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 electrical properties and performance of a Delco Coil No. 2178.
| Identifier | WestWitteringFiles\N\2October1925-December1925\ Scan115 | |
| Date | 2nd November 1925 | |
| COPY. EFC/ WB.{Mr Brazier/Mr Bell}57. Nov. 2nd. 1925. DELCO COIL. No. 2178. This coil is unconventional to usual practice in the respect that it has a nearly closed iron core circuit. The windings, which are arranged electrically as diagram below, are enclosed in a black moulded case. [Winding Diagram showing a primary coil 'P' and a secondary coil 'S' with H.T. output] WINDING DIAGRAM. - - - - - - - - - - - - The resistance, impedance (50~) and inductances of the windings are as follows :- Primary winding. Resistance 16°C : .662 ohms. Impedance : 2.75 " Inductance : .0084 henry. Secondary winding. Resistance 16°C : 2705 ohms. Impedance : 9320 " Inductance : 28.0 henries. When run in conjunction with our standard distributor at 700 r.p.m. (make ratio .5) the coil successfully underwent an open circuit test at 12 volts for 5 mins. the running current being 1.38 amperes. Also the coil functioned perfectly at 8 volts, no missing being observed on 6.5 mm. gaps, the running current at 8 volts being 1.05 amps. EFC/H.West. | ||