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).
Letter to Joseph Lucas Ltd. detailing observations and requirements for Lucas Regulators type LR.7.T.
| Identifier | ExFiles\Box 166\2\ img081 | |
| Date | 5th April 1937 | |
| 6092. 5th April 1937. Rm{William Robotham - Chief Engineer}/Wst.1/AP. Messrs Joseph Lucas Ltd., Great King Street, BIRMINGHAM 19. For the attention of Mr.W.E.Robinson. Dear Sirs, Observations on Lucas Regulators type LR.{Mr Ellor}7.T. In accordance with your Mr.Thacker's request, we append below our observations on the latest type of regulator which Mr. C.Robinson sent to us recently. In considering the L.R.7.T. type of regulator, we have based our current requirements on the output-current performance, at 13 volts on the regulator terminals. These requirements, which are intended to serve as a guide, are as follows:- (1) The series compensating winding shall be such, that, with 13.0 volts on the regulator terminals, the regulating current taken from terminal A.1. i.e. passing through the whole of that winding, shall be about 10 amperes when cold and be maintained at that value for all speeds of the dynamo up to 6000 r.p.m., and all normal increase in the temperature of the regulator windings. (2) It is appreciated that the relationship between the shunt and series windings and the regulating current characteristics of the unit at various voltages are largely fixed by the requirements given in (1). We would however, like to add that:- with about 15.5 volts on the terminals and a current of 1.5 amperes taken from terminal A.1., the battery current taken from terminal A.{Mr Adams}, should be not more than 4.5 amperes, and remain constant under the various conditions. Applying this standard of performance to regulator No.LT.1028 (the first unit with the one extra turn on the load portion of the winding), we obtained the following results:- continued | ||