Tabular report on performance and noise level tests for various speed ranges.
| Identifier | ExFiles\Box 4\5\ 05-page347 | |
| Date | 2nd September 1924 guessed | |
| -la {L. A. Archer} - (11a) Speed range: R.P.M. (12) Speed R.P.M. (13) Lowest speeds for 5.5 mm. gaps (R.P.M.) (Sub-headings: Adv., Central, Retard.) (14) Secondary m.a. on 108 Volts 30~ (Sub-headings: Max., Min.) (15) (6) Remarks re silence. Row 1: Speed range: (3 mm leak) (3.5 mm gap) 700 to 3500 Speed R.P.M.: 3500 Lowest speeds: Adv. 250, Central 190, Retard. 160 Secondary m.a.: Max. 9.3, Min. 8.0 (15): Variation 3º Remarks: Rather noisy machine. Row 2: Speed range: (3 leak) (3.0 mm gap) 490 to 1620 Speed R.P.M.: 2650 Lowest speeds: Adv. 280, Central 230, Retard. 210 Secondary m.a.: Max. 17.1, Min. 11.0 (15): Variation 2º Remarks: Reasonably quiet - fitted with bakelite gear pinion & duralumin contact breaker lever. Row 3: Speed range: (3 leak. 3.0 mm. gap). 1020 to 2800 Speed R.P.M.: 4400 Lowest speeds: Adv. 280, Central 240, Retard. 270 Secondary m.a.: Max. 9.0, Min. 4.8 (15): Variation 1º Remarks: Rather noisy machine - particularly make & break. Row 4: Speed range: 360 - 2200 retarded ? central Speed R.P.M.: 3100 Lowest speeds: Adv. 185, Central 145, Retard. 125 Secondary m.a.: Max. 19.3, Min. 9.6 (15): O.K. Remarks: Slight gear and sleeve noises. Row 5: Speed range: 320 - 3300 Speed R.P.M.: 4500 Lowest speeds: Adv. 215, Central 170, Retard. 170 Secondary m.a.: Max. 17.4, Min. 6.5 (15): O.K. 2º Remarks: Very quiet machine in spite of being a sleeve magneto. Row 6: Speed range: 350 - 3700 Speed R.P.M.: 4500 Lowest speeds: Adv. 200, Central 170, Retard. 160 Secondary m.a.: Max. 19.2, Min. 7.0 (15): O.K. 2º Remarks: Quiet machine as above. Row 7: Speed range: 500 - 3000 Speed R.P.M.: 3450 Lowest speeds: Adv. 210, Central 160, Retard. 160 Secondary m.a.: Max. 17.1, Min. 10.0 (15): O.K. 2º Remarks: Sleeve noise reduced. Noisy gears and bearing hum. Noisy contact breaker. | ||
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).