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).
Preventing damage from interchanging main and field fuses on a distribution board.
Identifier | ExFiles\Box 36\4\ scan 124 | |
Date | 25th August 1920 | |
Contd. -2- EFC1/T25.8.20. immediately relieve the excitation of the machine. X.3555. X.3923b. There is the possibility on the distribution board on 6.EX that the main fuse and field fuse might be interchanged in error, in which the case field fuse in the main fuse position would very readily go, after which the dynamo would roast itself because the main fuse in the field fuse position would not go. This would suggest making the two fuse holders non-interchangeable, The arrangement of main fuse and field fuse, described and shown diagrammatically on our small photostat diagram dated 8.4.20, and send to you under cover of our EFC2/T8.4.20, is the one which we believe to give the best overall protection to the dynamo battery system. (Excluding faults on the lighting wiring, for which further distributing fuses would be used if thought necessary). The field fuse being rather fine is difficult to deal with if of copper wire, especially in the Lucas fuse holder. This difficulty, however, is not so serious in the case of the R.R. type of fuse holder, and we are therefore collecting together samples of every gauge of copper wire which fuses at less than 40 amperes in the R.R. fuse holder. We are going to carefully tabulate the fusing currents of these with a view to arranging for copper wire fuses in all our experimental distribution boards. Your further telegram now to hand. EFC. | ||