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).
Modifying a Bijur dynamo by inserting a 4-ohm resistance into the field circuit.
| Identifier | ExFiles\Box 38\3\ Scan012 | |
| Date | 23th May 1918 | |
| To R.{Sir Henry Royce} from EFC. c.c. to CJ. X. 3362. EFC2/T23.5.18. X.3231.-BIJUR DYNAMO. X 3360 X 3360 As a result of our R3/G17518, I have had the Bijur dynamo back on the bench and opened out the field circuit in order to insert resistance. I find that a resistance about equal to that of the field magnet winding, viz. about 4 ohms, improves the operation of the regulator as regards sparking at the contacts, and am therefore arranging for a resistance of this magnitude to be permanently included in circuit. The only other difference is, the dynamo has to run at a slightly higher speed before cutting in etc., but the speed is still well below the 1400 r.p.m. at which we have arranged to drive this dynamo. My reason for not putting in this resistance before was that I wished to keep the number of external resistances down to the minimum that was absolutely necessary. I am, however, arranging for this additional resistance to be inserted without interfering with the resistances that have been already made up. EFC. | ||