Need 220vAC electrical help - change 4 prong outlet to 3-prong

[C4Ranch]

Thanks guys! Gonna do it this way:
14-50P -> 6-50R
Ground to Ground
Hot. to Hot
Neutral ignore. :thumbsup:

 

[Sodo]

I'm still not convinced that my old generator (3-wire) is instant death. Nor my new generator that has a 'switched neutral kit' that allows me to choose the application (3-wire or 4-wire).

But as several of you say, the NEC is there to protect those with thick skulls from themselves. My skull's pretty thick, but it has to be, to weed out the bad info its bombarded with, often from forums. Give me some time. I do appreciate knowing the reasons behind NEC code.

What do you guys think of this "Switched Neutral Kit" which professes that 4-wire is to allow GFCI protection to function correctly? (from post #7) My shop has no GFCIs, I'm powering welder & shop tools.

And, beating a dead horse here, unplugging my 3-holer restores the 4-wire unbounded neutral to original. Same as if I bought this adapter Miller 300517 (as recommended by several folks including Bukitcase.


If the ground path happens to be thru my thick skull there will only be a slight tingling and I may live to post again.

 

[ModMech]

I am NOT an electrician, but my FIL is a recently retired 30+ year Journeyman electrician and lead and he has made it ABSOLUTELY CLEAR that the neutral and ground MUST NEVER BE CONNECTED except at the panel or inside the "appliance" if designed to be so.

One of the major reasons for this is of course safety, current code REQUIRES a 4 conductor receptacle, this is to ensure that all connected devices will operate as designed (some will not on a 3 conductor). Everyone encountering a 4 prong receptacle will expect it to be wired correctly and safely, so wiring it differently than NEMA standards, opens the possibility for serious problems.

If the appliance has a 3-pole cord, you NEED a correct 3-pole plug and receptacle, if it requires only a 2-pole connection and all you have is a 3-pole, do not make the connection to the "extra" terminal as others have also suggested. In this way, nothing bad will happen.

From my limited experience with wiring, it seems you have made a 2-pole connection with a 3-pole plug, no one but you will expect that.

Reference: How to wire 240 volt outlets and plugs

 

[robstaples]

What is your old generator? Do you just mean the 3 conductor extension cord? All this discussion of ground and neutral means almost nothing with an ungrounded generator. It's an isolated system. Meaning ground is not connected to the generator in any way. But tools have grounded cases(3 wire 120 plug) and welder frames connected to the green wire. So it can impact the safety as to how or what one connects to the green wire.
There are standards and good practices that have been established under the NEC, that if followed, makes for as safe as one can expect wrt electricity.
If your answer is about 3 conductor-- 2 hots and combined neutral/ ground wire, it will work fine and if the generator is never grounded, it is also fine.

Grounded systems use a isolated ground ( green wire) from the load carrying wire-the neutral or white wire.

 

[Sodo]

Old generator is a 120/240v 5kW Coleman from about 1985. It has a 3-wire outlet. No evidence suggests it killed anyone including me but maybe we were all lucky. New generator (2014) has 4 wire outlet.

Problem with this thread is, I proposed a modification, was advised wrong (use 2 hots & ground, isolate neutral). 240v seemed fine but 120v didn't work, so I suspected something was wrong. I read more into post #7 (DaveM7040) and changed accordingly to a selectable Neutral-bond. Now the 120v outlets (and the 240v) work on my extension cord. And the generator is restored to original by unplugging the bonded-ground plug.

It's currently wired per post #22 and I think its all good. If anyone is to offer further advice please refer ONLY to post #22 otherwise we're going in circles & putting bad info on the TbN forum.

I think the only remaining question is whether a 120v tool, with a grounded metal case is used on the one leg (a 120v outlet on 120/240v ext cord) poses significantly more danger than it did for 30 years on the 1985 Coleman.

 

[robstaples]

No higher risk today than years ago. I understand. Be safe, I need your wisdom on B series. Rob

 

[Sodo]

Wisdom,,,,good luck with that- once Terry's tapped out (post 33) you can bet I'm runnin on fumes.

 

[Big Barn]

...we're doomed.

 

[Mark @ Everlast]

Here's all you need....Welder approved. lol Adapter Cord - 14-50P to 6-50R 230V 8/3 Cable 1.5' Long (For Champion ELITE & Champion 10,000 Welder/Generator) - Hobart Welding Products

 

[Gary Fowler]

All this advice flies out the window when wiring up a 50 amp 4 prong service for a camper. Many an electrician has fried camper internals when wiring them up as a 240V system. The are supplied with two 50 amp 110V circuits when properly wired but they look like 220 volt 4 prong plugs.

If you plan to run your camper off a generator with 220v power DONT DO IT. There are lots of YouTube videos on how to correctly wire up a RV plug.

 

[LittleBill21]

All this advice flies out the window when wiring up a 50 amp 4 prong service for a camper. Many an electrician has fried camper internals when wiring them up as a 240V system. The are supplied with two 50 amp 110V circuits when properly wired but they look like 220 volt 4 prong plugs.

If you plan to run your camper off a generator with 220v power DONT DO IT. There are lots of YouTube videos on how to correctly wire up a RV plug.

50 AMP service is 240v in an RV. It is the 30 AMP service which is 120v that gets mis-wired to 240v

 

[Deere Dude]

50 AMP service is 240v in an RV. It is the 30 AMP service which is 120v that gets mis-wired to 240v

Sometimes it only fries microwaves. Don't ask how I know.

 

[Deere Dude]

50 AMP service is 240v in an RV. It is the 30 AMP service which is 120v that gets mis-wired to 240v

Sometimes it only fries microwaves. Don't ask how I know.

