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).
The combined operation of a dynamo and cut-out, with test results under cold and hot conditions.
| Identifier | WestWitteringFiles\F\February1921\ Scan102 | |
| Date | 14th February 1921 | |
| Contd. -5- EFC2/T14.2.21. The behaviour of this regulator in other respects seemed to be very good, but it appears that this phenomenon would comdemn this particular feature. We have also investigated the combined operation of dynamo and cut-out in the usual way with the following results :- (1) Dynamo voltage and speed at which cut-out was just operated. Cold. 11.3 volts 340 R.P.M. Hot. 12.4 volts 375 R.P.M. (2) Voltage of system at this speed and battery current after operation of cut-out. Cold. 12.2 volts -1.6 amps. Hot. 13.2 volts -.9 amp. (N.B. - implies reverse current). (3) Dynamo voltage and speed at which cut-out just fell away, and reverse amperes from battery. Cold. 11.7 volts 280 R.P.M. -3.5 amps. Hot. 12.4 volts 305 R.P.M. -3.4 amps. (4) Dynamo volts at this speed after falling away of cut-out. Cold. 9.0 volts. Hot. 9.5 volts. To compare with the above it should be stated that the balancing speed at 12.4 volts cold is 370 R.P.M. and at 13.6 volts hot is 405 R.P.M. It will be seen that both cold and hot the cut-out is too early in operation. The change of cutting in point with temperature seems not to be too great. Shunt coil resistance is about 60 ohms cold, 68 ohms hot. EFC. R R 582v (100 L) (2 H 189 17-8-30) G 3800 | ||