When you decommission a 2 wire 240 volt circuit that does not use a
240 volt specific outlet you ALWAYS disconnect it at the breaker. That way there is no chance of ambiguity. A good idea on any "dedicated" circuit too. If there is nothing else on the circuit don't just wire-nut it off in the jbox. Either disconnect, or better yet label and lock out the breaker involved.
If you have 2 volts difference with no load, and 18 volts with a load, you DO have a neutral problem - The fact that the high side comes down and the low side goes up with no load proves it HAS to be a neutral problem. There is no other possibility. How long is the feed from the main to the sub? What kind of cable did you use? How deep is it burried? Is it direct burial cable or in a conduit? Is it running under a driveway?
Something is still not adding up. Also, do you have a driven ground??? If not, get one in there and test again.
8 volts difference, NOT 18 volts difference. I am guessing (not going out and measure) that the distance from box to box is approximately 140'. All I can tell you about the cable is that it says "AWG 2 AL TYPE VSE-2 60 MILS XLP INSULATED 500 VOLTS" and that it is black. It is buried approximately 4' deep and is not under a driveway. I do not believe there is a driven ground rod at the shop. I did just happen to put an 8' one in about three weeks ago for a "long wire antenna" for antique radios that I have and it was not fun.
I appreciate the advice but it has been working well for approximately eight years so nothing new is going to happen in the near future. We will be leaving state tomorrow for New Year's Eve parties, returning for a short period and then going to Florida until the beginning of March. During that period noting runs in the shop except the central propane fired hot air heating system.
I am sure you don't care but that is too small for 100a.
You must have some fairly heavy load in there. Yes, move some of the heavier loads to the opposite leg. Try to balance them. If you have a clamp around amp meter, put it on each main wire.
Do you have a green wire coming from the house? If not, you should have a ground rod, and I believe I read that anything over 100' should have one anyhow. When weather allows, I'd put in two ground rods and connect them with #6 bare copper wire.
IGot2P wrote in news:1c56e$5680c962$adba3119$30641 @ALLTEL.NET:
Which only confirms what you were told a week ago by clare, gfretwell, trader, and I'm not sure how many other people: you have a bad neutral connection.
Since you don't seem to understand how this works, or the level of danger involved, I recommend you hire a qualified electrician to find and fix the problem ASAP before your house burns down.
Uncle Monster wrote in news: snipped-for-privacy@googlegroups.com:
No, it probably doesn't. And the problem isn't what's coming from the power company anyway. The problem is that his neutral connection is bad.
Uncle Monster wrote in news: snipped-for-privacy@googlegroups.com:
No, it's not. It's time he calls an electrician to fix his bad neutral connection.
I agree. My point was that on even those old circuits, it was the neutral that was the essential component of supplying 240/120V. And when the neutral is shared, it's the ground that's sharing the neutral, not the other way around. The circuit could work with no ground. It can't work with no neutral.
It would seem to me that any time your decommission any circuit, you would disconnect it at the breaker.
What you're seeing is the symptom of a bad, partially functional neutral. With no load, the voltages measured between either leg and hot will be equal. As soon as you apply an unequal load on the legs, then current flows in the neutral and you see the voltages differ. The larger the load, the greater the difference. Tell us the amps flowing, the voltages you are measuring and we can tell you how large the resistance is that shouldn't be there. If the resistance is large enough and the current high enough, it's going to get hot, very hot. If you have a 5 volt drop and 100A, that's 500W at the point of the bad connection. How lucky do you feel today?
And rebalancing loads is just covering up the problem. It's only effective if the loads on each leg are equal and on at the same time. How are you going to achieve that?
Like others have suggested, probably time to call an electrician.
Particularly with the AL in there. Sounds like aluminum, which needs to be upsized - and at 140 feet also needs to be upsized.
If he has everthing on the one leg the neutral wire is carrying ALL the load. If he splits the load equally the neutral carries no load - so yes, balancing th load may get rid of the voltage inbalance, but he still has a problem. MIGHT just be undersized wire for the load and distance - combined with no ground - but I'm atill thinking neatral problem. (and undersized neutral COULD cause the problem if the load is unballanced)
*Measure* the potential between the neutral in your (workshop) box (or, at any free outlet) and this ground rod taking care NOT to short them in the process.
How do you KNOW that? Do you have a record of these observations/measurements that dates back to that time?? I.e., for all you know, this may be a recent development... or, related to the current loading, etc.
Horses for courses. I tend to not like *leaving* a problem for fear something I've failed to consider will bite me in the *ss while I'm "away" from it!
Enjoy your trip!
The problem with your solution is the voltage at the "main" panel in the house has no problem. He has a problem between the main and the sub. Underszed feed (for the length) and inballanced load could explain it. Otherwize he has a neutral problem.
My saying an undersized fead and inballanced load could cause it would only be because the neutral was overloaded by the inballance. With a properly balanced load the neutral carries NO current.
On Wednesday, December 30, 2015 at 8:04:45 PM UTC-6, snipped-for-privacy@snyder.on.ca wro te:
I think you have a hybrid word "imbalance" and "unbalance"? (or I'm not com petent in Canadienese) (?_?)
Yea, it should have been spelled Imbalance. I used to be a very good speller in my younger days - last one standing in spelling bees, but there are more words now, and I've let my spelling slip - and generally don't use spell-check.
There are a lot less words now if you listen to that garbage Rap Music the kids listen to these days. They can write an entire 5 minute song using only 3 or 4 vulgar words!
On Wednesday, December 30, 2015 at 9:04:45 PM UTC-5, snipped-for-privacy@snyder.on.ca wro te:
power company anyway.
the meter base could be a problem if it's loose. There are all kinds of thi ngs that can cause an imbalance which is why, in another post, I wondered i f the problem had just suddenly appeared after everything had been normal f rom the start. If the OP has inspected the neutral connections everywhere h e can get to and believes it's a bad neutral connection then he should cut the seal off the meter, pull the meter and check the connections there. So if his neutral connections are good all the way through to the meter base, what should he do next if he doesn't have pole climbing gear? Of course he should contact his power company and inform them that he cut the seal off t he meter socket and the reason why. If it's one of the newer remote reading meters, the power company will know anyway but it's best to inform the uti lity. ?.?
Perfectly balanced would be a better term, which of course isn't possible unless all the loads are fixed. In a shop like he has, like almost anywher e else, the loads are never going to be perfectly balanced. The problem isn' t the balancing, the problem is he has a bad neutral connection.
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