Electricians: Wiring of a 240v Plug, something is wrong

[Cos]

I am not sure what is wrong here.



this is what I was expecting, however I get:

Line to line (hot to hot) I get 120
Hot to neutral I get 120
Second hot and neutral I get 240



Besides the electrician, 8 years ago, wiring this wrong. What else could cause this?

[danno]

one of the lines is the neutral white wire and the neutral is one of the lines, take plug apart and redo

[Cos]

Yup, so took the panel apart and took a look. Red/Black go to the breaker, good. White to the neutral bus bar. Ground to ground bar.

Open plug. Black and white are reversed.

God dammit, 8 years and no one noticed this? The amount of time and money I have spent trying to fix a dryer just to find out some idiot wired it wrong.


Sorry a little frustrated. I know it is my fault too. When I checked the plug for voltage I saw 120/120/240 so I was happy. Never checked which plug was which.

Funny enough the only B I got in school was electrical fundamentals and I got a B because the start/stop was wired improperly on purpose. I never thought to check it. Seems I am doomed to repeat the same mistakes over and over.

Thanks Danno!

[danno]

no prob, simple fix.

[eblend]

Since your question is answered I figure I will hijack this thread with a related question. I am going to be putting a 240 volt jack in the garage, for possible future equipment. I never dealt with 240 volt before, but when I looked, there appears to be like 5 or more different types of plugs you can use for 240. Is there a standard to this? Which type of plug should I be putting in? I am dealing with 30A here.

[Cos]

^^ I think it would depend on what you are hoping to run. A welder would run the locking 240v plug where as a dryer would run the style of plug that I have shown above.

[m10-power]

Plug configs are based on current. Need to know what your plugging in to get the right plug. And more importantly the right sized breaker, and even more important the correct wire gauge.

Also cos in your diagram you show 110v from line to ground, you never want that to carry any current.

[Cos]

Originally posted by m10-power

Also cos in your diagram you show 110v from line to ground, you never want that to carry any current.

I didnt draw it, just found it in a rage last night. Lol

[sillysod]

eblend what do you plan on running on 240? Heater? Welder etc?

Best to run a heavier wire #8 or even #6 as you can always run a lighter breaker and receptacle, but can't go the other way.

I ran #6 but it's because I have a 60 amp buzz box in my garage and I wanted to be able to crank it.

Normally for heat etc. #8 and a 40 amp breaker should be plenty.

Typically you would just put a 4x4 box on the wall and then change out the receptacle to a dryer or range one depending on what you are running.

[codetrap]

Well cos, at least you got it all worked out for when I run 240 to my garage for a heater, and a separate circuit for my vaccum so I stop tripping the damned thing. I was debating doing that this coming weekend on sunday. Figured I'd just run it using conduit so I didn't have to string it through the walls.