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).
And comparing different schemes for a charge indicator system.
| Identifier | ExFiles\Box 59\1\ Scan133 | |
| Date | 29th March 1927 | |
| EFC. ) To Hs.{Lord Ernest Hives - Chair} ) From R.{Sir Henry Royce} BY.{R.W. Bailey - Chief Engineer} ) At Le CanadelHenry Royce's French residence. X4008 R4/M26.3.27. DESPATCHED FROM WW. 29.3.27. c.c. to BJ Wor.{Arthur Wormald - General Works Manager} RG.{Mr Rowledge} DA.{Bernard Day - Chassis Design} CWB. PN.{Mr Northey} E.{Mr Elliott - Chief Engineer} 40/50 & 20 HP. CHARGE INDICATOR. X.4040. X.4008. I have written how anxious I am to push the above forward, to save the battery and the dynamo, and to reduce cost of filling up, and trouble with electrical units on our cars. While I think EFC. has worked hard and done well with the scheme he suggests, I am not in favour of fitting it for the reasons I have given. At one time I felt inclined to give way but it was to please others against my own judgement. I also think the voltmeter will be found to be neglected because the indications are too undecided. So we have as far as I know only two hopeful ones. They are (1) my inexpensive scheme which is so near like what we should do with a stationary battery, and which can do no harm even if one smashed it all up with a hammer, and (2) a scheme suggested by E.{Mr Elliott - Chief Engineer} of the electro-magnet to make a contact. I have added to it that we could have a green lamp, and we could cut off the electro-magnet when we shut off the charging switch. This scheme interferes less with the dynamos, and is simpler and safer, and enables the driver to know that he has a charge, and to entirely cut off his charging, and so thoroughly save his cells and dynamo, whereas one fears that EFC. only half does it, especially in the cases of long distance, high speed running. I would like both my schemes, and this latter one which we may call EFC's magnetic, with E & R's modification, to be known as the green lamp scheme, tested and compared. EFC's objection to my scheme is not important because if we do not overcharge we shall not crack the sealing of the control cell for many years. If we should do so, it it as well to know it because the cell would be near its life's end, also the indicator would fail slowly and do no harm, also the plug could be transferred if suspicion of leaking existed: everything has some possible failing. Our model has done so well that for the last 4,000 miles we have needed no water put in our cells, and whence probably saved considerable destruction to the cells. R.{Sir Henry Royce} | ||