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).
Ignition system screening for a 20/25 Tank Installation.
| Identifier | ExFiles\Box 163\2\ img046 | |
| Date | 30th March 1933 | |
| WST 86008 To Mr. Eg. } from E.{Mr Elliott - Chief Engineer} c.c. Mr. By.{R.W. Bailey - Chief Engineer} Mr. D/BP. c/o.{Mr Oldham} Mr. Ha/Wst. E.7/HP.30.3.33. 20/25 Tank Installation.Screening. During the visit of Major Rowcroft, Chief Inspector of Armaments and his assistant Mr Sheryer, with F.{Mr Friese} to the works yesterday, we had some discussion with regard to the question of the screening of the ignition system. We do not know how far these gentlemen are able to influence the policy of the War Office but they have agreed to recommend a modified policy of improvement which would entail far less alteration than working to the official specification RE/PROV/3056. We showed them a specimen of armoured cable wound with phosphor bronze which we are testing in connection with our aero engine screened ignition wiring, and demonstrated its enormously increased resistance to mechanical damage as compared with the standard product wound with soft copper wire. They are prepared to recommend this P.B. wound cable which is of the existing standard diameter and does not demand any change in various fittings used on the ignition wiring system. To meet the provision for completely screened plugs we exhibited samples of different designs of plug screens which can be purchased to fit the standard size of cable, and it was decided that the Lodge type was the one most suitable for the job. At the same time it was understood that these cannot be recommended until a test has been made at our works on an engine to make sure that the electrical operation of the ignition is not impaired, and that the thermal conditions of operation are satisfactory for the type of plug normally used, or to find a plug that would be satisfactory in this latter respect. In the event of plug screening not being permissible due to these causes, Mr Sheryer asked that an improved form of earthed terminal, which has been developed for the aero work, might be adopted in place of the present type fitted to the Tanks, as the latter is said to be liable to failure | ||