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).
Modifications for a 4-coil loading switch for use on Exe, Vulture, and Merlin engines.
| Identifier | ExFiles\Box 163\7\ img304 | |
| Date | 1st December 1936 guessed | |
| -2- 4 coil loading :- The above figures are altered only in respect to the voltage lag which was 3.3 volts with the switch at 20°C. and 4.2 volts with the switch at 40°C. It will be seen from the above figures that to use this switch in conjunction with four coils on the Exe and Vulture it will be necessary to reduce the series winding turns by a half as these are now directly responsible for the increased voltage lag. For use on the Merlin the switch is now about right and should require no further electrical modification. The testing circuit used for the above tests is given below :- | ||