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 performance of a machine fitted with Ubas steel pole forgings, detailing test results under cold and hot conditions.
Identifier | WestWitteringFiles\L\2Jan1924-March1924\ Scan72 | |
Date | 13th March 1924 | |
Contd. -4- EFC1/T13.3.24. curve for much the same temperature condition (though possibly 5° hotter), also a curve (long dashes) indicating the general specification of performance of machines for 40/50 chassis. It will be seen that the curve of performance now secured readily complies with this specification. For production purposes Ubas steel pole forgings have been adopted, and this particular B machine has been fitted with these pole pieces of similar dimensions to the M.S. ones giving the best result. A complete investigation of the output performance of the machine so fitted has been made, the results of which are as follows :- Arranged as a shunt machine, i.e. with control brush lifted and connected to the negative brush:- AS SHUNT MACHINE { (a) In the cold condition a balancing terminal P.D. of 12.4 volts is put up at 412 r.p.m. (b) In the hot (75°C) condition a balancing P.D. of 13.6 volts is put up at 472 r.p.m. (c) The ampere output performance rises sharply as the speed is increased above the balancing speeds mentioned, reaching 10 amperes in the cold condition at 600 r.p.m. and nearly 11 amperes in the hot condition at 700 r.p.m. The characteristic open circuit, <handwritten>controlled</handwritten> volt-speed performance in comparison with <handwritten>that of</handwritten> <strikethrough>of</strikethrough> one or two other <handwritten>controlled</handwritten> machines is shown on the side of curves labelled C attached, together with a table of balancing speed ranges between the cold and hot conditions. Contd. | ||