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).
Questioning the effectiveness of a second fuse added to a new type of Lucas switchboard.
| Identifier | WestWitteringFiles\C\May1919\ Scan65 | |
| Date | 20th May 1919 | |
| To R.{Sir Henry Royce} from EFC c. to CJ. c. to Bn.{W.O. Bentley / Mr Barrington} c. to E.{Mr Elliott - Chief Engineer} c. to BY.{R.W. Bailey - Chief Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to Da.{Bernard Day - Chassis Design} c. to EH. ORIGINAL. X. 3014 - LUCAS SWITCHBOARD - NEW TYPE On the new type Lucas switchboard which the Lucas Co. are supplying to us for the first ~~two~~250 HP. cars, we find that there has been provided a second fuse connected in the control circuit; the two fuses are of the same gauge and length. Although ~~w~~we have not tried this board with the dynamo on the bench, we do not see how anything is gained by the addition of this second fuse. If the main connections to the battery are broken, the current to the negative brush is always greater than the control current approximately by the amount of field current, and therefore, should the current be large enough to cause the fuse in the negative wire to go, the fuse in the control wire will remain intact because the current in the control wire will be immediately reduced in value on the parting of the first fuse, and conditions will be as bad as if no fuse existed in the control circuit. EFC. (Upside down text at bottom): R.R. 235 A (100 T) (S.E. 575, 16-4-19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2354. | ||