WANTED – a clever way to find where…
WANTED – a clever way to find where…
WANTED – a clever way to find where, in 181 garages, 67 wall packs, 65 pole lights, thousands of feet of underground conduit, kluge repairs, PVC splices, forty years of electrical history and assorted this and that, they done tied them white wires to them green wires.
Surely, you say, they done tied them together way up stream, at the service equipment, as per 250…
Nope.
In point of fact, while they are out in the runs, not a single little green wire appears out of any conduit into any panel, sub panel or sub-sub panel that we have found.
The subs are grounded back upstream via the collection of metal conduit. Gives you a warm, fuzzy feeling of security.
The ToolBear
“Never met a man who couldn’t teach me something.” Anon.
Replies
TB,
By the time you get done "Saving" that old wiring, the labor alone is gonna cost as much as just doing a complete new installation.
Since I've been following you Star Trek type mission from the beginning, I've put some random time into thinking about how I would do it to be most cost effective. You get to try and get the bosses to sign off on it.
First, disconnect every possible connection.
Then megohm every conductor at every location to every other conductor there.
Finally, apply a signal to all (one at a time) good conductors at every location and search all other locations for that signal. While the signal is present use a tracer/line-locator to physically map out the conductor paths. You want a line locator that only senses the signal and not just the presence of any old wire. I dunno what you're gonna do about the wires being in conduit. You may just have to map the conduit.
IMO, you really need to have a good diagram/map of what is existing, if you're going to try and salvage it.
SamT
Guys that don't do things correctly the first time.....then argue that they did nothing wrong.....if made to agree to fix the problem, rarely put the time and effort into truely doing it properly. they'll just look for the quickest fix to appease you and get their money. JDRHI 84310.51
I agree. According to his profile he should be in So Cal. Certainly warming than the near zero's we are seeing.I think that 2-4 weeks of some consulting time we could get it mapped out for him..
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
2-4 weeks?
1 day touchy-feely. 1 day to develop a plan of attack. 1 or 2 days to develop paperwork, maps, blank wire lists, etc.
Let's see, 313 stations. . . average 16 the first 2 days, then 24/day, that'ld be 15 days. I'm willing to work 7 tens if the pay is right. You? That would cut the calendar time in half.
Ahyep. about 4 weeks. Do ya 'member when his first post was? 'Bout 6 weeks ago, wasn't it?SamT
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein] Tks, BossHogg.
I agree. According to his profile he should be in So Cal.
It's spring here now. Things are in bloom. I am sneezing.
Where are you freezing at?The ToolBear
"Never met a man who couldn't teach me something." Anon.
" I agree. According to his profile he should be in So Cal.Certainly warming than the near zero's we are seeing."Tool Bear is working in Newport Beach, Orange County CA. Forecast is for temps approaching 80F tomorrow. Better not come out here, you guys probably couldn't stand the shock of sudden temp change. :)
BruceT
You outed me, you rascal.
It was hot out there today.
We don't want to make them envious of our laid-back SoCal life style. They will want to immigrate. My work costume is shorts, sneakers, T and knee pads. I should not mention this.
Then I come home and see some new story about it being cold in Chicago. Duh? That's news? I used to live there until I could escape. You freeze your buns in winter. Nice breeze down Michigan Ave. Windchill somewhere way south of 0.
The ToolBear
"Never met a man who couldn't teach me something." Anon.
My work costume is shorts, sneakers, T and knee pads. I should not mention this
Gee, thanks for telling us that.
I can hear the wind howl and the temp says 4degrees with no break in sight.
be and even the thought of it hurts
I just heard about a town in MN where they had to close down the outdoor ice rink due to cold weather...-42 degrees, not counting wind chill!BruceT
just heard about a town in MN where they had to close down the outdoor ice rink due to cold weather...-42 degrees, not counting wind chill!
