Specification: Description: Black character, white background, square panel mount, analogue display. Designed to measure frequency in A.C. electrical power system. Installed on the display panel and switch panel for the control system and power distribution systems. Used widely in the electronics, automatic control system, mechanical equipments, shipbuilding, aviation, etc. The US buyers need to prepare a voltage tramsformer to make this item work successfully in your area, as the voltage here is AC 220.
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