From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Observations on the fusing amperage of various gauges of single and double wire fuses for distribution boards.
| Identifier | ExFiles\Box 65\2\ scan0151 | |
| Date | 16th November 1928 | |
| To E.{Mr Elliott - Chief Engineer} from EFC. V.{VIENNA} BY.{R.W. Bailey - Chief Engineer} BY/RD. X7740 EFC3/T16.11.28. DISTRIBUTION BOARD. X7740/1 Further to our EFC2/T2.11.28, with reference to double and single wire fuses for the main and accessory distribution boards respectively, with a view to arriving at a gauge of double wire which is equivalent to our single 30 S.W.G., we have made the following observations. In the same circumstances in which a single strand of 30 SWG. fuses at 32 amperes, a double strand of 36 SWG. fuses at 23 amperes, and a double strand of 34 SWG. fuses at 43 amperes. It would therefore appear that the equivalent required is a double strand of 35 SWG. which presumably would fuse at about 33 amperes, the single strand going perhaps at 16 amperes. When we have your confirmation, we shall be able to put on order a quantity of this wire for this purpose, but it is no use doing so unless it is required. EFC. | ||