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Stormed
10-15-2020, 09:47 PM
Currently employed as a CATV Lineman and we often deal with hot lines.

First question, more of a short story that I'd like some answers for.
We had a build around Clarion, PA. The electrical setup was decades old to say the least and one pole in specific was extremely hot. The issue here is that Phone, and Comcast were both hot to the touch off our insulted tools however even after adding in a VGR connected to Top Line and grounded to both Phone and Comcast the line remained hot, and based on our Voltage Meters hotter than before we had one on, from what I remember the meter was reading above 200 volts on the bare strand. What would be the main cause of this and what would be a key indicator to see this ahead of time, My initial theory was the main insulator for the service wires was bad/ground had been damaged but we never figured out.

Second question.
We had another build where our main strand line and guy-wire were both hot even after having our lines bonded to the VGR in two separate locations completing the continuity bond. Is this simply the voltage passing through the bonds or was the Power VGR at the ground/acorn simply just gone bad?

DaddyBruce
07-19-2021, 05:27 PM
Grounding and interactions with powerlines is a very complexed issue at times. Multi grounded system neutrals are attached in hundreds of places and interface to stabilize the electrical systems. All sources of energy are trying to go back home to earth. The terrain and earth is a variable and if your location is the best path guess what it attracts attention. If there are induction hazards or stray voltages of metal isolated and in a magnetic field they all are sources. Harmonics are in play as well. Loose hardware or spacing issues are just a few of the issues. Ground connections and corrosion become partners in all this. Using your voltage detection equipment with many times register in hundreds of volts. It all says that applying pole grounds can increase or decrease the hazard but with out doing lots of detective work it cannot be specifically answered. In the last twenty years homeless people also steal pole grounds for money. Poor people.
I know this is not a clear answer but I hope helpful.

rob8210
07-20-2021, 07:34 PM
Are you not required to install a ground rod every so often and then bond your messenger to it? In our little electrical world we are supposed to install ground rods every 5 to 7 poles and then install ground wires from the rod to them system neutral. Some places use ground plates , some coil wire to the bottom of the pole ( hot plate ) . Of course over time , depending on soil conditions , these connections do rot off. If you are only bonding to the electrical system , then the reliability of your grounding depends totally on the quality of the electrical system grounding. Many factors can cause voltage on system neutrals, bad grounding will not take it away. High voltage insulators will “ leak” voltage sometimes. When this happens this electrical leakage is trying to find its way to ground. Be aware, under the right conditions this voltage can be significant and therefore dangerous. Report it to the local utility.