Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Erratic performance and testing of a voltage regulator with various battery conditions.

Identifier  WestWitteringFiles\E\July1920\  Scan29
Date  22th July 1920
  
R.R. 199 (250T) (SD676 19-7-17) MP180865

Contd. -5- EFC1/T22.7.20.

taken from 49-GB and issued under cover of our EFC5/T22.1.18, together with other curves showing alround satisfactory operation). The voltage appears to drop, at one point, below 11 and to rise again and be maintained at speeds over 1800 R.P.M. to a value in the neighbourhood of 12.7. The curve is very similar with the machine in a hot condition with the exception that the cut-in operates and the vibrator regulator begins to operate at somewhat higher voltages and speeds. As would be expected from this open circuit volt curve, the ampere output speed curves, when operating on a normally charged 12 volt battery, are very erratic. After the instant of cutting in, there is a reverse current of 4.4 amperes; this is gradually reduced to zero and increased to a positive value of 7.4, after which the vibrator begins to operate and the current falls again and attains a negative value of 2 amperes. After this again the current becomes positive and remains positive at a value of approximately 1 ampere for speeds above 1600 R.P.M. corresponding exactly with the volt curve already described.

It is obvious from the above that something is wrong with this regulator. When allowed to operate on an 8 volt battery the operation is more reasonable, except for the fact that there is too little difference between the - charging current given to an 8 volt battery fully discharged, (e.g. a 6 volt battery) and one fully charged, which rather

Contd.
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