I camped at Devil's Lake, WN, one December. We pitched the tents in the large picnic pavillion. Had a good fire in the fireplace. One foot from the fire, my water bottle was frozen. That's cold. The ToolBear
"Never met a man who couldn't teach me something." Anon.
Then I come home and see some new story about it being cold in Chicago. Duh? That's news? I used to live there until I could escape. You freeze your buns in winter. Nice breeze down Michigan Ave. Windchill somewhere way south of 0.
HAH!
I was born and raised in the Imperial Valley, south of Palm Springs, I moved to Missour-ah.SamT
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein] Tks, BossHogg.
HAH!
I was born and raised in the Imperial Valley, south of Palm Springs, I moved to Missour-ah.
Ah, yes, the San Andreas fault dips down and kinda, sorta vanishes there. Of course, there is the Sea of Cortez to the south.
Then you know the meaning of warm. Certainly in summer. Missour-ah must seem cold in comparison.The ToolBear
"Never met a man who couldn't teach me something." Anon.
Missour-ah must seem cold in comparison.
Hah!
Florida would seem cold in comparison.SamT
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein] Tks, BossHogg.
Star Trek - as in .. boldly go... ? Grope is more like it.
IMO, you really need to have a good diagram/map of what is existing, if you're going to try and salvage it.
I'd love a conduit map. I'd love it if they would just fill in the panel circuit list with a few hints when they install stuff. The only entries are mine, and I didn't lay the stuff. I just finished a pole light -wall pack map and will probably have to circuit-map which breaker controls what.
Probably have to break open the ____ (insert method here, they did them all) that runs in and out of the garages and see what is there.
I am logging the number of conduits, direction of line vs load, the number, AWG, type and color of incoming, outgoing wires at each pole, the voltages across all the combinations, etc. I will be abe to reconstruct the pole light system from this. Electrical archaeology is what it is.
On the other hand, the protocols I get to develop will make future area lighting projects so much smoother. Step one - map the light locations. Assign them numbers - of the nearest front door. Etc.
The ToolBear
"Never met a man who couldn't teach me something." Anon.
Toolbear -
I don't know how things are in So. CA, but conduit maps around here are pretty much useful only for scrap paper. Furthermore, what odds will you give that even if you had maps you're dealing with a few buried splices. - lol
"Electrical archaeology "
Sounds like a new career opportunity - add it to the cirruculum at your local university!
I'm afraid that you're going to have to bite the bullet soon and go to the owner with a complete rebuild/rewire on this one.
Between the rotten conduit and the wiring not meeting code, I just don't see an easy fix.
Good luck
Between the rotten conduit and the wiring not meeting code, I just don't see an easy fix.
Actually, the happy note is that the conduit I have encountered is in good condition. Had projects where it's all rust and memories. There we dug and relaid the circuits.
I dream of finding the boxes where they married the green and the white. This is like an Easter Egg Hunt.The ToolBear
"Never met a man who couldn't teach me something." Anon.
Sorry; thought the conduit was no good. Google: thhn tdrOne of the top results is: JTE ShortStop ManualTime Domain Reflectomers (TDR) will measure lengths to shorts or opens. The Shortstop looks like an inexpensive example. I've used expensive ones that can even find splices; probably more than you'll want.
WANTED - a clever way to find where, in 181 garages, 67 wall packs, 65 pole lights, thousands of feet of underground conduit, kluge repairs, PVC splices, forty years of electrical history and assorted this and that, they done tied them white wires to them green wires.
There is test equipment that will do just that. It's called a "time delay reflectometer". If you call any electronic test equipment rental place (electrorent, hp, etc) they should be able to provide one. Expect to pay $200 a month or so to rent short term.
The TDR sends a pulse down the line and measures the reflections. It reports the distance to ANY connections on the lines. More sophisticated instruments can identify the type of connection ( i.e. short, soldered connection, mechanical connection, high resistance connection, etc). You want a 2 channel unit, which will test two wires and find shorts between them. The information the instrument will report will be a distance to the connection.
