More suitable battery for the electrical units testing plant.
| Identifier | ExFiles\Box 76\2\ scan0084 | |
| Date | 5th December 1924 | |
| +682 To Wor. {Arthur Wormald - General Works Manager} from EFC. {E. Fowler Clarke - Electrical Engineer} c. Hy. {Tom Haldenby - Plant Engineer} c. SFI/Mr. Brock. Mr. Brock has asked me for my suggestions concerning a more suitable battery in connection with their testing plant for the electrical units. They have been carrying along up to the present with three old standard Exide chassis batteries, paralleled up to 12 volts, but these have recently necessitated a number of cells being changed to keep the battery going, and the whole battery is now about worn out. We recommend that instead of rearranging a similar scheme with new chassis batteries, it would now be a better proposition to provide Mr. Brock with six open type cells, and the particular ones we suggest as suitable for this purpose are :- 6 Pritchett & Gold cells, of their type FA.7 each of 150 ampere-hour capacity on the 10 hour rate. (Hy. {Tom Haldenby - Plant Engineer} please see p.3 of their pamphlet No. B.14 attached). These cells are by no means expensive. The price per cell would be approximately £2:10. but possibly a little less, so that £15. would cover the cost of the battery. Thus this would be no more expensive (first cost) than three chassis batteries at £6"12"6 each, and would certainly have a bigger life. These cells could be installed behind their switchboard, and the electrolyte being covered with a layer of oil, would give off no obnoxious gasses. It would be necessary to arrange a suitable wooden stand and have this anti-sulphuric enamelled - this would only add slightly to the cost. The charging rate of these cells is given as 18 amperes (maximum 36), thus they would cope quite easily with the simultaneous output of two dynamos on test. In order to provide against serious overcharging it is suggested that a rack, containing three Zenite vitreous enamelled resistance units, be arranged for dissipating some of the current from the terminals of the battery, with a switch for each unit. Contd. | ||
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).