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).
Test results for a cut-out component, detailing current and voltage measurements under various conditions.
| Identifier | ExFiles\Box 48\3\ Scan166 | |
| Date | 1st December 1920 | |
| Contd. -7- EFC {E. Fowler Clarke - Electrical Engineer} 1/T6.12.20. Similar results to those already taken were now taken with this changed resistance. The operating voltage and current in the cold condition would, of course, be unaffected, but the current after operation was reduced in accordance with the increased resistance. The shunt current now to de-operate (with battery disconnected) was only a trifle less than the same current immediately after operation, i.e. the volt drop to cause de-operation was much less now than formerly, and correspondingly the reverse series amperes (with the battery connected) were now reduced to 1.1. Likewise in the hot condition, (not, however, so hot as previously, owing to the lesser heating). The shunt current at de-operation was also less than that immediately after operation by a smaller amount than previously, but greater than for the cold condition, and the reverse series amperes were now 1.5. The above results indicate that the series reverse current cannot be eliminated by this means, as they claim. Taking the cut-out in its original condition, its operation lies within the limits given in our specification of electrical operation of cut-out for R.R. car, except that the reverse series amperes are greater both hot and cold than the limits we have assigned. With the additional resistance inserted the operation fell only entirely within our limits. Contd. | ||