Lightning Arresiers.

Radio Record, Volume II, Issue 7, 31 August 1928, Page 31

Lightning Arresiers.

JN a recent issue attention was drawn to a case where a lightning arrester saved a dweiling, or at least a radio set from fire. The lightning question, with outside aerials, need not be feared, providing the simplest of precautions is observed. But the ques: tion goes further than this: it is absolutely essential that every lead-in wire from an outside aerial shall be provid. ed with a lightning conductor. This is stipulated in the Radio Installation Rules of the Fire Underwriters’ Association. Failure to observe this simple precaution may mean the loss of all fire insurance money. As this regulation applies to any receiving station (crystal or valve) operating from an aerial, it is worth noting. Suitable protective devices, which will break down and cause an "earth" at 500 volts, are easily procurable for about half-a-crown. One is worth installing; it may return good interest. Other points worthy of note from the underwriters’ regulations are :-d All aerials, stay wires, counterpoises, and leads are to be placed so that they cannot connect with telephone or electric power lines. Indoor antennae must not be eonnected to gas or electric fit- tings. The leud-in from the aerial must be insulated.

As earths, both gas piping and the earth for the electric installation, are barred. The metal containing case of battery eliminators must be earthed. The fire underwriters’ inspector has the rigfht to examine any radio installation at any time. Looking over the regulations as a whole, they are merely an enumeration of the points an average person would take. If in doubt, a copy of the regulations is available from the Council of Fire and Accident Underwriters’ As: cosiations, Wellington, but in all probability your dealer could settle the question.