In response to MxSlick's troubleshooting post, I have one that's pretty good too:
The background on this one is at the Building my girlfriend at that time lives in..
The one Superintendant called the electric company I work for complaining there is a " problem with the power to the stove".. (he actually narrowed it down by rolling in another stove and trying that!!)
But anyway, upon our arrival, we shoved our tester in the stove outlet and saw we were getting 120V from each hot slot to neutral and ground but 0V between the hot slots... We also noticed that ALL the plugs and switches in the apartment have been changed, including the split receptacle in the kitchen..
ALL of the lights and outlets in the unit functioned normally.. All showed 120V... At the split in the kitchen, each 1/2 of the receptacle showed 120V but when you went across the "hot" slots you read 0V ( where you should see 240)...

Down in the electrical room at the unit's disco we found on the LINE side 120 to ground on each leg, 240 across the legs.. Normal..... On the LOAD side we found the same 120 to ground, BUT the same 0V from leg to leg...
Across fuse "A" read 0V, but across fuse B read 240V...


Now, it would appear there is an open fuse, which indeed there was BUT there is that weird 120V backfeed and the entire apartment works as if nothing is wrong
( with the exception of the stove)....

The service to this apartment unit originates from a 600A 120 / 240V single phase service.. It comes off the splitter and goes to a 60 A FUSED disconnect, ( fused with --very old-- regular one time fuses) and then from there it goes to the unit where a 12 circuit breaker panel was retrofitted in..

Now:
Can or does anyone want to give a shot at what the problem in this apartment unit is, or where it is, or the sequence of events that happened to cause this condition to happen????

I will try and check in later or tomorrow (tuesday) evening should anyone have the answer ,has questions or wants to know what happened!!!!!

A.D

Someone changed the split recep and forgot to cut the tab?

Blew the fuse, electrician or homeowner couldn't figure out what went wrong, and put everything on one phase and went home?


Dnk...

Bad meter lug.

No, we all know it wasn't the meter lug, but standard operating procedure is to blame the POCO first.

Quote:
"Someone changed the split recep and forgot to cut the tab?"

That sounds right. Replaced the receptacle, it blew the fuse, but nobody knew 'cause the 120 still worked everywhere else through the tab.

...either that, or the darn POCO......

Dnkldorf / WFO !!!!
YOU BOTH WIN!
Ya it was the split and it was backfeeding through the "tab"...
Funny thing is though, the same super kept doing the SAME thing and calling us.. He could never figure out why when we arrived we went right for the split receptacle when there was a "problem with the stove"

What did I win, an all expense paid trip to my living room?

Hot diggity........

Dnk...

The chance to " Play again" sometime!!!!!
A.D

I cheated. I read Dnkldorf's post. I knew it was a backfeed but didn't catch the receptacle until he did.

So in all fairness, he can have my half of the trip to his living room.

....no, really! I don't deserve it!

I was thinking about it simply being the locked rotor from the A/C plus the water heater element.

I had a similar problem on my first call at IBM (1966), on a 3 phase, multi motor, machine with multiple motors ... missing a phase. I didn't notice the bigger motors running slow but the tiny one was running something with a timing disk on it that had an error so I started there, scoping timing pulses.
I didn't think I was missing a phase. I was getting something on all of them to ground. I saw still scratching my head or perhaps a more southerly region, when another guy came in and said "those motors don't sound right, you lost a phase kid".

AD, the unbroken tab may have blown the fuse, but most phase-to-phase loads will feed 120 to the load side of the open fuse in the same manner, as mentioned by G-fret.