A moving coil permanent magnet ammeter provides the basis for this.
Todays average clamp-on ammeter is not accurate enough at such a small scale.
The current is amplified and displayed on an ammeter.
Measuring instruments such as ammeters and voltmeters need to be checked periodically against known standards.
It started with electronics testing equipment such as power meters and ohmmeters, and followed later by ammeters.
This type of meter responds to both direct and alternating currents (as opposed to the moving-coil ammeter, which works on direct current only).
Zero-center ammeters are also commonly placed in series with a battery.
The plant opened in 1941, and employed up to 279 people making ammeters, gauges, and instrument clusters.
