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).
Experiments on the field fuse in a Lucas switchbox to test its current carrying capacity.
| Identifier | ExFiles\Box 61\2\ scan0430 | |
| Date | 13th December 1920 | |
| X2515 To Hs{Lord Ernest Hives - Chair}/TMW. from EFC. c. to EP.{G. Eric Platford - Chief Quality Engineer} c. to EP{G. Eric Platford - Chief Quality Engineer}/Mr. Wyer. c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} X.3749. X.2515. RE FUSE IN LUCAS SWITCHBOX. X.3743b. During my run on 2.EX Car this weekend, I made some experiments on the field fuse in the Lucas switchbox with a view to satisfying myself as to the sufficiency of the current carrying capacity of the fuse wire which we now send out as standard. In the first instance, I took a piece of the old wire which is of distinctly less fusing current than the present, and placed this in the fuse holder in a bad way so that it sagged and gave about 20% more length of wire than if it had been straight. I succeeded in causing this fuse to go once, but on replacing this fuse wire in as nearly as I could judge an exactly similar manner, I could not get it again to go, and of course it would not go when properly placed in the fuse holder. There was, therefore, no object in demonstrating that the fuse would stand up if the correct wire were put in and put in correctly, as everyone agrees that the fuse wire now supplied is of better current carrying capacity than the old. We are, therefore, satisfied that the present wire is correct for the purpose. Seeing, however, that it had been rather cold at the weekend and in any case owing to the watts expended in normal operation of the Lucas cutout, we still favour the placing of the suggested hole in the Contd. | ||