Electrical problems at home related to RPC

On Sun, 15 Jan 2006 23:26:14 -0600, B.B.


Too late:)
I already tightened the set screws... Just held the allen wrench with linesman pliers and wore rubber soled shoes. :)
i
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Ah, so I read. Oh well, at least you used pliers. (:
--
B.B. --I am not a goat! thegoat4 at airmail dot net

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On Fri, 13 Jan 2006 15:01:22 -0600, Jon Elson

Use a 3/8 inch drive hex wrench/socket (a socket with a short hex wrench in it), suitable extension and a ratchet. Tape up the extension if you so wish. Find a nice piece of dry wood, plywood, 2x8, 2x10... whatever you fill comfortable with not falling/stepping off from and stand on that. Look over exactly where the hex lug is and what could possibly get in the way when you turn/wrench on it. Then carefully crank them down.
Don't get too carried away with this. That is more than enough wrench. If you pop/split one (been there, done that) it is a pain-in-the-xxx to fix and it HAS to be fixed. Especially on a hot panel in current use for important things, like keeping beer in your fridge cold.
If you feel really uncomfortable doing this, find an electrician that works on commercial/industrial stuff. They will torque them down with a big grin on their face and maybe help you drain some of that cold beverage in the fridge afterwards ;-) There is even a good chance they won't bother with the wood either. Some of my old work boots were okay, some gave you a small tingle and some would knock you on your butt if you weren't standing on something insulated <grin>.
I really think you need a small pony motor to bring the big 10hp idler up to speed first though... or at least partially spin it up <shrug>.
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Leon Fisk
Grand Rapids MI/Zone 5b
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Jon Elson wrote:

A good molded handle T type Allen wrench would probably be safest. The molding would likely be enough insulation, but a wrap of electrical tape wouldn't hurt. You're only insulating for 120V so it's not that bad. The bad part is mostly the what if in the event you somehow create a short.

I've seen worse than that. The one that amazed me was the line that ran from a manhole that had a 4' high plywood wall around it, through a 6' length of that yellow jacked cable protector on the ground, up a tree and then tree to tree at about 8' high alongside a sidewalk for a good two blocks before disappearing down an alley. This was not a simple 240V feed to a nearby building, it was a primary feed, probably 13.2kV and was well within reach of anyone on the sidewalk.
Pete C.
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On Fri, 13 Jan 2006 15:01:22 -0600, with neither quill nor qualm, Jon

Wuss. Get a long-reach 1/4" (or 3/8") drive allen socket, shrinkwrap both the allen and the socket, and wear gloves. Not a problem, guys. First in google: http://search.ebay.com/allen-socket
If you're still afraid, triple-shrink the allen portion. Just remember to leave 3/16" bare at the working end, eh?
--- Chaos, panic, and disorder--my work here is done. http://diversify.com Comprehensive Website Development
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Jon Elson wrote:

I'd avoid using an L shaped allen wrench. I used a straight ball driver with a large insulated handle on it.
Steve
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Steve Smith wrote:

I *HATE* and *DETEST* working live.
I cannot reccomend that you do so, but hypothetically, - if you were to consider doing it yourself - further to the other peoples comments, take off metal rings, watch straps, neck chains etc. Dont wear *any* synthetic fibre clothes that can melt or burn etc. Outer clothing should be heavy wool or leather (cotton burns too easily) and cover as much of your skin as possible. Wear goggles or protective glasses, vaporised copper goes a surprising distance and wont do your eyes any favors. Gumboots would be a good idea in addition to the DRY insulator to stand on. To reduce the risk of taking a shock across the heart, keep one hand, preferably your left in your pocket at all times. Have a trained first aider standing by with a phone, a dry powder fire extinguisher, a blanket to put you out if you are the fire and a dry broomstick to seperate you from the line just in case. Remember, if you are working live, any earthed surface or object is a hazard. You cant shield the terminals you need to tighten but you may be able to shield most of the box, conduits etc. so there is NO WAY you can come into contact. Remove or protect any sharp objects etc. you could get thrown against. Make *SURE* you have good enough lighting, and that it is NOT dependent on the circuit you are working on. Dont have a hangover, coffee, too much tea, be tired or just awakened or unwell - you need a steady hand and a clear head.
Final advice, *HIRE IT DONE*
--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
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Ian Malcolm wrote:

