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).
Serious fault in a thermometer with an earthed terminal, proposing testing of all stock and the addition of protective covers.
| Identifier | ExFiles\Box 175\4\ img080 | |
| Date | 31th August 1927 | |
| X3875 To BY.{R.W. Bailey - Chief Engineer} from EFC. c. BY/HEB.{H. Biraben} EFC2/T31.8.27. We have handed to Mr. Booth a thermometer with electrical contact which is unsatisfactory in that one of the terminals is earthed to the case. This item having been standardised, we have placed the matter in your hands to be taken up with the makers. This is rather a serious fault so far as we are concerned, on account of its relation to the remainder of the electrical system. The question naturally arises as to whether any other thermometers that we have in stock suffer from the same fault, and we suggest that careful inspection and electrical test be made. The electrical test should consist of testing separately the insulation of the two terminals (thermometer cold) utilising a 12-volt battery and voltmeter of 15 volt range. There should be no movement of the needle as between either terminal and the case. As mentioned to BY/RD recently, we are of the opinion that there should be a small cover over these thermometer terminals, also over the insulated terminal of the indicating lamp to prevent accidents due to an earthed conductor coming in contact with these terminals. We already have a cover over the ammeter terminals. EFC. | ||