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).
Standardisation sheets for new battery and starter motor options, including a comparison of Exide and P & R batteries.
| Identifier | ExFiles\Box 38\5\ Scan214 | |
| Date | 4th April 1922 | |
| To Hs{Lord Ernest Hives - Chair} (at Le CanadelHenry Royce's French residence). from EFC. Handwritten top center: X3398 We are about to send round the standardisation sheets for the following items :- 1. Larger battery - for this it is proposed to have two simultaneous standards. Handwritten left margin: X4186 (a) New larger Exide type 6XN5. X3398 (struck through) (b) P & R battery type B.D.11. Handwritten left margin: X4399 2. Starter motor with field coils arrgd. two series two parallel, together with starter motor cables of increased section of conducting core, viz. 133/25 instead of 84/25. Handwritten left margin: X4132 3. R.R. standard starter motor (with field coils two series twoparallel) built up with solid poles and no insulation other than oxide (or varnish if bright plates) between the armature plates. We have one of the larger Exide batteries running on the School car, and as you know, one of the P & R's has been running on 1 EX for a considerable time with satisfactory results. The rated ampere hour capacity of the two batteries is the same, viz. 75. We find on the bench that the Exide battery gives more ampere-hours and also has a bigger high rate discharge curve, showing better cranking ability. It weighs 104 lbs. whereas the P & R weighs 95lbs. The Exide price is £7. 5. 0. The most recently quoted P & R price is particularly low, £4. 7. 6., including teak case, and we do not understand how it can pay them at this price. They have also quoted £4. 17. 6 for the same battery with case to be dropped into our own battery box in the same manner as at present. For your information we send you copies of the standardisation sheets we shall be sending round. | ||