 

[LittleBill21]

Sometimes it only fries microwaves. Don't ask how I know.

i don't know what this even means, there is nothing different between residential 50amp 240 and rv 50amp 240. if your saying your micro got fried, you had a problem, either a loose neutral or something else.

 

[Deere Dude]

Sometimes it only fries microwaves. Don't ask how I know.

i don't know what this even means, there is nothing different between residential 50amp 240 and rv 50amp 240. if your saying your micro got fried, you had a problem, either a loose neutral or something else.

No, I meant that a close friend wired a 30 amp camper plug to 220 breaker panel not considering it was a 120 volt plug. They look like 220 plugs but are actual 110. Has nothing to do with 4 wire. He turned on his microwave and burnt the control panel in the microwave.

 

[LDCravey]

Ok, I am going to attempt to make things "clear as mud" regarding tying Neutral to Ground at the far end of a generator or electrical panel. I realize that 99%+ of everyone has very limited formal electricity or electronics training or background, but here goes.

The reason many of you are still alive today is that before the NEC was changed to requiring 4 wires (hot, hot, neutral & ground) you may have received slight electrical shocks when touching the case of an electrical appliance. The primary reason you are not dead now is that the electrical shock was very very dependent on how much current (amperage) was flowing on the (safety ground) AND how long a wire was required to go back to the electrical panel AND the wire gauge (electrical resistance) of the wire that went back to the electrical panel. All 3 factors determined if you got a very slight shock, a mild shock, a strong shock or you died.

* If the wire to the electrical panel was very short and, (let's say), 12AWG, then you may have received a very slight shock.
* If the wire to the electrical panel was very long and, (let's say), it was 14AWG, plus a 100ft+ extension cord, then you may have received a mild to strong shock.
* If you used several 100ft lengths of (let's say) 16AWG extension cords and the AC outlet was another 150ft of 14AWG wire from your electric panel (or generator), then you are probably not around any more to read why you died.

For those of you that have no thorough understanding of electricity, or amperage, or electrical resistance or voltage or wire length, then, you were fortunate that the NEC was changed to let you live a little longer.

Don't be stupid. I know many of you are saying, "Hey, it works, therefore it must be OK". Pay attention to some of the people in this post that are just trying to provide a little education and keep you alive. We do not expect you to fully understand all of the technical reasons, but just remember the next time you get shocked, you might be dead and not here to post a response that says "Yep, I was stupid and ignored the warnings."

I hate to be morbid, but wake up and realize that just because "it works" does not mean it is safe. You (or someone in your family) can be seriously injured or die from incorrect wiring practices and it is possible that you could also be sued by your incorrect wiring practices if someone else gets injured.

Wire it the way you want. I hope you live long and prosper by taking some of our advice.

 

[zzvyb6]

OK, here's what I learned and have implemented for using my Honda EU6500IS:

The manual states that the frame is NOT grounded. The frame has a ground lug to be connected to Terra Firma with a cable and a spike at least 2' into the earth.

You can test to see if a/the generator is grounded by checking the resistance between the ground slot and the neutral slot (the one on the left as you face it) on the 110v receptacle on the generator with a meter. If they are connected the resistance will be zero.

Connecting the 'four prong plug' to a 3 prong RV cable takes a special prong plug (available from Honda or others) that engages only one side of the 220 outlet, the neutral, and the green ground slot. Thus, one of the pins will be missing. This plug looks like a standard 4 prong twistlock plug but only has 3 prongs and uses only one of the 110v pins for the 220 generator outlet to provide 30 amps at 110v to an RV.

"Grounds" only carry "fault" currents. These fault currents usually occur in the generator head because a winding leak forms from age, overload, mice or cheap parts.

"Neutrals" are designed to carry currents as per normal operation.

Neutral is white as a standard.
Ground is green as a standard.
Black and red are usually the +110 and -110 current lines.

If it is necessary to ground the generator to neutral for 110v operation, you can buy or make a plug for one of your generator's 110v outlets that ties the bottom (round) pin to the wider left side neutral.

My Winpower 50kw 220v pto generator has only a 3 slotted range receptacle for connectivity. The plug shows neutral and the two 110v hot lines.

 

[Sodo]

Resurrecting this thread because I have to run a 3wire 240v compressor off my Generator. I can buy all the plugs etc and make ay-dapters, but that stuff is hours away. I wanna use what I have on hand.... which is put this 4-wire plug on a 3 wires cord, plug it in, and compress air ----->Now.

SO....... Green wire is in G, White wire is in W.

I suppose to bond it within the plug - I simply choose X or Y for the black, and jumper across from X to Y? It can't be any other way, but just wanna check first. Sometimes just a little delay is best.

 

[Mark @ Everlast]

No. Don't bond. Omit. You've got to have red/black opposite of each other. Looks like you have the red hot in the neutral position. Red and black should be next to green. Neutral would not be used for a 240V compressor. If you were running to 120V circuits then you'd need neutral I suppose, but not if the compressor is 240.

 

[Sodo]

No. Don't bond. Omit. You've got to have red/black opposite of each other. Looks like you have the red hot in the neutral position. Red and black should be next to green. Neutral would not be used.

OK thanks. The wire colors are White Black Green. The "white" wire is faded (to look like red in the pic).

SO.... What you are saying is ---- black and white (the two hot legs) must be across/opposite each other? If thats the case then GWXY does not help me. What if you look at the prong end of the plug? What is the prong with the "hook"? If that is either neutral or ground, then across is the "other" cross pair. So my hots go on the OTHER two prongs. Is this right?