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).
Specification for the electrical operation of a Blériot PHI Cut-Out (12 Volt System) for a car.
| Identifier | ExFiles\Box 48\3\ Scan229 | |
| Date | 31th March 1921 | |
| X.4215. 31.3.21. X.4215 - SPECIFICATION OF ELECTRICAL OPERATION OF BLERIOT PHI CUT-OUT FOR R.R. CAR X.1815 (12 VOLT SYSTEM). (1) With the cut-out in a cold condition but not lower in temperature than 15/18°C, full unhesitating (non-vibratory) electrical contact of the cut-out main contacts shall be produced by the application of a gradually increasing voltage lying between the limits 12.2 and 12.8 between the terminals Nos. 1 and 3 of the cut-out, No.2 terminal being disconnected. (2) The cut-out after being on load in connection with a dynamo and battery for two hours with an ambient temperature not less than 18°C, its series winding carrying not less than 10 amperes, shall likewise be similarly operated by the similar application of a gradually increasing voltage + lying between the limits 13.2 and 14.2 (3) In either case (1) or (2) above, the current to operate shall at no time exceed .20 ampere. (4) Supposing a battery to be connected in the usual manner to the dynamo and cut-out (which makes no difference until the main contacts close) and the dynamo speed to be gradually reduced after the cut-in has been effected, the reverse current through the series coil from Contd. + This voltage should preferably be a slightly unsteady voltage such as that from a dynamo. R3047 O (1K. bks.) 1.2.20. S & S. Ltd. | ||