Several winters ago my wife kept telling me she got shocked every time she touched the shower head. I touched the shower head and never had a problem. I basically thought she was nuts until I happened to step on the drain while touching the shower head. I am a foot taller than her so when she was adjusting the showerhead she was always standing on the drain and I never was. I measured over 5 volts between the drain and the showerhead. We were living in an old farmhouse so I figured something was rubbing on something and started trouble shooting. We were on a well so I shut off the well pump, hot water heater etc. eventually turning the whole darn box off but found that I still had over 5 volts at the shower head. I had the electrician come out. He measured almost 5 volts with his better meter. He grounded everything (and I mean everything) with all copper rods, brass clamps and grounding cable he had on the truck and was only able to get down to around 3 volts. I called the power company several times telling them the problem. They had little interest in my plight instead telling me to call an electrician.
I really am a surgeon and often perform minor surgeries in the office under local anesthesia. Sitting still for 60 minutes is really boring so we try to have a relaxed OR with distracting conversation. We were just getting started when my wife calls the office and has the nurse relay to me that she put the trough heater in the new Rubbermaid trough (the old trough was galvanized metal) and now the horses will not drink at all. My wife had measured over three volts between the trough and the ground and wanted me to ask around and find another electrician. As the nurse is relaying this to me my patient starts to ask questions. I told him whole long tale. Turns out he is one of the senior inspectors for the power company. When I got home that night I had three power company trucks up by the barn. They finally found that I had a 50+ year old transformer that has essentially been forgotten by the power company. Om this transformer there was a bad ground wire on. They replaced the ground wire and the potential difference dropped to almost nothing. They said that when they replaced the transformer that it would be undetectable. The power company guys also told me that ground current is common and that it is a particular problem on farms. While it is rare to have enough voltage for humans to detect the problem comes from the fact that animals can detect very low voltages and will not drink from “hot” water.
I really am a surgeon and often perform minor surgeries in the office under local anesthesia. Sitting still for 60 minutes is really boring so we try to have a relaxed OR with distracting conversation. We were just getting started when my wife calls the office and has the nurse relay to me that she put the trough heater in the new Rubbermaid trough (the old trough was galvanized metal) and now the horses will not drink at all. My wife had measured over three volts between the trough and the ground and wanted me to ask around and find another electrician. As the nurse is relaying this to me my patient starts to ask questions. I told him whole long tale. Turns out he is one of the senior inspectors for the power company. When I got home that night I had three power company trucks up by the barn. They finally found that I had a 50+ year old transformer that has essentially been forgotten by the power company. Om this transformer there was a bad ground wire on. They replaced the ground wire and the potential difference dropped to almost nothing. They said that when they replaced the transformer that it would be undetectable. The power company guys also told me that ground current is common and that it is a particular problem on farms. While it is rare to have enough voltage for humans to detect the problem comes from the fact that animals can detect very low voltages and will not drink from “hot” water.
