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).
Rectifying unit for high voltage D.C. insulation testing.
| Identifier | ExFiles\Box 24\2\ Scan269 | |
| Date | 29th April 1927 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. E.{Mr Elliott - Chief Engineer} PN.{Mr Northey} c. Ba. By.Hy.{Tom Haldenby - Plant Engineer} c. Wor.{Arthur Wormald - General Works Manager} X1109 EFC1/T29.4.27. + X3573 X1109 X1589 (Struck through) RECTIFYING UNIT FOR HIGH VOLTAGE D.C. TESTING OF INSULATION. We have made up such a rectifier unit which, in conjunction with a trembler coil or H.T. transformer, takes the place for testing purposes of the now out-of-date Wimshirst machine. The rectifying unit has been made up in a box so as to be portable, and contains essentially a H.T. type U3 power rectifying valve capable of a total emission from the filament of 80 ma. and rated to stand a reverse pressure from filament to plate of 3,000 volts (filament positive), two H.T. condenser units with glass dielectric in parallel, and a six-volt battery for lighting the filament of the valve. The battery can be charged in position in the box for which purpose the dotted link switch (see diagram) is removed. The electrical diagram of the arrangement is as shewn in Fig.1, the five circles being the terminals, which are arranged on an ebonite plate on one vertical side of the box, the top terminal constituting the input A.C. or intermittently positive impulsive voltage, the middle terminal being the output terminal for the rectified H.T. (positive) current, and the bottom terminal the datum or earthing terminal of the unit. The dotted line joining the other two terminals represents the link switch for lighting the filament; the two condenser units are represented as one in the diagram. The whole unit has an ebonite base so that wherever it is stood, the whole Contd. | ||