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).
Letter from accumulator manufacturers Peto & Radford regarding observations on acid gravity during battery charging.
| Identifier | ExFiles\Box 38\5\ Scan190 | |
| Date | 9th December 1921 | |
| X 3398 Works, Dagenham Dock, Essex and Ashtead, Surrey TELEPHONE VICTORIA 3667. 4-LINES PRIVATE BRANCH EXCHANGE. TELEGRAMS CONCENTRATION, SOWEST, LONDON. Manufacturers of P&R Accumulators. Established 1889 PETO & RADFORD Proprietors - Pritchett & Gold and E.P.S. Company Ltd. 50 GROSVENOR GARDENS, LONDON, S.W.1. DIRECTORS: SIR ARCHIBALD G.GOLD F.C.GRAHAM MENZIES C.R.D.PRITCHETT G.R.N.MINCHIN T.W. PRITCHETT WILLIAM PETO DAVID WILLOCK. YOUR REF. OUR REF. H/C.912. 9th Dec. 1921 Messrs. Rolls Royce Ltd., NIGHTINGALE ROAD, DERBY. [STAMP: RECEIVED 10 DEC 1921] Dear Sirs, For the attention of Mr. Fowler-Clark. Further to our recent letter on the subject of acid gravity during charging, we have had our statement verified through our laboratory, namely that the acid will be at a higher gravity at the end of the charge. If it is at a lower one, it would appear that the battery is not yet fully charged as charging should continue until the acid gravity ceases to rise. As a matter of fact, we found that the curve falls and then comes up again, i.e. if acid is put in at 12.20 to 12.50, in the early part of the charge it will be found to be below 12.00 and then gradually rise to about 12.80 to 13.00. We thought you would like to have these further observations, and remain, Yours faithfully, PETO & RADFORD G.R.N.Minchin | ||