Amp meter is a tool used to measure the amperage flowing through a wire or other conductive material. It is a very important tool when adjusting your HHO generator or Hydrogen on demand system for maximum output.
An amp meter measures the electric current in a circuit. Electric current is measured with the physical unit amperes and the amp meter gets its name from the amperes it measures. Amp meters can measure both alternating AC current and direct DC current. Amp meters are available both with analog and digital readings.