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 Bosch Ltd. regarding a failure of a regulator on a 200W dynamo and requesting further technical information.
| Identifier | ExFiles\Box 60\4\ Scan123 | |
| Date | 15th December 1931 | |
| X4562 c. BY/RD. Hs{Lord Ernest Hives - Chair}/Wst.3/MA. December 15th, 1931. Messrs. Bosch Ltd. Larden Road, Acton LONDON W.3. Dear Sirs, We have had a failure of the Bosch regulator fitted to the 200 W dynamo we recently received from you. The contacts fused and broke contact due apparently to the dynamo becoming open-circuited. This open circuit as far as we can gather occurred owing to a fuse which was inserted in the main circuit, fusing and thereby disconnecting the dynamo from the switchbox and the battery. We had the impression that the one especially attractive feature of this automatic regulated dynamo was that in the event of the battery becoming disconnected the dynamo would continue to function without distress, but apparently this is not the case. We should like to have from you a little more technical information with regard to the operation of this system as we do not wish to impose unduly severe conditions of test. For instance:- (a) What is the maximum open-circuit speed at which this dynamo can be run without undue heating on the regulator points occurring. (b) Is it possible to satisfactorily run this dynamo under any conditions i.e. with lamp loads or just ignition load, without being connected to the battery. Upon perusal of the diagrams sent along with this machine we gather that it is not intended for a switch or fuse to be inserted in the dynamo-battery circuit. Therefore in this case the cut-out regulator unit is the only protection in the circuit and we consider this unit should be designed to cope with any open circuit condition. | ||