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 dynamo testing, battery charging capabilities, and separator arrangements in Exide and P&R batteries.
| Identifier | ExFiles\Box 54\1\ Scan052 | |
| Date | 24th November 1925 guessed | |
| -5- Contd. replace the other machine on our experimental study of dynamos. You could then run throughout the winter with this machine, and I should ask you to imitate as far as possible the extreme conditions that might be met with in Town running. You will understand, of course, that in this connection we are not regarding you as a customer, but as a battery manufacturer. It would be interesting and valuable information to us to know as a positive fact that with such a setting the battery would be capable of meeting all the demands made upon it without being undercharged. I should then probably be ready to admit that the output as arranged, in accordance with the dotted curve sent to you, is unnecessarily large, but at the moment, in the absence of such evidence I can only say that I should be very dubious about this being more than sufficient. You say you have had a good number of batteries back, both of your own make and of Exide. Until quite recently we have been patting ourselves on the back that since we arranged the new standards of batteries we have had practically no trouble, though lately I have heard one or two vague reports of trouble, and as a matter of fact, more particularly of P & R batteries, but I have had no official information of cases of failure. I am now making a move to try and obtain information of such cases more directly, as I feel that such information ought to come to me, as it would be valuable for obvious reasons. Regarding the suggestion of adopting the arrangement in the Brolt set; quite early on, before the new PhantomCodename for PHANTOM I switching was arranged, I suggested this to Mr. Royce for adoption. I quite agree that it is a good scheme to charge at a higher rate when the head lamps are lighted. The objection to it was that we wanted to keep the two systems (40/50 and 20 HP) alike, and that this would mean an extra gadget, viz. an extra field resistance. With regard to your P.S. In every case the ebonite separator is against the positive plate, as we have always understood. From observations through the vent-holes of up-to-date standard Exide and P & R batteries, we note that the 40/50 Exide battery has wood separators ribbed on both sides, i.e. ribs in Contd. | ||