The KL-F series volt-ampere meter is a new type of coulomb meter that can measure various physical parameters such as voltage, current, power, charge and discharge capacity, watt-hours, and time. At the same time, it can also set parameters to achieve over-voltage protection, under-voltage protection, Multiple protection functions such as over current protection, over power protection, and over temperature protection. The meter can automatically identify the direction of the current, and can monitor the battery capacity in real time.