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).
Unfused wiring connection for illuminated instruments and proposing a safer alternative.
| Identifier | WestWitteringFiles\P\October1926-November1926\ Scan122 | |
| Date | 16th November 1926 | |
| ORIGINAL. To Da.{Bernard Day - Chassis Design} from EFC. EFC8/T16.11.26. X.8530 FRAMED INSTRUMENTS WITH INTERIOR ILLUMINATION N.Scheme 2224. On the above Scheme the connection to the indicating lamp, via the Cambridge thermometer, is shewn taken from one of the ammeter terminals. We presume you are aware that in so doing there is no fuse provided for this circuit, except the main battery fuse. Strictly speaking of course, such a circuit should come from terminal No.7 on the distribution board which is fed through a fuse, though that would be particularly inconvenient in this case. For the experimental tests it is being arranged as shewn on N.Sch.2224, and though it is perhaps unlikely that it would be any source of trouble, you will agree that it is really wrong in principle. One has to remember that the instrument cases are all earthed. EFC. | ||