Two-way detection of current, users who detect charge and discharge can automatically identify and detect two-way current without changing the wiring direction.Power-off memory function, after power-off, the AH number before power-off can be memorized, which is convenient for observation and measurement.The time and AH number reset function does not affect the next measurement. The AH number can be filled up without affecting direct discharge measurement. It has protection functions such as overvoltage, overcurrent, overpower, time limit and overcharge.Voltage, current, charging capacity AH number, WH number, time, power are displayed at the same time, the display information is comprehensive and clear.The current is detected by the Hall sensor, and the wire that the current passes through can be passed through the round hole of the sensor. The current can be detected in both positive and negative directions, safe and convenient.This volt-ampere meter is a new type of volt-ampere meter that can measure various physical quantities such as voltage, current, charge and discharge capacity, time, power, etc.The instrument uses color LCD to display the measured data, and the display information is comprehensive and user-friendly. This meter uses a Hall sensor to detect current, which is convenient and simple, and is very suitable for applications that need to monitor the output voltage and current, and charge and discharge the battery.Current measurement range: 0-500ADisplay resolution: 0.2AVoltage measurement range: self power supply (12-90) V external power supply (0-90) VCurrent accuracy: +/- 3% +/- 5 wordsVoltage accuracy: +/- 2% +/- 5 wordsVoltage: 0.01VCapacity: 0.01AHTime: 0.01H (1min)Measurement rate: 5 times/secOVP (over voltage protection): 0.01V-90VOPP (over power protection): 0.01W-9.99KWLOP (undervoltage protection): 0.01V-90VOCP (Over Current Protection): 0.1-100AOAH (overcharge protection): 0.01AH-9999AHOFT (overtime protection): 1min-99hour59mincolour: blackMaterial: plasticsize: 7.9x4.3x5.2cmPackage Contents:1 x Voltage and current meterOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.