Comparison table of technical specifications for four different starter motors for small cars.
| Identifier | ExFiles\Box 61b\3\ scan0194 | |
| Date | 21th June 1927 guessed | |
| X 543. STARTER MOTOR TABLES II. Motors for small car MOTOR x4342x C.A.V. S.C. x4342x SMITH S.S. x4384 R.R. GOSHAWK(Aero Engine)(Codename for 20HP Car / Aero Engine after Kestrel(Aero Engine)) x434PL Lucas 4880 WEIGHTS IN LBS COMPLETE MACHINE WITHOUT PINION SPROCKET OR SUSPENSION: 20.0, 16.4, 17.1, 17.5 ARMATURE COMPLETE WITHOUT PINION OR SPROCKET.: 8.6 WITH END-PLATE, 6.3 WITH END-PLATE, 8.1 WITH END-PLATE, 8.5 WITH END-PLATE BARE WEIGHT OF CARCASE AND POLE PIECES.: —, —, —, — WEIGHT OF ARMATURE STAMPINGS.: —, —, —, — WEIGHT OF ARMATURE COPPER [EXCLUSIVE OF COMMUTATOR]: —, —, —, — WEIGHT OF FIELD COPPER: —, —, —, — AIR GAP Mm.: .69, .95, .38, .38 INCHES: .027, .035, .015, .015 FIELD CIRCUIT NUMBER OF WOUND POLES.: 4, 4, 4, 4 CONDUCTOR DIMENSIONS [INCHES]: —, —, 4 wires per strip .15" x .05" bare, — NUMBER OF TURNS PER COIL.: —, —, 5.5, — ARRANGEMENT OF COILS.: 2 SERIES 2 PARALLEL, ALL IN SERIES, ALL IN SERIES, ALL IN SERIES RESISTANCE OF FIELD CIRCUIT. OHMS [COLD 18°C]: .0070, .0213, .0064 20°C, .0088 ARMATURE CIRCUIT TYPE OF WINDING.: RET. WAVE, RET. WAVE, RET. WAVE, PROG LAP NO OF SLOTS.: 25, 13, 29, 29 NO OF CONDUCTORS.: —, —, 116, — CONDUCTORS PER SLOT.: —, —, 4, — COILS PER SLOT.: 1, 1, 1, 1 NO OF COILS OR COMMUTATOR BARS.: 25, 13, 29, 29 TURNS PER COIL.: —, —, 2, — VIRTUAL CONDUCTORS.: 50, 26, 58, 58 WINDING PITCH IN VIRTUAL CONDUCTORS: 13 & 11, 7 & 5, 15 & 13, FOR. 13 BACK. 11 STEP OR WINDING PITCH IN SLOTS.: (1 & 7), (1 & 4), (1 & 8), (1 & 7) ARMATURE RESISTANCE OHMS [COLD 18°C]: .0125, .0180 23°C, .0205 20°C, .0098 CONDUCTOR DIMENSIONS [INCHES].: —, —, .080" 14 S.W.G., — COMMUTATOR and BRUSHES COMMUTATOR DIAMETER.: 1.62, 1.50", 1.825, 1.375 COMMUTATOR LENGTH.: 1.13, .90", .95, .70 BRUSH CONTACT AREA.: 2x .875" x .28" .490□", 2x .75" x .375" = .281□", 2x .75" x .31" = .465□", 2x .50 x .30 = .300□" GRADE AND HARDNESS OF BRUSHES: MORGANITE C.M.3., MORGANITE C.M.3., MORGANITE C.M.3, MORGANITE C.M.3 ARRANGEMENT OF BRUSHES.: 4 AT. 90°, 2 AT 90°, 4 AT. 90°, 4 AT 90° RATIO OF FIELD RESISTANCE TO ARMATURE RESISTANCE: .560, 1.180, .312, .898 | ||
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).