Stoneridge Engineering Home |
345Kv line & electrostatic shocks
Posted by Mike Owens on 4/8/2004, 6:24 pm I'm a TV reporter in St. Louis doing a story about a family living in a home that has been constructed on the edge of a utility easement. The easement carries a 345Kv line owned by AmerenUE, the local electric utility. The family has been plagued by static shocks, and the homebuilder and his electrical contractor have been grounding various objects to protect the family. Grounded were the gutter downspouts and a mailbox. Still, the family is getting shocked in the yard, and one of their kids, while riding her bicycle, gets shocked too. The solution, provided by the contractor, was to ground the bike! The contractor says the surveyor failed to measure the site properly, and the house was built too close to the powerline. The utility says it's line is fine, and meets specs. My question, without opening the door to the EMF danger crowd: are the electro shocks a hazard, and would you live within 30 feet of a 345Kv line? Thanks... Mike Owens
|
Re: 345Kv line & electrostatic shocks
Posted by Bert Hickman on 4/8/2004, 10:59 pm, in reply to "345Kv line & electrostatic shocks" Hello Mike, That's an interesting story! High voltage transmission lines will indeed induce voltages and currents into nearby conductive objects. The larger the object, or the closer to the powerlines, the greater the amount. This can be a significant problem with larger metallic structures parallel to the lines, such as fences, gutters, or metal buildings and sheds. If these aren't carefully grounded, they can cause painful and even dangerous shocks. Although there is probably little real danger, initial contact with smaller ungrounded objects can result in an unpleasant stinging sensation or a "buzzing" feeling. Under some conditions, a small spark may even occur upon contact, similar to a small static electricity discharge. Although the voltages and currents are not particularly hazardous, the unpleasant sensation is certainly a nuisance, and it could be frightening to a small child. Personally, I wouldn't want to live 30 feet from a 345kV power line for a variety of reasons: because of the nuisance E-field effects, the higher ozone level, and the poorer house resale prospects. But I wouldn't be overly concerned from a health standpoint. Best regards, -- Bert --
|