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).
Programme of work for testing a 28 slot armature on an N.B. machine.
| Identifier | ExFiles\Box 68\4\ scan0031 | |
| Date | 10th January 1928 | |
| To CAP. from EFC. X.8672 EFC3/T10.1.28. PROGRAMME IN CONNECTION WITH 28 SLOT ARMATURE ON N.B. MACHINE. (1) Put back the 90° B angle 28 slot armature in N.B. J machine. Re-set the control brush to 122.5° as previously determined for maximum permissible output. Run machine on peak output on schedule volts. Note the peak output when 80°C is reached and take the (maximum permissible) curve at this temperature. Note further the increase in temperature and the loss of peak output when run continuously on the peak, still at schedule voltage. (2) Remove and replace this armature in one of the 12 machines representative of the average of those 12, and observe the performance and heating with the C angle as it is. (3) If all turns out O.K. we will have the other two 28 slot armatures altered to have a similar B angle to this one. EFC. | ||