I think your going a bit overboard there, those precautions are a bit more suitable for primary work or at lease 480V switch gear. Remember that we are talking about 120V here, it doesn't take that much to insulate against 120V, heck where you are you use 240V as your normal household voltage. The threat in what's being proposed comes from the high currents available, not from the voltage.
Bolt-on type circuit breakers are routinely connected live and not much of a problem. The key thing is that there is generally a main breaker upstream to shut things down in the event of a short. Working live before the main breaker if there is a short things will stay lit up until something melts open, doing a lot more damage.
Pete C.
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Pete C. wrote:

Iggy is considering working on the feed to his panel. We presume there is a supply company fuse somewhere upstream but with Iggy, who can tell?
With the exceptions of the gumboots, making sure you are clear of sharp/spikey objects and keeping one hand in your pocket, everything else is equally applicable even when working on 48 Volt BATTERY supplies. With that in mind, does the fact that he's not likely to get himself accross more than 120 V (though there is 240 V in there phase to phase) make a lot of difference compared to 240 V panels over here. As I said, vaporised copper & steel is not your friend. If one of the screws shears and the driver slips, what happens next?
Nearly everyone was concentrating on insulating the tool, not on protecting Iggy. IMHO he needs to do *BOTH* so that if something goes wrong, he's got a chance to come back and tell us how he *nearly* had a bad accident, rather than the alternative.
--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
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Ian Malcolm wrote:

The fuse will be on the primary side of the distribution transformer and is unlikely to blow if someone shorts one phase in their panel.

The construction details of all the code approved distribution panels in the US take care of pretty much all the clearance issues.

Not a lot, only a small difference in the insulation necessary and any decent electrical tape will be good for either.

Can't happen in the US panelboards (from the last few decades at least), the top of the Allen setscrew is generally close to flush with the top of the connector block. It's also a decent size Allen setscrew, like 5/16" or possibly 3/8" so it's unlikely to strip internally either.

We must presume that he has enough sense to not try this while standing barefoot in a puddle, after all he hasn't killed himself with his RPC or welder yet.
Pete C.

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Thanks, Pete, Ian, and all.
I just retightened these screws, with an L shaped Allen wrench. I did it by wearing dry leather gloves, I held the end of the allen wrench using linesman pliers that have insulation on them. At no time I held the wrench by my hands, only with pliers. The house did not explode and the screws did in fact take some tightening, without even a huge effort.
I will see if this helps. My wife and baby are sleeping in the affected room, so, I will try it later.
My own thinking right now is that nothing was wrong with these screws's connection, even though they were not super tight. What was wrong is that the UPS that the TVs and other electronics are on, has an old battery that needs replacing. When the power dips a little, the UPS is too quick to change to a battery, which did not work due to poor condition of the battery. The solution is replacing the battery (and the UPS). I am going to put that equipment, which is kind of expensive, on an APC 2200 UPS instead of the current APC 1400 UPS. I recently bought several 2200's from the military.
i
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Pete C. wrote:

I'd expect the screwdriver, wrench or whatever to loose a fair bit off the end then. Over here, we tend to have a *LOT* of households tapped off each phase in turn of a three phase 240 V main. Due to the extremely large current available, the feed to the meter comes through an electricity company owned fuse, (or one per phase). Wireing up to that fuse is NOT MY PROBLEM and after the meter is my responsibility. I can pull that fuse if I need to work on the board, but have to get the company out to check and reseal it on reconnection.

And so it is with modern consumer units (thats what they call the domestic ones with an integrated masin disconnect) over here.

Yes.
Good to know.
I've stripped out some real horrors over here. Pre war as far as I could tell. Mahogony case with a mica window, two brass buss bars with *thumbscrews* !!! and either side more thumbscrews and terminals for the other end of the fuse wires. It had fuses in both live and neutral, (I belive there used to be a DC system that was symmetrical about ground in the area) and it had a couple of its set of little sprung flags left that would pop out into the window when the fuse wire broke to indicate which circuit was blown. The disconnect feeding that was a knife switch which had a metal guard that wasn't grounded. The whole lot was wired with cotton covered wire with totally powdery hard rubber insulation. Not supposed to still be in service, but the previous owner had been there since the place had been built back in the 30's. She used to plug her iron in the kitchen light socket. Between that and a three phase panel and sub panel in our workshop where some idiot had ripped out the conduit which had been the sub panel ground and rewired it without one, and the bare unlabelled buss bars inside, there are plenty of ways to get in trouble over here.
The government has finally brought in a law that all domestic installations must be inspected by an approved contractor (who will normally insist in being paid to do the work as well as to inspect) and changed the wiring colours so as to keep the DIYers honest. Looking at some of the stuff I've seen, I guess its probably for the best, but those of us DIYers who were working to code are slightly pissed off because previously, unless you were very lucky, you'd wind up having to sort stuff out that wasn't up to spec if you had occasion to open up any part of an installation that had passed a full inspection, or even find remedial work you had paied for 10 years ago hadn't been completed.

