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).
Testing a modified Lucas LR.7 type regulator to reduce the effect of temperature on its output characteristic.
| Identifier | ExFiles\Box 166\2\ img145 | |
| Date | 10th January 1938 | |
| 6142 To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/RC.{R. Childs} c. By/RD. Rm{William Robotham - Chief Engineer}/RC.{R. Childs}1/MH.{M. Huckerby}10.1.38. LUCAS REGULATOR. We have received from the makers, and tested one LR.{Mr Ellor}7 type regulator, which has been modified for the purpose of reducing the effect of temperature on the output characteristic. As before reported, the outstanding objection on our part, to the Lucas regulator, was the big effect of temperature on the operating values of the unit, and we had repeatedly urged the makers to reduce it. A number of attempts to do this, without altogether redesigning the regulator on the lines of a larger unit with heavier windings were made; chiefly by means of thermostatic control in the form of a bi-metal hinge spring. Generally this method proved to be unsatisfactory, but a method has now been tried, which as far as this one unit goes, is satisfactory. This new method is quite simple, and consists merely of increasing the ratio of 'swamping' resistance connected in series with the shunt winding to shunt-winding resistance. The reduction in temperature effect obtained in this way can be seen from a comparison of the output currents at 13 volts, in the cold and hot conditions, with both normal and increased rations of 'swamping' resistance to shunt resistance. Regulator LR.{Mr Ellor}7. No.III. Output current at 13 volts. Normal resistance ratio (2 : 1) { Cold 13.3 amperes. { Hot 18.0 " Increased ratio (3 : 1) { Cold 13.3 " { Hot 15.0 " The rise in regulated current with temperature has been reduced from 4.7 amperes to 1.7 amperes. This Represents a satisfactory | ||