The Electric Set

Radio Record, Volume V, Issue 3, 31 July 1931, Page 12

The Electric Set

Connection with Mains APROPOS a question raised recently concerning the connection of all-electrie radio sets to the mains, our attention has been drawn to a similar point which was raised in the "New Zealand Electric Journal" a short time back. This was the question:"Will you please advise what ise necessary to comply. with the wiring’ regulations in connection with all-,/ electric sets to the supply?" The answer was:"They must be connected to the permanent Wiring by means of a plug and socket, except that for demonstration purposes when a set is being offered for sale, it may be temporarily connected to a lampholder by means of an adaptor, provided the current taken does not exceed one ampere and that a person touching any metal liable to become alive is not likely, under normal conditions, to be simultaneously making contact with earth other than the a earth used for reception purposes on the set itself. "The flexible cord used shall be of oval or circular section of high insulation and carrying capacity, and shall be protected with hard-co- * braid-

ing, tough rubber compound or wiré armouring. "Transformers used to connect the set to the supply must be double-wound, and the winding connected t- the stpply must be effectively separated from all other windings. "The transformer must be earthed. "All exposed metal liable to become alive must be earthed. Where the only danger of contact with earth is due to the earth used for reception purposes on the set itself, the metal liable io ° become dlive may be connected to the earth terminal of the set. "If fuses are used they must comply with the regulations." The radio enthusiast should take notice of these regulations, as, in the event of a fire, inquiries are likely to be made, and any departure therefrom might put him in ill-favour with the Underwriters’ Association when it comes to the matter of insurance.