please explain this ????

[yahoo]

a friend was doing a locate today on a phone ped with a cable in and cable out and doing this quickly he hooked up to the ground without unbonding. cable located going one way but not the other.. he then hooked up to a pair to try to locate the same bad cable but to no avail. he then called another person to ask for help and he told the locater to just ring clamp the other cable and now it locates!!! so why ....hooked to a pair (or the ground) would the cable not locate ??????? please explain this answer ???

[6feetunder]

Well I don't have an answer but had a simlilar situation happen. I had the same thing where I could locate one direction but not the direction I needed, so I went to the next ped down and tried to bring it back which didn't work either. I tried hot pairing and direct connecting to the sheath and none would work. I decided to ring clamp and it located out just fine. I went to the other end out of curiousity and did it did the same when ring clamped. I never tried to seek out an answer as to why but I would also like to know.

[RD_Wrangler]

I have a possible explanation...

If you were dc-pairing against the flow of the communication signal (?), then that may explain why clamping worked and not pairing.

Connecting to a single pair just wouldn't generate enough of a field to detect when working against electron flow of the cable, and depending on how the hot-pair was dc'd most of the signal simply flowed down the other cable, as that was the direction of signal for the pair circuit.

When you clamped the cable you energised every pair in the cable, which would provide enough EMF for your reciever to detect, even against cable signal flow. Your clamp actually generates a passive signal that is then transfered to the target line through positive/negative electron transfer. When you clamped, you probably boosted frequency? Higher frequency + energizing more copper in the line through clamping = detectable field against flow.

The answer to the question as to why the dc-ing to the sheath/bond or to the ground for that cable didn't work, might be a break in the sheath (common problem) between peds. Broken sheath = break in connection = loss of circuit. I'd be willing to bet a contractor in the past exposed the cable, smashed it, rolled over it, etc...causing damage to the sheath but not the pairs/insulator so it never got caught.

Again, just speculation based on similar circumstance.

[beyond help]

RD's correct. Also. if the bond strap is not correctly attached (especially if not unbonded in the ped), it will not tone it either.

[paintitout]

Unbond the cable and if it still won't locate and you can to it put your lead directly on the cable where the sheath is showing at the bond clamp. See if that will work. Have had luck doing that, clamping it is still a good alternative.

[Goldenboy]

Like was said earlier. When hot-pairing you're signal will only go toward the C.O. As far as hooking to the bond strap without unbonding this could just be because at the other end it wasn't bonded. Easiest was to fix this is to take the two seconds it takes to unbond the cables. Hooking to bond straps can be scary. I've seen alot of times where you get a false tone because of bleed off because of other common grounded utilities. Ring clamping cables in peds does work great but I wouldn't suggest it for the faint of heart.

[Dave72]

Sometimes bond clamps will get corroded at the sheath to bond area. Sometimes a nearby lightning hit will nearly burn it off under there, and sometimes just the action of the original 'bonder' will have broken or nearly broken off the sheath metal by bending it too much while installing the clamp.
You need a full loop of circuit to locate. The signal goes down the line, comes back thru earth (or other utils/etc) and back to your box.
Direct connection on a lifted cable is best. If you get no current flow then either end bond is not connected to this 'loop', or is broken in the middle somewhere.
Ring clamp works the same way, but you just dont need to isolate or connect. The a/c in the ring creates a field in the middle of the ring.. this is induced into the cable. The cable now has the a/c signal and it develops its own field , which you can follow with a detector. You still need a 'loop' for this signal, from one face of the ring clamp to the other.
I would think, for a poor situation, where you have to crank the power and up the freq, that either the direct or the loop would suffer the same problems.. the direct tends to put more power to the sheath in either case. I like direct on the RD, cause you can watch for your ohm level.. if its overrange, then kick the power up.. maybe there will be just enough to jump the gap (mind you that gap jumped might be to another util/etc.. lol)

[yahoo]

[Utilitrack]

No far end ground... trying grounding out your target cable in the next ped downstream.

[walktheditches]

Everyone's pretty much hit the nail on the head for possible answers on this one. Another thing that could have happened, which I have experienced is the cable could have been damaged before and when the tech repaired it they didn't get the bonds secured to both ends of the repaired area or just didn't bother including one. This could cause the issue also. I have seen techs working on cut cables and being in a rush for whatever reason forget to cut and add posts to the sheath area and put a bond strap on before they start their wrapping and have had to remind them. But always un-bond before locating and don't forget to hook the bonds back-up before leaving or that will cause you issues later either on a locate or a phone company rep doing QC.

[yahoo]

thanks everyone for your input!!!!! seen alot of valuable input from you guys!!!

[USIC1]

One more thought, if you have a set of jumper cables and can get your company vehicle close enough to the ground of the target, put 1 jumper clamp on the negative and another to the ground of the target...

Then do the fundamental conductive part of the locate... Make sure your alligator clips are insulated... Rev the engine a few times to get a good flow of electrons into the targets ground...If you can get enough charge flowing it may jump the poor bond somewhere down the line...It could be considered direct amplification of the frequency your inducing...

Let me know how it turns out...

I have a hyothesis about it...

wheres the smiley of rubbing the hands together like a mad scientist???

[Linden Riddle]

The field produced by DC current cannot be detected by a coiled receiver antenna. So the truck battery makes no difference. Neither does the DC current on the the phone cable.

You can send transmitter energy in both directions irregardless of grounding if you utilize a higher frequency. True for hooking onto pair wires, as well.

In the original scenario, perhaps the direct connect was with a low frequency and the coupler was used with a higher transmitter freq (RD Wrangler).

Grounding dictates transmitter current flow. With a direct connect, there is only a single remote ground. With the coupler (or dropping the box for that matter), there are two remote grounds. That's why different things may occur when comparing direct connect to induction.

The transmitter's signal follows the path of least resistance.Transmitter power doesn't have much to do the path of least resistance when compared to the differences between transmitter frequencies or to the differences between direct connect and induction.

Only other thing to consider: you can experience signal cancellation when energizing a pair wire situated inside a well grounded sheath. Doesn't always happen but it can. It'll look like you don't have a locate.

[USIC1]

Okay I m tired of playing with this...

Just radio sweep the bad cable some distance from the ped and drop the box of a high frequency locator and follow the damn thing back the ped...

Cut and dry...

Hard work or hardly working
Time wasted or quick an easy money

What scenario should we strive for???


GEEZ!!!!

[RD_Wrangler]

Just to clarify. In my original post, the use of "dc" was short hand for direct connect.

EG : dc-ing to the sheath = direct connect to the sheath.

Just ignore the idjit and his dementing ramblings about car batteries.