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).
Tests comparing a standard and an experimental starter motor cable to reduce volt drop.
| Identifier | ExFiles\Box 62\1\ scan0176 | |
| Date | 19th October 1933 | |
| x6134 E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to By/RD. Hs{Lord Ernest Hives - Chair}/Wst.5/MA.19.10.33. COLD STARTING. REDUCTION IN STARTER x 6001. MOTOR CABLE VOLT DROP. We have now carried out tests on the sample length of starter motor cable of increased section as referred to in By/RD.5/W.27.9.33. The resistance of the cable was carefully measured, and the temperature rise, increase of resistance and volt-drop measured after passing a current of 300 amperes for 2 mins. We give below a table shewing the results of these tests compared with similar tests on the existing standard starter cable. Cable. Resistance. Resistance. Temperature Volt drop in ohms per per foot rise after per foot foot (cold) carrying 2 mins. carrying 300 amperes. carrying 300 amperes. 300 amperes. Std. Cable .000347 .000436 59°C. .131 volts Expl. .0001465 .0001572 19°C. .047 volts Cable. (61/.036) It will be seen that this cable compares very favourably with our standard cable, the temperature rise and volt drop being a third of that obtained with the standard cable. | ||