Well he's gone and done it without running into any trouble, thankfully.
Its been an interesting discussion. Thank you.
--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- &
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On Sun, 15 Jan 2006 03:33:57 +0000, Ian Malcolm

Thanks guys. I retightened the screws (without trying to apply too much force). To my slight surprise and delight, the RPC does not seem to cause the UPS supplying the TV to turn off anymore. My wife says that lights darken a lot less now. And that is without any extra capacitors etc. These turnoffs were a little intermittent, so I am reluctant to announce complete victory.
I am quite happy and thankful to all for your suggestions.
Like I said earlier, I held the L shaped allen wrench with linesman pliers with insulated handles, to avoid being electrocuted.
i
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On Sun, 15 Jan 2006 03:53:24 GMT, Ignoramus22325
<snip>

Well, you're not dead and it worked, but if there's a next time, consider what might have happened if the pliers had slipped on the allen wrench. I think the various ideas of taping the wrench or using a plastic T handled wrench, all with dry leather gloves, were less risky.
Glad you found the cause and didn't get hurt.
Pete Keillor
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wrote:

Nothing major would happen, the allen wrench would either stay in the setscrew, or it would fall to the floor.

Thanks Pete, could not do it without your and others' help.
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The allen wrench doen't always stay in the screw or fall on the floor. It can and often does weld itself inside the box, possibly along with the pliers. It only has to happen to you once before your willing to spend 5 minutes and 25 cents worth of tape to insulate the allen wrench.
Even if you aren't electrocuted when you weld a wrench in a box you will usually end up blind for 10 or 15 minutes.
Cheers,
Kelley
On Sun, 15 Jan 2006 16:50:52 GMT, Ignoramus26433

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Ignoramus22325 wrote:

It was probably a function of coinciding with other large loads like an electric stove or clothes dryer. I guess you don't have voltage drop readings from before and after, but since the UPS should be trying to switch at a specific voltage you may have reduced the drop enough to miss that threshold. Of course the regulator down the street somewhere could have been adjusted or drifted slightly higher as well.
Pete C.
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You could have a great point about electric stove, which was on at some points. Like I said, it was intermittent, so I do not even know if I fully cured the problem. I tried the RPC a few times this morning, no problems so far.
i
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Ian Malcolm wrote:

Here the first protection after the drop is the main breaker in the house panel. You're responsible for the meter socket on. There are code limits on the distance the unprotected feeder can travel inside the house before reaching the main breaker and if the panel and service entrance need to be further apart you have to provide a main breaker at the meter socket.
The utility puts their little seal on the meter socket here too, but they rarely seem to care much about it unless they have reason to suspect you are stealing power. I had to replace my meter socket on short notice when it failed some years back so I didn't contact the utility. It was years later when they changed the meter to the new remote read ones that they actually put a new seal on it.

Yep, the real old stuff can be pretty scary although people are far too paranoid about old knob and tube wiring. I'm still not sure the "modern" stuff is all that good in some areas though. I've seen some pictures of some apparently much newer service equipment that appeared to be quite new DIN mount breakers and whatnot mounted on a section of DIN rail. All fin to that point, but this DIN rail was mounted in an under stair closed to the back of a stair riser with no enclosure around it. I hope this was just a one off hack job.

Here the old stuff is "grandfathered" and allowed, but if you do any significant electrical work that requires a permit you will generally be required to bring the old stuff up to code as well. Here the homeowner can generally do their own electrical work, but they have to get a permit, follow codes and have it inspected just like any electrical contractor would. Generally seems to be the best way to do it as I will not permit anyone to force me to pay someone to do what I can do at least as well myself.

It's interesting how things vary between countries too.
Pete C.
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wrote:

Jim and I appear to be the only logical ones here <G>..and forego all the crap needed to self start large RPCs, by using a pony motor.
Thats 2 things we agree on. When the third pops up..the earth will experience a pole shift. <G>
Gunner
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