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).
Re-testing results of a 20 HP dynamo with pole modification and issues with noisy machines.
| Identifier | ExFiles\Box 165\6\ img124 | |
| Date | 17th March 1927 | |
| X5660 EFC. C.M.Brock. C.M.A. BY19/H.{Arthur M. Hanbury - Head Complaints} 17.3.27. P.6. KM. 20 HP. DYNAMO WITH POLE MODIFICATION. Referring to EFC6/T.8.3.27. I could not understand how the machine, which appeared to be so much away from the curve you required, was sent through by Mr.Brock to the Test. We therefore had the machine re-tested with the following results:- Dynamo. Volts. R.P.M. ------ ---- ----- Cold. 12.8 750 Warm (1 hr.run) 12.8 790 Hot (after 3 1/2 hrs.run) 12.8 840 Whilst you may consider the figures in question cannot be accepted by yourself against those quoted in your memo, the fact remains that we have to pass dynamos on to Test off the apparatus in Mr.Brock's Dept. and if this is open to question I think it should have your attention to show us where we are wrong, in order that we can bring our test into line with yours. The position at the moment is that we cannot guarantee any modified dynamo being materially better than the one which has been turned down, and since the modification prevents us using the machine later if you turn it down, I have decided that it is useless us modifying any further 20 HP. dynamos. Mr.Brock has appealed to me to give him some help to discover why machines are noisy. I have told him that my technical knowledge does not cover this branch, and the only remedy we have is to hand some of the machines over to your Department to see whether you can discover some palliative which can be utilised on dynamos which are noisy, to make them usable. Failing this, I am afraid I shall have to tell him that he has got the best I know how to produce, and the only other way out would be an unintelligent changing over of noisy machines in an attempt to produce from say a dozen noisy machines a few quiet ones. BY.{R.W. Bailey - Chief Engineer} | ||