my wifes boss is having some additions to his coffe shop which involved upgrading his service from 100 amp to 200 amp.
sounds simple enough but the story behind it gets interesting.

he has a 3 phase delta service with a high leg...gotta admit i know little to nothing about, other then remember reading in nec how it must be orange in color and beleive it must be in the middle of the phases(correct me if im wrong) anyway what i don't understand is the voltage he is talking about, his equipment is 240V and if its a delta high leg with orange marking then i assume(yea yea i know ass-u-me) that the voltage would be 480/277 brown-orange-yellow wouldn't 240/120 be black-red-blue?
he said when the electrician change the meter and installed the new service..he fired up the panel and had breakers tripping and when the electrician took readings at the recepticles he was getting 240V which he told my wifes boss was impossible....so he went though a couple of meters thinking they were surely broken. but after a call to one of his buddies he soon learned that he did indeed have that voltage present at a 120V recepticle and i think we all know what happens to 120V appliances and computers when such things happen. so what does this guy do when a solinoid(110V)fries he tells my wifes boss that his friend who originally wired it with a 2 pole 20A breaker one for the solinoid and the other for a different piece of equipment...that he wired it wrong and it isn't his fault that the solinoid fried. even though it worked fine for four years prior to him getting there.
and the computer he toasted as well from a seperate single pole breaker stabbed into the high leg phase wasn't his fault either.
now this new panel has blanks every third space.
just when you think this electrician couldn't get worse...
he tells them that he would have to charge more to finish the job since the existing meter was 100A (duh) he would have to buy and install a 200A which wasn't included on the original bid since he didn't know he would have to change the meter... and ohh yea the service wire too. so add on another $1500 to

please explain the high leg delta and any comments about this electrician would be appreciated.

thanks,
h20

Red leg delta is basically just your garden variety 120/120 center tapped service with another transformer (rarely 2) connected to provide the 3d phase. If you are starting around the triangle from the center tap the 3d leg will be 208v away.
It is the electrician's fault if he connected any line to neutral loads to this leg.

As far as I know, the high leg should be on the far right socket of the meter, for metering and then should be on the center (B) phase of the service disconnect or panel.

A coffee shop you say?

This type service 240/120 ct is usualy found with 3 phase motor equipment and some lights.


Grfetwell nailed it, it would be the electricains fault judging from your post.


Dnk..........

If you search this website's database you can find a confessional of the items we have fried connecting to the high leg in our learning experience. The decent ones among us accepted responsibility for it and replaced the items without alibi.

Dave

In this area, the delta/ high leg set-up is almost unknown; even most sparkies have never seen one. I even got to fix a mess that was set up just as you described.

There really is no "code" as to wire markings and voltages- with the one exception that you note- the high leg ought to be orange. I don't know how old this code requirement is- I certainly have never seen it done! In the delta I recently encountered, the wires were marked blabk, red, blue, with blue on the outside, and the high leg as well.

I can't understand his claim that the "meter is bad" or that he "put in a 100 amp meter, and needs a 200 amp one". As far as I know, the usual utility meter is easily capable of handling over 300 amps. Nor do I think one would be damaged by connecting the high leg to the wrong lug.

And he wants how much to replace the wires? Why?

From your post, this guy seems to have minimal competence- he got in over his head- and questionable ethics. I wouldn't let him in your shop again. Period. Get someone else out there, and get their opinion.

As for the damaged stuff- he breaks it, he buys it. Sure, things happen- that's why we have 'profit margins.' (I am assuming you hired a real contractor, and not some "aw shucks" type handyman).

I have found the 'high leg' in every position possible. This is why one of the first things I do is check my voltage from line to ground. I have seen many guys check line-to-line, and that method will not identify a high leg. Incidentally, the 'high leg' voltage was probably a lot closer to 208 than 240 (just a detail).

A more serious problem should appear in the 'fine print' on the lable of the panel. Odds are, the panel is not listed to be an "appliance panel" for a delta service, and will specifically say so.
This is an attempt by the panel maker to have the electrician set up an additional panel for 120 v circuits. (An 'appliance panel' is one with line-to-neutral circuits). By having all 120 circuits go to a panel that does not have a 'high leg' in it, the fried stuff is much likely to occur.

If you have an inspector, ask him. Who ever 'certified' this guy as an electrician also needs to hear your story. He sounds just a little too marginal.

