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).
Coil endurance test failure, identifying a short circuit in the secondary layers as the cause.
| Identifier | ExFiles\Box 69\1\ scan0252 | |
| Date | 8th December 1924 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 461-8-12 24) MP 306975 ROLLS-ROYCE LTD. INSTRUCTIONS. (2) To Order No. WD{Mr Wood/Mr Whitehead}88 (contd) Customer's No. a total of 1120 hrs running equivalent to approx '32000 miles running on a chassis. The test was terminated by the coil secondary breaking down, the breakdown, upon unwinding, being found to be due to a short circuit on the first two layers. This test shows that the primary with the extra insulation (now that we are thoroughly drying and impregnating coil primaries) appears to be OK and not liable to breakdown as was feared. The weakest place in the coils now produced is in the first secondary layers. No deleterious effect was observed due to the use of paraffin waxed paper. Signed H.E.W. This Sheet must be filed on completion of the work. | ||