Instruction sheet detailing the fault finding on a returned coil by unwinding it.
| Identifier | ExFiles\Box 69\1\ scan0218 | |
| Date | 9th July 1929 | |
| RR 228 (150 BKS.) l05 461-8 12.24) MP 306975 X8710 ROLLS-ROYCE LTD. INSTRUCTIONS. To: E7C. Date: 9-7-1929 Order No.: WD {Mr Wood / Mr Whitehead} 71 Customer's No.: X8710 Coil NO EZ85 returned faulty. This coil has been carefully unwound after a preliminary bench test which revealed the fault to be a short circuit of part of the secondary winding. We found that the first 20 layers unwound were OK but on the 21ST layer evidence could be seen of a short circuit having taken place the insulation being marked and the secondary wire seen (under a lens) through the paper. This was observed also on the next four layers unwound. Continuing unwinding little definite evidence of short circuiting was seen. Signed: (contd) This Sheet must be filed on completion of the work. | ||
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).