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).
Providing commentary and suggested changes for a Phantom technical wiring diagram.
| Identifier | ExFiles\Box 168b\2\ img143 | |
| Date | 6th July 1928 | |
| 17560 To E.{Mr Elliott - Chief Engineer} from EPC. C. BY.{R.W. Bailey - Chief Engineer} EFC2/T6.7.28. 17560 PHANTOM TECHNICAL WIRING DIAGRAM. X4040 Referring to LeC.2570 sent under cover of E2/M29.6.28, we would like to comment upon this as follows :- (1) We think it a good idea to have double lines (close together) round the various units, as the boundary lines are not so easily confused with the lines representing wires. (2) The positive end of the instrument board light appears to be wrongly connected. It should be connected to one side of the push button switch on the switchbox, the other side of which is connected to the positive terminal of the inspection lamp socket, i.e. No.7. (3) The connections of the cutout appear to be wrong on this diagram. The A wire from the dynamo should go to the other side of the main contacts. Furthermore, we think the shunt and series coils should be distinguished from one another by thin and thick turns respectively. (4) We notice that the positive terminal of the green lamp contacts is, together with the positive terminal of the green lamp operating coil and the positive terminal of the cut-out shunt coil, connected to distribution box terminal B. If fuse No.1 is removed, or parts, while the system is working, the field is excited by the battery and we get a high voltage on both the coils and the lamp. The lamp would probably be burnt out and the coils possibly roasted. (We suspect that this has been the explanation of one or two cases which have occurred of charred cutout shunt coils on our present standard system, and we have recommended that the cutout shunt coil positive be connected to C, to avoid this possibility). We have this method of connection on experimental test on three experimental cars. In any case, we consider that the green lamp should be connected to some point on the system as near to the battery as possible, so that when there is a high voltage the green lamp may have more chance of being normally lit, i.e. not burnt out before it can be observed. We think that it might be connected to the ammeter side of the main battery fuse, i.e. terminal No.8. This is the method of connection we have on the two experimental units of this type. | ||