DANGER IN POWER LINES

Nelson Evening Mail, Volume LXVI, 15 February 1933, Page 3

DANGER IN POWER LINES

ASHBURTON ENGINEER’S WARNING EXAMPLE OF RECENT ACCIDENT A warning that anyone who fouled electric wires should immediately stand clear and communicate with a power supply authority so that the current might be cut off was given by -Mr II G. Kemp, engineer-secretary ’,o tin Ashburton Power Board, when dismissing with a representative of “The Press” the circumstances of the Mitcham road tragedy, as a result of whim two men lost their lives when u threshing mill came in contact with a 6000 volt electric wire.

“In the light of this accident them is a bigger hazard in connection with mills than we suspejeed,’’ sf.id Mr Kemp. Referring to the case in question, he stated that there wn- a c-ri-cuit-breaker on this particular feeder line in the power house, but there was not enough current flowing through the machine at the time to operate it. The top of the elevators was insulated from the ground by a piece of the wooden structure which intervened in one of the wheels of the combine. In addition to that there was a high ground resistance owing to its dry state.

THE RECENT ACCIDENT Before the current was ?ut off the combine was examined by the Board’s inspector, who found that only at one point did the axle reach a state of white heat, while the wood that intervened between the hub of the wheel and the rest of the frame was charred 1 a very small amount considering the contact had then taken place for one hour and three-quarters. The trouble resulted chiefly from the fact that the elevators picked up one of the wires and separated it from the other. If the wires had been carried a why togetherd the circuit-breaker would automatically have operated. There had to be an excess flow of current either to the ground or between the wires to make the cirucit-breaker operate, but in this case there was neither, said Mr Kemp. Added to this was the fact that the ground resistance was very high. “We have been living in fear of accidents, and have been issuing warnings at every opportunity,” said Mr Kemp, “although we did not contemplate trouble of this nature. We have about six cases of wires being pulled down every season.

' OWNERS ALREADY WARNED 1 “Only last month we issued the following warning to mill-owners ‘During each threshing season a number of cases occur of mills fouling electric power wires, resulting in broken wires and poles. The Board has instructed me to impress on you the grave danger to life which exists when damage is done to electric power lines. Even low-tension lines, carrying 400 arid 240 volts, are dangerous, while should hightension lines of 6600 and 11,000 volts he brought down there is little chance of anydne coming in contact with them surviving. In the interests of both of yourself and of your men it is very important that every care should be taken not to foul power wires,'especially when travelling at night.’ ” Continuing. Mr Kemp said that one of the chief dangers was that on some mills the drivers would not lower their elevators sufficiently to allow plenty of clearance under electric wires, which wore the regulation height of 18 feet above the ground. None of the wires in the country districts was insulated, and people had to realise that there was grave danger' for anyone coming in contact with them. Several cases' had been reported where mill hands had held up wires with a fork to allow parts of the machine to pass under, and that was a very dangerous habit. On the other hand, some mill owners never had any trouble, as they always travelled with their elevators at a height which gave them no cause for worry.