

Maybe when the manual said to ground before use they meant it?

toyota_mdt_tech
Member
# Posted: 13 Sep 2020 21:17 - Edited by: toyota_mdt_tech
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Nobadays, I have seen many generator schematics and most dont even have a neutral and those that do, dont utilize it for power generation.

I have found there is really no ground on a generator, in other words, the 3rd prong in your plug is hooked to nothing except the generator chassis and if you ground it via an earth ground rod, then its is an earth ground via your rod. Otherwise, its hooked to nothing.

I have to admit, I have never grounded my Honda generator when its hooked into my cabin. But I do not have my white leg and grounds bonded anywhere in the panel or elsewhere (see some jump them together in the patch cord). And my generator chassis is all plastic too.

If I was to plug in one of those test light units, I would get one amber light meaning an open ground.

Glad to hear its a closed issue and thanks for following up instead of leaving us all hang'n.

Aklogcabin
Member
# Posted: 20 Jan 2021 10:56
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What user ?

Nobadays
Member
# Posted: 20 Jan 2021 11:11
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AK.... me thinks a bit of this thread hath been clipped! A spammer had posted. Their addition and those discussing it below are magically gone! Which is fine.

Ushuaya
Member
# Posted: 22 Jan 2021 22:01
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Good thread very helpful

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