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).
Particulars of windings for the green lamp scheme and the auto charge control switch for 12-volt systems.
| Identifier | ExFiles\Box 59\1\ Scan285 | |
| Date | 16th March 1928 | |
| X4088 To EY/RD. from EFC. E.{Mr Elliott - Chief Engineer} Hoyle, RHC{R. H. Coverley - Production Engineer} EFC2/T16.3.28. PARTICULARS OF WINDINGS FOR R'S GREEN LAMP SCHEME & THE AUTO CHARGE CONTROL SWITCH. THESE WINDINGS BEING IDENTICAL FOR 12-VOLTS. X4040 Will you kindly note that as a result of further consideration of the utility of Eureka wire winding in series with the copper wire winding (the Eureka wire being on the pivot bobbin and the copper winding being on the armature bobbin) we now specify, for this purpose, the following :- The copper wire winding on the armature or present shunt coil bobbin is to be wound with 28 SWG. DSC. copper, filling up the space to just a reasonable degree without specifying any particular number of turns. Likewise the pivot end bobbin (which on the cutout is wound with a series coil) is to be wound with Eureka wire No. 24 SWG. DCC. This, in the case of R's green lamp scheme, will also fill up the space to a reasonable degree without definitely specifying the number of turns. In the case of the auto charge control switch, just sufficient space will be left to enable a winding of 12 feet of 30 SWG. DCC. Eureka wire to be placed over the other, this winding constituting the field resistance winding which is inserted by the auto switch. The particulars of the beginning, ending and directions of these various windings are to be as arranged between Mr. Davis and Mr. Allen as the standard directions in which these pieces of apparatus are now being wound. I think these have already been specified by Mr. Davis. We have plenty of wire for immediate needs of both sizes mentioned above. EFC | ||