From my experience you usually see open delta
in an area where most of the customers are single phase, like a small strip mall.
I have set up a few computer rooms with this system in Naples Fla.
The biggest problem we had there was the single phase equipment in the computer room. You usually don't bring a neutral to a computer room panel so the electricians didn't pay much attention to which phase was which.
We ended up swapping some stuff around to get the phases balanced. You really can't put much single phase load on the wild leg, line to line without it drifting since it is only anchored in one direction.
The rest of the building had single phase panels for the normal loads

I see a lot of these, and marked different, and in different locations all of the time.

Many different names for it... Bastard Leg, Red Leg, High Leg, Hi-C, on and on....

Located on "B", and occasionaly "C".

Marked Red, Blue, Orange(NEC), and Purple(Local Code).

Anyway, if doing a service change like this it is the Electricians repsonability to maintain Phase, and Rotation even if a High leg or not. And although I have made the same mistake most others of us have, putting things that don't belong on this leg on it. It would be my responcability, cause I ought to know better, and have checked voltage with any service or panel first. Especially 3 phase, too many variables in voltage and system to just do it blind. (Open delta, corner grounded, Center-tapped/High leg, and wye's...) See this thread: https://www.electrical-contractor.net/ubb/Forum15/HTML/000054.html


Anyway, I screw it up, it's my fault, I fix it. This guy should be reminded of this.... Things didn't catch fire/explode before he got there! And, if he was putting in a 200A MCOP, on a meter section or SEC's rated below that, the work he did was a code violation, and should not have done it. He essentialy bid a violation... Making his work useless to the customer, some will dis-agree, but see this as his problem too. Some of us have probhably done this too, and I think many would cut a deal for that work, not free, but reduced.

I'll go further that that- You can't put anything single phase on the high leg two pole or single pole. Check out 240.85 and then you'll see that UL doesn't List a 2 pole breaker for that panel that has a straight 240v. rating. The slash rated breaker for that panel prevents you from using the high leg for single phase loads. (assuming he's using the right breakers for the panel)

George,
You are correct that the standard 2 pole breaker is not listed for connection to the high leg. However, UL does list 2 pole breakers that are not slash rated, for example Square D's QO215H.

I totally agree with you on the bad apple part.This guy should just take his lumps ,as in learning on the job and paying for his own mistakes!
And yes ...the orange color on the stinger leg does kinda get confusing with the 277/480 recommended color code;in my opinion it would be wise to come up with a unique color scheme for these distinct systems.Maybe this is good for a recommendation to the code making panels?

JBD- Your no doubt right about the square D breaker - I've not been exposed to that breaker. You can bet our butcher talked about in this thread isn't using the right breaker. Thanks for the tip on the breaker.

Thanks JBD. I went to their website and these QO-H 2 pole breakers are available in 15-100 amp. I had previously thought that the high leg could only be used on three-phase loads.

Dave

Two things:

1. Thats the nice thing about this forum, with all the banter that goes on there is always some very important information that comes along.

2. Good Contractor friend of mine will never install any 1Ø loads out of a 3Ø panel. He's probably making a good decision.

George, the problem in the <old> computer business was the single phase load might be behind a 3 phase plug. Some of our "3 phase" stuff was really an assortment of single phase power supplies and a few 3p motors. They also spec'ed line to line plugs on 3 phase panels as a normal course since we tried to never have any L/N loads in the computer room.
Even the small controllers and console terminals were 208/240.
In our delta vee computer rooms we had to monitor this closely.
Now that a "computer" is just a rack of PC boards I imagine that has all changed.

I have run across this on several occassions here in the old parts of town , small shopping centers, older restaurants, and large older houses. It was explained to me by some of the inspectors that this was due to the fact that when air conditioning was first invented that it required 3 phase 240volt power. Don't know if that is a fact as I never really researched it.
But I have had to follow behind a lot of electricians who didn't know and burned up a lot of appliances.
Just as a rule of thumb I always check the voltage on a circuit even when I think I know what it should be. This was beat into me by a former boss who didn't like buying equipment due to improper wiring.
Dave is right the good electrician will always admit his mistakes and sometimes as painful as they can be they are our best teachers.

thanks guys for all your help.
it is nice to have a network like this that you can post things and get GREAT help and information from.

h20

Bogger, I have seen in some older (~1950's) houses with central A/C where a single #10 (I believe) was run parallel to the usual three-conductor drop, ran through the meter, and led to a disconnect that fed just the A/C unit.