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).
Continued discussion on vehicle electrical distribution, fuses, and conductor sizes.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan200 | |
| Date | 22th April 1929 | |
| EFC2/T22.4.29. -3- Contd. -------------------------------------------------------------------------------- supplied through any other fuse on the main distribution board except the main battery fuse, the fuses on the accessory distribution board being of the same size and of equal importance with those others. We should then take the starter relay current from the point on this distribution board not supplied through the ammeter. The Klaxon could normally be supplied from one of the fuses in the accessory distribution box supplied through the ammeter (since the Klaxon current is q not quite so heavy), but if for any reason a horn taking more current were utilised, it could readily be changed over to the same point as the starter current wire. The wire passing on to the body light junction box would naturally be taken from one of the points supplied through the ammeter. The coachbuilders could be instructed not to touch the main distribution board but to connect any other apparatus which could be connected to the accessory distribution board to terminals corresponding to whether the current was desired to pass through the ammeter or not. In regard to the sizes of load conductors, we wish to lay stress on the point that conductor sizes should be chosen in relation to the sizes of fuses in their circuits rather than to the amount of current which the conductors have to feed.(i.e. the conductors must be heavy enough to cause the fuse to go if a short circuit occurs, rather than allow the conductor insulation to be burnt with consequent danger of fire). If, as we do, use size 30 S.W.G. copper fuses, and | ||