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Posted By: MinElectrcn Circuit tracer failed - 04/02/03 03:22 AM
JUST WANDERING IF THERE ARE ANY OF YOU THAT TRUST YOUR TRACER LIKE I DID? I AM LIKE MOST AND THINK THAT THEY ARE ONE OF THE BEST TOOLS ON THE TRUCK AT TIMES. MINE HAS GOTTEN ME THROUGH SOME SITUATIONS THAT MADE ME WONDER HOW I EVER GOT BY WITHOUT IT. BUT TODAY I GOT A TASTE OF JUST HOW WRONG THEY CAN BE TO. I HAD TO RUN A CONDUIT FOR A 60HP, 3Ø 480VAC MOTOR FROM THE MOTOR TO A CLASS 1 J-BOX AND SPLICE TO THE WIRE FROM THE MCC FEED. SOUNDS EASY ENOUGH I THOUGHT TILL I GOT READY TO CUT THE OLD FEED IN THE BOX. NO LABELS ON ANYTHING AND SEVERAL WIRES INSIDE TO CHOOSE FROM SO I GOT OUT MY CIRCUIT TRACER AND PUT IT ON THE FEED IN THE STARTER CAN AND THE TRACER ONLY GAVE SIGNAL ON ONE SET OF CABLES. THANK GOD I AM FIRM ON PROPER PPE AND WAS WEARING IT BECAUSE AS YOU MIGHT GUESS IT WAS A FEED TO ANOTHER MOTOR IN THE BUILDING AND IT FOUND ITS ONLY DESIRE... GROUND! MORAL OF THE STORY I GUESS IS DONT PUT TO MUCH FAITH IN THESE DEVICES, THEY ARE WORTH THEIR WEIGHT IN GOLD WHEN THEY WORK BUT CAN ALSO BE SO WRONG!!!
Posted By: rj Re: Circuit tracer failed - 04/02/03 03:58 AM
I always double check to make sure that I have found the correct circuit with a meter before cutting any wires. The locators are nice but ever once and a while you will not find the circuit you want the first time.
Posted By: MinElectrcn Re: Circuit tracer failed - 04/02/03 04:12 AM
I DO ALWAYS CHECK FOR 0-ENERGY BUT THE WIRES IN THIS CASE WERE PASSING THROUGH THE BOX AND BECAUSE OF THE LABEL ISSUE I USED THE TRACER. I DID HOWEVER VERIFY THE CIRCUIT I WAS SUPPOSED TO CUT BOTH IN THE FIELD AND THE STARTER AND HAD LOCKED THE STARTER OUT. JUST WAS WRONG ABOUT THE PASS THROUGH WIRES. I WOULD NORMALY USE A "TICK"
TRACER IN THE BOX AS WELL BUT IT NEEDED TO BE INTRINSICALLY SAFE FOR THE CLASS 1 AREA
AND MINE IS NOT. BUT THEN THE ARC FLASH WASENT EITHER.
Posted By: Bjarney Re: Circuit tracer failed - 04/02/03 04:29 AM
I assume this thread deals with AC non-contact voltage detectors. Like any other tool, they are of very limited use without adequate training and experience. Their use always takes common sense and skill to be effective. The technology is applied in AC testers up to 800kV that folks trust their lives on every day. It is crucial to understand both their capabilities and limitations. They are not absolutely perfect and the user has to able to intelligently judge situations where they may give false readings, or not respond as anticipated.
https://www.electrical-contractor.net/ubb/Forum1/HTML/000133.html
https://www.electrical-contractor.net/ubb/Forum1/HTML/001999.html



[This message has been edited by Bjarney (edited 04-02-2003).]
Posted By: HotLine1 Re: Circuit tracer failed - 04/02/03 04:31 AM
Are you counting your blessings????
Cut a live one in a Class 1 area??
Intrinsically safe "tic tracer"????
Didn't know anyone made one.
John
Posted By: US Coreman Re: Circuit tracer failed - 04/02/03 03:55 PM
My electricians were tracing an open in a 3 ph 480V cct in a parking lot. It originates in a large metal building with a dozen panelboards in it. They too rely on the Tic Tracers, hell, I purchasedthe ones they use for them. But in a manhole or handhole full of other circuits, with someone turning on and off the source breaker, they were just spinning their wheels. They would get signals in one place and not the other, but when they cut open the circuit, they were wrong. I kept telling them to not rely on them. I also have analog & digital versions of 3M Dynatel cable path locators they tried to use. Finally, I just told them they have to fall back on our old methods as this was just starting to cost too much. The parking lot is about 30 acres and only some of the circuits are tagged. I guess the last straw was when one of my electricians used his own Harris telephone type tone generator and toner. He forgot to pull it from the line side of the panel they were trying to locate before he energized the feeder breaker, and, you guessed it, let the smoke out. Within 4 hours they had located the burned up cable, and that was that. In this case, nobody got hurt, but they could have if they had trusted the ticker only.
Posted By: MinElectrcn Re: Circuit tracer failed - 04/02/03 11:11 PM
I FEEL I MAY NEED TO CLEAR UP SOMETHING THAT IS STARTING TO GET OUT OF HAND. I DID CHECK THIS CIRCUIT FOR 0 VOLTAGE AT THE STARTER, AND IN THE MOTOR AS WELL WITH MY FLUKE 787. THE PROBLEM CAME ABOUT IN THE J-BOX THAT THE FEED WIRES PASS IN BEFORE THEY ENTER THE CONDUIT THAT RUNS UNDER THE CONCRETE TO THE MOTOR AREA. THE TRACER I USE IS A GREENLEE 2011 PRO CIRCUIT SEEKER AND I HAVE USED THEM FOR A LONG TIME AND ALSO HAVE HAD ALOT OF TRAINING IN THE PROPER USE OF ALL OF MY TEST EQUIPMENT. I WOULD NEVER TRUST MY LIFE ON A "TIC" TRACER OR MAKE ANY FINAL CALLS BASED OFF OF THE READINGS FROM THEM ONLY. THEY ARE AN AID ONLY. THE CIRCUIT TRACER CAME INTO PLAY TO TRY AND FIGURE OUT WHICH CIRCUIT IN THAT BOX I DE-ENERGIZED. IF I CAN FIND ONE END OF A CIRCUIT, MY FLUKE IS ON IT.
Posted By: SJT Re: Circuit tracer failed - 04/04/03 07:50 PM
It sounds like your carefull with testing and protective clothing etc. You mentioned the box you were in had 480v. I know sometimes things get crazy, but if possible do a shut-down on it before working. This can be scheduled with the owners, boss or who ever. 480 won't give you a second chance. Play it safe.
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