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).
Blueprints of performance curves for a 20 HP dynamo fitted with an automatic electro-magnetic switch.
| Identifier | WestWitteringFiles\Q\December1926-January1927\ 61 | |
| Date | 21th December 1926 | |
| To R.{Sir Henry Royce} from EFC. c. to BJ. E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} By.{R.W. Bailey - Chief Engineer} c. to Oy. De. c. to EP.{G. Eric Platford - Chief Quality Engineer} PN.{Mr Northey} EFC2/T21.12.26. ORIGINAL AUTOMATIC ELECTRO-MAGNETIC SWITCH FOR REDUCING THE RATE OF DYNAMO CHARGE. Further to our EFC1/T4.12.26, herewith please now receive blueprint of major and minor curves for the 20 HP. chassis, the major curve being the representative output of our standard 20 HP. dynamo at 80°C (temp. as measured in the usual way on the bench), and the minor curve being the output as reduced by the resistance inserted by the auto switch. The minor curve is also taken at 80°C. and both curves are taken to the operating voltages corresponding to various ampere outputs indicated on the vertical scales. The two units referred to as having been handed over to be fitted one each to a 20 HP. and a 40/50 HP. car, are now so fitted, and the operation of these is under observation. EFC. Blueprint attached. | ||