Everett Edgcumbe Electrostatic Kilovolt meter

Serial number 748442

This meter was in a very grubby condition when I purchased it on Ebay recently for 3.70. I was intrigued by the fact that it was calibrated in peak volts and apparently had three ranges.

View of the interior. The inside of the box has been painted with gold coloured metallic paint. The pointer can be clamped by rotating a screw on the left hand side of the box. Connections to the meter movement are by two supporting pillars one of which passes through a substantial porcelain insulator to the rear of the instrument. I have cleaned it up, replaced a loose screw and tightened others. To do this I needed to remove the scale and discovered the markings on the rear pictured below. The scale was rather dirty and after gently washing and drying it was apparent the sheen that the original numeral markings had been erased.

This view of the back of the meter scale shows the instructions for the scale to be altered sometime after initial manufacture. If you have an idea as to why this might have been done please let me know.

This is a close up view of the meter movement. The aluminium vane is attracted towards the left where it finds a stable position depending upon the applied voltage between two fixed vanes

Does it work? The only ready source of high voltage to hand was my mystery induction coil induction.html which when energised with a rather dead 12volt battery produced a reading of 11 on the 20 kV scale which I assume corresponds to about 2.8 kV.