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).
Instructions for the first charge of a battery, including a density conversion table for the electrolyte.
| Identifier | ExFiles\Box 26\2\ Scan155 | |
| Date | 1st August 1919 guessed | |
| -5- channel. In replacing the stoppers care should be taken on all batteries that these are well turned after insertion to seal the joint and prevent escape of acid. At the same time communication between the air space at the top of the battery and the vent itself is effected. On any batteries fitted with such loose rings, it is therefore desirable, when these stoppers are removed for charging, to return these rings through the 90º during the charging process. During this first charge watch the acid density in each cell, using a syringe-hydrometer and do not allow it to exceed 1290. If it does, withdraw some acid and replace with distilled water, allowing time for mixing. Ordinarily the acid in the hydrometer must be allowed to return to the cell from which it was drawn. In order to facilitate the use of a hydrometer when determining the density of the electrolyte, we list below the principal readings required. Density or Specific Gravity. Twaddles hydrometer degrees Baume degrees. (approx). 1150 30 19 1200 40 24 1225 45 27 1270 54 31 1280 56 31.5 1290 58 32 1350 70 37 1835 167 66 The first charge should not be considered complete until the densities have remained constant for five hours. Contd. | ||