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).
The endurance testing of a sequence starter main switch and the performance of its copper laminated contact brush.
| Identifier | WestWitteringFiles\V\December1930-February1931\ Scan030 | |
| Date | 6th December 1930 | |
| To R.{Sir Henry Royce} from EFC. c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} c. E.{Mr Elliott - Chief Engineer} Ry. ORIGINAL EFC5/ADL6.12.30. X.7655. SEQUENCE STARTER MAIN SWITCH TO LeC.2804. Further to our EFC3/AD2.12.30. the endurance test therein mentioned has now been completed, the copper laminated contact brush in this case being as called for on the drawing i.e. with the thin gauge copper. In this connection my assistant's report WE.66, reads as follows :- "The switch was fitted to our sequence starter crankshaft test rig and 20,000 starts were made automatically, the main average current being 160 amperes, the main switch coil being operated at about a 10% above normal voltage i.e. 13.0 volts. No failure or unsatisfactory operation of the main switch was experienced throughout the test. Upon observing the switch under operating conditions it was seen that the carbons were making first and taking most of the sparking. The condition of the copper contacts confirmed this as upon examination at the conclusion of the test it was noticed that very little burning or marking had occurred, being much less than that experienced with a similar test we carried out on a standard switch. With the thicker gauge copper laminated contact brush which ex-isted we have asked for and which is fitted to the switch on 27-EX, therefore, the contact condition should be still further improved." EFC. | ||