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).
Temperature test of six paper condensers to ascertain their behaviour at various temperatures up to 80°C.
| Identifier | ExFiles\Box 52\3\ Scan105 | |
| Date | 7th July 1923 | |
| COPY EFC. {E. Fowler Clarke - Electrical Engineer} PB.104. July 7th. 1923. TEMPERATURE TEST OF PAPER CONDENSERS. Six paper condensers, five R.R., and one U.S.A. Bosch have been subjected to a heat test with a view to ascertaining their behaviours at various temperatures up to 80°C. It was known that long before the condenser reached that temp., leakage would commence, and that the capacity values obtained at the higher temperatures would only be apparent capacities. Nevertheless it was decided to take them up to 80°C as it was thought that a condenser might, in exceptional circumstances, attain that temperature on the car. The condensers were tested in two groups of three each made up as follows. Group A. {Mr Adams} 1. Goshawk condenser No.494 with improved connextions. 2. Std. Goshawk condenser No.524. 3. U.S.A.Bosch (Marked 774). Group B. 4. Expl. condenser No.613 baked at a higher temperature. 5. Goshawk condenser No.32 below std. in capacity. 6. Std. Goshawk condenser No.547. As it was necessary that the temperature should be raised and lowered slowly, and therefore impossible to complete a cycle of temperature in one day, the temperature had at times, to be raised to the point at which it was left the previous day. These intermediate heatings up were not fully taken account of in testing the first group, so that only the two main curves were obtained, i.e. with temperature rising and falling. In the second group, however, readings were taken resulting in a set of subsidiary curves, which with the main curves shew how many times the condensers were heated up, the temperatures passed through each time, and the increase in capacity with each cycle. It will be seen from the curves (second group) that each condenser has acquired a permanent increase in capacity This increase is about 40% of its initial value and appears to depend in amount on the temperature to which it is raised above a certain point (apparently about 50°C) and the number of times it is raised above that point. Actually the increases are as follows :- Contd. | ||