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).
Continued description of a charging system, detailing the function and connection of a voltmeter.
| Identifier | WestWitteringFiles\R\2October1927-November-1927\ 42 | |
| Date | 18th April 1925 guessed | |
| -3- Contd. the boundaries of these two units being marked round respectively with green and red pencil. This diagram has been made to include each type of suggestion for the better control of the charging of the system, viz. (1) Voltmeter. (2) Danger lamp unit as referred to above. (3) Auto switch unit, but any two of these three units can be imagined deleted from the diagram when the third is under consideration. We will take the consideration of these three in the order as above, and in each case it will be noted that there is a good deal to consider in the exact way these various units may be connected. The connections as shown for the three units are those which we have arrived at after careful consideration as being generally the best. (1) Voltmeter. (Needing two units of human element), This is connected as shown between the main switch side of the field fuse and earth. It will read almost exactly the voltage of the system available at the switchbox when charging is taking place. When the dynamo is not running, it will read the battery voltage when the main switch is put on. It will do this even if the field fuse has been removed or melted from any cause. It is a very small load on the system when the main switch is put on, but this is of no consequence because it is only in the same street as the ignition load in this respect (if the ignition contact points Contd. | ||