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).
Specification for the production inspection and testing of a chassis ammeter.
| Identifier | ExFiles\Box 168\5\ img173 | |
| Date | 3rd January 1930 | |
| X4622 3.1.30. X 4622 X 3498 CHASSIS AMMETER. SPECIFICATION OF PRODUCTION INSPECTION & TEST. (1) The instrument should be tested by means of a twelve volt battery and sensitive voltmeter to ensure that the electric circuit through the instrument is insulated from the case. (2) Having duly set the zero if necessary, check the accuracy of the instrument at one reading between ten and fifteen amperes on each side of the scale against a reasonably accurate box type instrument, and note if there is any tendency to sticking of the indicating needle at any point of the scale. Also note if similar readings are obtained with the instrument vertical and horizontal. (3) Pass a current of 90 amperes through the instrument for three seconds in one direction and then for three seconds in the other direction, and note if this causes any apparent mechanical irregularity. (4) Re-check the instrument as in (2) to see that its calibration has remained of a similar degree of accuracy. .FC. | ||