question about "double hooking"

**Red105** · July 30th, 2009, 08:36 PM

i few months ago, i was shown a technique by another locator from a different district.

when locating a phone cable, in a situation where we could not get continuity and had tried almost everything, he proposed that we "double hook."

the locator took the black lead from the ground rod and clipped it to the bond strap attached to the other end of the cable in the pedestal... one end had the red lead, the other end the black lead and we had super continuity, where the rycom transmitter almost shorts and shuts itself off.

we located the cable out just fine, but he told me not to tell anyone that HE (specifically) had shown me that technique because he said that it was against company standards for an acceptable hookup.

why did hooking both leads to the two ends of cable give us such great continuity and why would it be an unacceptable setup?

**RD_Wrangler** · July 30th, 2009, 09:36 PM

Need some clarification here...

He connected the ground lead (black) to the bond strap of the same cable as the connection lead (red) was clipped to? Or did he clip it to another cable in the pedestle?

Also, what frequency were you using?

Side note : Continuity would have little to do with the transmitter shorting out. Continuity is simply a term for the condition of a circuit and for us (locators) an indicator of ground path return quality.

**TheCableVine** · July 30th, 2009, 11:17 PM

If I am understanding this correctly, that is one of my favorite techniques.

If I have two cables in a ped, one going east and one going west, I will unbond them and hook red lead to one cable and the ground to the other and then locate away. It works great.

It doesn't work for two cables traveling in the same direction or parallel in any way. I wouldn't recommend it anyway.

The reason I believe it is frowned upon is because you don't really know what is going on at the other end of the cables and you don't know if you have a completely separate ground.

**Red105** · August 1st, 2009, 11:05 AM

yeah, cablevine you understand what i'm talking about... i was curious about how that even works in the first place, to me i just know it works but i'm not sure how. i didn't think that hooking the black lead to another isolated cable would affect the one the red lead is connected to.

on a side note, then what is it when the machine is about to short circuit if not continuity so i'll know what i'm talking about. thanks.

**Dave72** · August 1st, 2009, 11:39 AM

Thats pretty much the same idea as hooking your red lead up to the target cable, and extending your black out (extend it even) way off to the side (away from the ped). This separates the supply and return paths enough so that you can pick up the field with the detector. By clipping the black to the other cable, you were just extending the return connection.

In some situations, if you just clip the red to a cable, and the black to the ped ground.. you can get the supply and return flow running basically parallel (picture the one path inside the cable, and the other path just outside of the cable sheath).

**underground quester** · August 1st, 2009, 08:55 PM

Originally Posted by TheCableVine

If I am understanding this correctly, that is one of my favorite techniques.

If I have two cables in a ped, one going east and one going west, I will unbond them and hook red lead to one cable and the ground to the other and then locate away. It works great.

It doesn't work for two cables traveling in the same direction or parallel in any way. I wouldn't recommend it anyway.

The reason I believe it is frowned upon is because you don't really know what is going on at the other end of the cables and you don't know if you have a completely separate ground.

Just had a great thought, for those of us who locate in the great white north, winter grounding SUCKS at times. This gives me another option if I can determine which lines are going opposite directions. Most often, but not always, the lines are marked.

ThanX for the clarification everyone, I was struggling to understand what Red105 was talking about.

**yahoo** · August 1st, 2009, 09:48 PM

this is a great way to get a very good ground..........the exception that has been brought out is if the cables happen to parrelel each other....i love learning more about this job

**Wingfoot** · August 1st, 2009, 11:01 PM

Originally Posted by TheCableVine

Originally Posted by Red105

I was shown a technique by another locator - "double hook." He told me not to tell anyone that technique because he said that it was against company standards for an acceptable hookup.

Why did hooking both leads to the two ends of cable give us such great continuity and why would it be an unacceptable setup?

This is one of my favorite techniques.

It doesn't work for two cables traveling in the same direction or parallel in any way. I wouldn't recommend it anyway.

The reason I believe it is frowned upon is because you don't really know what is going on at the other end of the cables and you don't know if you have a completely separate ground.

Red - What your buddy is telling you about "double hooking," you should never admit to using it. Not ever....... Especially at damage time! Capisce?

-----------------------------------------------------

**phoenix827** · August 2nd, 2009, 07:17 AM

ok, explain the negs a bit more for me would you?

The reason I believe it is frowned upon is because you don't really know what is going on at the other end of the cables and you don't know if you have a completely separate ground.

From what I have seen you never know "for sure" unless you only have one util in the ground, even then you could be jumping onto ground water and following that. What else could be

going on at the other end of the cables

? (beside jumping to another line)

**GPGrasshopper** · August 4th, 2009, 06:46 AM

I found this works best if you ground to a cable running perpendicular to the target you are going for (both unbonded from the ped).
This technique is great in hard soil when you can't get a grounding rod in, or in the urban jungles.

**scap** · August 13th, 2009, 07:59 PM

Originally Posted by TheCableVine

If I am understanding this correctly, that is one of my favorite techniques.

If I have two cables in a ped, one going east and one going west, I will unbond them and hook red lead to one cable and the ground to the other and then locate away. It works great.

It doesn't work for two cables traveling in the same direction or parallel in any way. I wouldn't recommend it anyway.

The reason I believe it is frowned upon is because you don't really know what is going on at the other end of the cables and you don't know if you have a completely separate ground.

This works like a charm.

I never do it, honestly...Really, I never do, because 65.5 will normally light up the same stuff for me on a RD, I have no need to get on the same line with both leads .....but you can locate shit for miles with that method

**Hoosier Locator** · August 14th, 2009, 06:26 AM

Sometimes you got to do what you got to do! Every locate it different .

**phoenix827** · August 14th, 2009, 05:57 PM

ok, maybe you guys get better info then we do, how do you KNOW which line goes in which dir? Only way I can see is to unbond everything and trace 1 @ a time.

**FiosKing** · August 14th, 2009, 06:26 PM

Originally Posted by Red105

i few months ago, i was shown a technique by another locator from a different district.

when locating a phone cable, in a situation where we could not get continuity and had tried almost everything, he proposed that we "double hook."

the locator took the black lead from the ground rod and clipped it to the bond strap attached to the other end of the cable in the pedestal... one end had the red lead, the other end the black lead and we had super continuity, where the rycom transmitter almost shorts and shuts itself off.

we located the cable out just fine, but he told me not to tell anyone that HE (specifically) had shown me that technique because he said that it was against company standards for an acceptable hookup.

why did hooking both leads to the two ends of cable give us such great continuity and why would it be an unacceptable setup?

good way to get a damage

**Octorok** · April 22nd, 2010, 03:40 AM

Just remember to "walk backwards" when targeting the cable attachted to the negative lead, otherwise you'll
be picking up the amperage in reverse which may offset your signal 6 to 12 inches.

BTW: Only use a ground rod when you have to, an opposing isolated cable is actually the safer bet.
That is unless you need accurate depth readings, then definitely use a ground rod.