So this instrument will tell you which wires are shorted and where the connection is. You may still need to do a little "digging" but it sounds like just knowing which wires are connected would be a big start.
There is test equipment that will do just that. It's called a "time delay reflectometer". If you call any electronic test equipment rental place (electrorent, hp, etc) they should be able to provide one. Expect to pay $200 a month or so to rent short term.
Thanks for the tip. I go a Googling. The ToolBear
"Never met a man who couldn't teach me something." Anon.
TDR will tell you distances and types of discontinuities, but it won't tell you about direction. It will note a change in direction, like a folded wire, or tight radiused turn, as a discontinuitiy.SamT
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein] Tks, BossHogg.
TDR will tell you distances and types of discontinuities, but it won't tell you about direction. It will note a change in direction, like a folded wire, or tight radiused turn, as a discontinuitiy.
I'm not sure what you mean by "direction"? A TDR should not report a kinked wire as a discontinuity, at least not current equipment.
Modern TDRs are rather sophisticated machines - they use a DSP and proprietary algorithms to detect a large range of conditions on a wire, with uncanny accuracy and perception. A tight radius turn should be reported as a kinked wire, not a discontinuity.
Given the magnitude of his problem, it seems like it might be worth a try. It should at least narrow it down to particular cables and within a few feet (and more likely inches) of the problem(s).
Direction = north, east, south, west.
Discontinuity = any change in impedance.
Impedance can change due to a change in ohmic resistance, a nicked wire, a connection or splice, a sharp bend, a termination, even a new wire joining the bundle or a gap in the conduit.
If I were there (|:>) I would save the TDR for after mapping the system ala 85146.2.
A TDR scope willl no more tell you where to dig then knowing all the dimensions of a house will tell you how to build. . . unless you also have the prints/map.
By the time ToolBear has mapped the system, he will know which few problems must be dug up to repair, then the TDR will be 'priceless.'
I considered mentioning TDR in 85146.2, but thought that mapping was much more helpful at this stage and decided to wait till he was at a point where TDR was the best solution for the problems remaining.SamT
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein] Tks, BossHogg.
Time-domain reflectometer...
Want to be clear - these will work on common plain old electrical wire, not coax, twisted pair, etc.? My googling turns up mentions of LANs and such.
The ToolBear
"Never met a man who couldn't teach me something." Anon.
http://www.flukenetworks.com/FNet/en-us/findit?Document=9820563
Fluke TS90 manual discusses just your situation.
Cost (from google) is $160 low to $239 high. I didn't check beyond that.
Marc
TDRs aren't magic, they have some real limitations. For what they are designed for, nothing else will do: measure the distance to a discontinuity.
They were originally designed to locate discontiuities in closely coupled conductor pairs. Specifically,coax cable.
They will work on any parallel conductor pair, like romex or wire in conduit, as long as the pair is closely coupled, basically, that means as long as the 2 conductors are close together and parallel.
I am an old time user of old time TDR oscilliscope type instruments, which require an experienced operator to interpret the output. These new TDR meters compare to the original like a continuity tester compares to a multifunction volt amp ohm meter.
Using a TDR 'Scope is not like riding a bicycle, so I no longer consider myself "experienced."SamT
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein] Tks, BossHogg.
Sam,
I also used TDR 'scopes "in another life".
For what ToolBear needs, the meter is very likely to work well.
The magic of being able to analyze how well a connector is installed or finding where the radius of the cable bend is too tight using the TDR is great but I rarely needed those capabilities.
>99% of the time, it was how long is the cable?, is it shorted or open?, did the cable get cut?
From what I can tell from my reading, the meter (especially if Fluke manufactures it) is plenty for electrical work.
>Gives you a warm, fuzzy feeling of security.
That ain't security! That's your arm hairs lifting when you get too close to them wires!
Edited 2/8/2007 2:54 am ET by Reyesuela