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 to Mr. Minchin discussing the operation and adjustment of an auto switch for battery charging.
| Identifier | ExFiles\Box 59\1\ Scan222 | |
| Date | 4th January 1928 | |
| X. 4008 EFC5/T. 4th January, 1928. Mr. G.R.N. Minchin, 50, Grosvenor Gardens, London, S.W.1. Dear Mr. Minchin, Referring to yours of the 22nd. ult., I am pleased that you confirm our opinion that it is better from the battery's point of view for the battery to be charged at full rate and then come off charge altogether. I have had an auto switch under observation to some extent on a car which I ran during the Christmas holiday. For the first half of the time the battery was not up sufficiently for the switch to go over. The switch operated reasonably well, but I concluded that it required some adjustment, as it seemed to go over too easily. So far as we can see at present, the only question at all which arises in connection with this auto switch as at present arranged, is the question of being able to get reasonably right and consistently reliable adjustment for going over and coming back. We know we can have a good range and can always reduce the coming back voltage as far as we like to prevent it doing what you say, i.e. of keeping on coming back and going over again. There is no difficulty about this - it is just bound up with the question of adjustment only. We shall be making further observations on the same car to which we have temporarily fitted a suitable voltmeter connected across the shunt coil of the auto switch. Yours sincerely, | ||