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).
Optimal wiring arrangement for accessory apparatus, particularly concerning the ammeter and fuse board.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan198 | |
| Date | 22th April 1929 | |
| To R.{Sir Henry Royce} from EFC. c. E.{Mr Elliott - Chief Engineer} SG.{Arthur F. Sidgreaves - MD} c. PN.{Mr Northey} Da.{Bernard Day - Chassis Design} c. Wor.{Arthur Wormald - General Works Manager} By.{R.W. Bailey - Chief Engineer} c. Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork} ORIGINAL WIRING OF ACCESSORY APPARATUS. There has been some amount of discussion, and possibly slight difference of opinion, concerning the exact arrangement of the wiring for the accessory apparatus. Two questions are principally involved : (1) As to whether certain apparatus shall or shall not be fed through the ammeter. and (2) Concerning the accessory distribution fuse board and fuses. Having considered the matter we are of the opinion that the arrangement most nearly meeting the various demands should be as follows :- Generally speaking it appears advisable that relatively steady currents in relatively continuous operation should be shown by the ammeter, whereas intermittent currents which are usually of larger magnitude than the steady ones should be bye-passed from the ammeter. There is some reason in this in that the steady continuous currents probably represent a far bigger discharge from the battery than the intermittent ones which are usually on for a short period. Secondly, it is expedient not to introduce another size of fuse of smaller denomination than our present single strand of 30 S.W.G. for main distribution, which means that the fuses on the accessory distribution box will be of that same value. That being the case, it is illogical to supply these three fuses through one single fuse of the same value on the main distribution board, and it is our recommendation | ||