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 log for commutators, detailing results of baking, insulation, and material tests.
| Identifier | ExFiles\Box 50\5\ Scan132 | |
| Date | 22th March 1922 | |
| The main body of the document is a mirrored image, the text below is the decoded (flipped) version. Overlaid Note (not mirrored): * In this case the commutator was baked for 24 hours at 140° C. previous to being handed over for test. Faint Mirrored Text Under Note (decoded): (It is being understood that this I.M.S. part remained O.K. to continue the test after which the figures given for the test after the bake, the second column shows the test record, see letter) Table Headers: Date of Test | Moulding Material: For | Test Speed or Voltage | Duration Test | Result | Insulation Resistance Table Content: Row 1: Date: 22.3.22 Material: 1. Asbestos .013" d, 2. Plainte c. Notes: Baked. Moulded core not re-trued. no saw cut. single splines checked long.. Test Speed: 3000 Duration: 3 min Result: O.K. Resistance: 100 ∞, 100 ∞ Ref: SS. {S. Smith} 3.22 Row 2: Date: 27.3.22 Material: 1. Asbestos .013" d, 2. Mouldensite b. Notes: 2 Segs. only. from two. Test Speed: 3000 Duration: 3 min Result: O.K. Resistance: 28 ∞, 28 ∞ Ref: SS. {S. Smith} 3.27 Row 3: Date: 27.3.22 Material: 1. Asbestos .013" d, 2. Mouldensite e. {Mr Elliott - Chief Engineer} Notes: Ditto (condn). No flux. Test Speed: 3000 Duration: 3 min Result: O.K. Resistance: 28 ∞, 28 ∞ Ref: SS. {S. Smith} 3.27 Row 4: Date: 28.3.22 Material: 1. Ditto (Condn) d, 2. Ditto e. {Mr Elliott - Chief Engineer} Notes: 2 Segs. well filled. Out. Test Speed: 3000 Duration: 3 min Result: O.K. Resistance: 106 ∞, 106 ∞ Ref: SS. {S. Smith} 3.28 Row 5: Date: 28.3.22 Material: 1. Asbestos .013" d, 2. Bakelite f. {Mr Friese} Notes: Only moulded between segments. Odd spaces not filled. OSSO obtained. Test Speed: 3000 Duration: 3 min Result: O.K. Resistance: 102 ∞, 102 ∞ Ref: SS. {S. Smith} 3.28 Row 6: Date: 29.3.22 Material: 1. Mouldensite d, 2. Plain .013" e. {Mr Elliott - Chief Engineer} Notes: Baked. Moulded core not re-trued. single. Test Speed: 3000 Duration: 3 min Result: O.K. Resistance: 100 ∞, 110 ∞ Ref: SS. {S. Smith} 3.29 | ||