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 Joseph Lucas Ltd. regarding a modification to dynamo field coils and regulator compatibility.
| Identifier | ExFiles\Box 166\2\ img241 | |
| Date | 14th January 1939 | |
| Regulator 6092. EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/RC.{R. Childs}5/JH. 14th. January, 1939. Messrs. Joseph Lucas Ltd., Great King Street, BIRMINGHAM. For the attention of Mr. C.C. Robinson. Dear Sirs, It has become necessary to modify the field coils on our large dynamo, and in doing so, we find that the resistance of the total winding is increased to about 7 ohms, as compared with 6.25 ohms on our present production machine. As this machine has to work in conjunction with your C.A.V. type of regulator on our Phantom car, we wished to ascertain the effect on the C.A.V. regulator of the higher value of resistance, before proceeding with the modification. We remember that you have given us a resistance of 6.25 to 6.50 ohms as being about the right value and we should be glad to know what you consider is the highest resistance we could safely go to on this winding. Further in case a similar modification should be introduced on the small machine, we would like to know whether the R.R.1. type of regulator requires any consideration in this respect. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||