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 from Weston Electrical Instrument Co. regarding the supply of a Model 301 ammeter.
| Identifier | ExFiles\Box 33\4\ Scan164 | |
| Date | 4th April 1919 | |
| X.1782. WESTON ELECTRICAL INSTRUMENT CO., AUDREY HOUSE, ELY PLACE, HOLBORN, LONDON, E.C.1. 4th April, 1919. Messrs. Rolls-Royce Ltd., Nightingale Road, Derby. Ammeter for Chassis X.1162 ^ X.1782. Ref: EFCa/T. Dear Sirs, We are obliged by yours of the 2nd. inst., and we are arranging to send you a Model 301 ammeter reading 30-0-30 amps, with white markings upon a black scale. We may possibly get this off to you to-day, but if not we will despatch it to-morrow so that you should receive it on the 7th inst. We regret that we are not able to complete a range 20-0-20 as promptly as this, and trust the sample we are sending will prove sufficient for your present requirements. You could safely overload a 20 amp. instrument up to 30 amps. without damaging it. We are confident that you will be very pleased with the behaviour of these small instruments, and they represent the finest production that has ever been incorporated in instruments of this type, in fact they may be truthfully regarded as "Electrical Measuring Instruments" instead of merely indicators, which is the type that is usually placed upon cars. We think you will agree that it seems ridiculous to place a very cheap indicator upon an expensive car, where considerable damage may arise through the indicator being unreliable. With our instrument it is possible to take a reading of the instrument when the car is travelling at any speed and under the worst conditions, because the reading of the instrument is a function of the electrical circuit only, and is not affected by the vibration of the car. If a voltmeter | ||