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 procedure document for a dynamo and cutout system, specifying operational limits for voltage, current and resistance.
| Identifier | ExFiles\Box 70\4\ scan0040 | |
| Date | 19th October 1926 guessed | |
| -2- Contd. until the cutout is just operated. The instant of operation will be shewn by a movement of the needle of ammeter A.{Mr Adams} The readings of the voltmeter V and ammeter B, immediately preceding this instant, shall be noted. The former shall lie between the limits 12.2 and 12.8 volts, and the latter shall not exceed .20 amperes at 12.5 volts, i.e. shunt coil resistance must exceed 62.5 ohms. If the cold operating voltage does not fall within the specified limits, a slight adjustment of the control spring of the contact lever should be made. (5) The dynamo shall now be speeded up to allow a charging current of 10 or more amperes to flow into the battery for a period of 5 minutes. No undue heating of the contact points must occur. (6) The dynamo speed shall be reduced until the ammeter A reading is zero. The connections to this ammeter shall then be reversed, after which the speed shall gradually be reduced still further until the cutout contacts fall apart. The instant of falling away will be shew-n by the drop to zero of the needle of the ammeter A.{Mr Adams} The readings of the voltmeter and ammeters immediately preceding this instant shall be noted. The reading of the ammeter A shall not exceed 2.0 amperes. EFC. | ||