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 the ineffectiveness of a ballast resistor as a fuse replacement in a constant current dynamo's field circuit.
| Identifier | WestWitteringFiles\D\January1920\ Scan18 | |
| Date | 1st January 1920 | |
| To CK.{Mr Clark} from R.{Sir Henry Royce} Copy to CJ. " " BN.{W.O. Bentley / Mr Barrington} " " OY. X 294 ORIGINAL RE CONSTANT CURRENT GENERATORS. X.3Y/6 X.2875 I am sorry you went to the trouble of putting the ballast resistance in place of a fuse in the field circuit of a constant current dynamo. This could not possibly have any good effect unless it were of the same nature as a fuse, and depended upon its protection properties by change of resistance from practically nothing to a very high amount, i.e. some material that will change its resistance with temperature enormously. I know of nothing sufficiently effective. R.{Sir Henry Royce} | ||