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).
Optimal wiring connection for a shunt coil in a distribution box based on experimental results.
| Identifier | ExFiles\Box 65\2\ scan0114 | |
| Date | 17th May 1928 guessed | |
| -3- Contd. We have also another and independent reason for connecting the positive end of the shunt coil to distribution box terminal C instead of B. This we have mentioned to Mr. Royce and we have the arrangement running on one or two experimental cars, but it is not yet standardised, the standard connection being to B, with field break first. (Case 1.). Although it is agreed that when the positive end of the cutout shunt coil is connected to distribution box terminal B, and the armature contact [handwritten correction: break] of the switch breaks first, we get no flash at the cutout [handwritten correction: switch], also that when the armature breaks first and the positive end of the shunt coil is connected to distribution box terminal C, the breaking of the field contact of the switch produces no flash, nevertheless in both cases we get the burning effect of the armature break on the switch. In the former case (Case 2) we get a field flash, and in the latter case (Case 4) we get some flash at breaking the cutout points. It is for these reasons, amongst others, that we consider Case 3 is the best alround. EFC. {E. Fowler Clarke - Electrical Engineer} | ||