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).
Insulated ignition tubes, earthing, and the prevention of subsidiary sparks and potential fire.
| Identifier | ExFiles\Box 61b\4\ scan0196 | |
| Date | 14th November 1919 guessed | |
| -4- Contd. We have tried an actual insulated ignition tube in the same way and we find the same results, making due allowance for the fact that the wires do not all pass right through the tube. We do not think that the insulating covering on the tube is electrically necessary, and can see no reason why it should be. We do, however, consider that the ignition tube should be definitely earthed at each end; if insulated there is a possibility of little sparks taking place between the tube and any other piece of metal in its neighbourhood which might even, under some circumstances, cause fire. In every case the subsidiary sparks are reduced in intensity and finally put out by gradually reducing the length of the main sparking gap and therefore the potential of the principal wire. EFC. | ||