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).
Re-design of the re-distributing board for 40/50 HP cars, moving to a single fuse system.
| Identifier | Morton\M3.6\ img025 | |
| Date | 16th September 1919 | |
| To EFC. from R.{Sir Henry Royce} Copy to CJ. " " BN.{W.O. Bentley / Mr Barrington} ORIGINAL. R4/G11/6/19. (4) X.3553- RE. DISTRIBUTING BOARD FOR 40/50 H.P. CARS. I think it will be the safer thing to do to adopt a four-point switch for the dynamo, as arranged by the Lucas people. Owing to the complication, we have decided to abandon the use of fuses for each of the circuits, and are arranging for a single fuse to be put on to the positive wire, leading from the battery to the distributing board, and a fuse on the earth connection. This fuse will be suitable for carrying the maximum current likely to be passing in and out of the battery from this board, which we think may be in the neighbourhood of 30 amperes, and a fuse of about 5 amperes (carrying capacity) in the earth connection. We have decided to put all switches on the positive, and to earth the negative of the battery by a connection from this board, so as to work the ignition. This earth connection will be manifest, and easily detachable for testing the insulation of the entire system. We have written a paragraph for the instruction book, referring to the electrical system, "that before attempting to disconnect or in any way work on the starter and other electric circuits, it is advisable to disconnect the positive lead from the battery. It will also be seen that an earth connection is made through a fuse on the distributing board; when this is removed, the whole of the electrical circuits should be insulated, except the battery ignition circuit, which is earthed every time the (Contd.) W W 3120 (200 L) (P D 408 50-4-11) HWV S172d/2 | ||