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).
Letter discussing modifications to dynamo and switch schemes, and a 10,000-mile test.
| Identifier | ExFiles\Box 165\6\ img165 | |
| Date | 17th March 1928 | |
| X5666 Contd. This will reduce the temperature effect to about one fifth of its present value and we know that then the auto switch will be a jolly good job. Mr. Royce has, however, asked us to put on the next car what he calls 'EPC3/T green lamp scheme' where the switch, instead of doing the job itself, lights a lamp to warn the driver to do it. In addition to which an extra switch is then needed for cutting off the magneto, because the switchbox with that scheme will have M & B in the first position. Mr. C.R.N.Minchin, 50, Grosvenor Gardens, London, S.W.1. X6/80 Dear Mr. Minchin, I have your further letter of the 16th inst. I am interested in the fact that you are getting a 20 H.P. car later in the year - presumably for yourself. We are all very pleased here with the latest modification of 20 H.P. dynamos - I do not know whether I told you that we have succeeded in making it quite quiet - it satisfies those who produce it and those who do the testing, without any complaints. We shall gradually make a further modification to the 40/50 H.P. dynamo to get it to the same state. I do not mean to say there is anything wrong except very slightly, but that we have got the 20 H.P. dynamo to a tip-top state - everybody says it is a thundering good job. I am sending Mr. Bellringer a letter as attached, together with two copies of the instructions, and also enclose a copy of these instructions in the form of a report from my assistant for yourself. I am also interested in your remarks on the tungsten points. You may know that we have standardised a big improvement in the mechanism of this contact breaker by which the advantage of the tungsten points is very much enhanced. The points on the recent 10,000 mile test in France have not been touched in any way at all - in fact there has been no trouble whatever on this test with the electrical system. Incidentally it incorporated an auto switch. This exhibited a slight fault which we knew of quite well beforehand, viz. the temperature fault, which we are now correcting by the use of Eureka wire winding in series with the main shunt winding. Contd. | ||