【4-in-1 Multimeter】 This digital DC voltmeter ammeter measures voltage, current, energy, and active power of electrical appliances. CCC, FCC, and CE certified. 【Measurement Range】 Voltage test range: DC 6.5~100V; current test range: 0~20A; active power test range: 0~2kW; energy test range: 0~9999kWh. DO NOT exceed the rated parameters. 20A is for short loads only, not continuous operation. We recommend upgrading to the 50A version if using with continuous output over 15A. 【More Features】 Large LCD display with backlight; voltage alarm function; energy reset function; data storage in case of power failure; built-in shunt, no need for an external shunt. 【Wide Application】 This DC voltmeter is suitable for indoor use and cannot be used outdoors. It can be used to monitor volts, amps, power, and energy consumption of batteries, solar systems, electric bicycle generators, and other applications. The load must not exceed the rated voltage and current. 【Package】 Includes: 1*DC multimeter, 1*user manual. Please note: Connect according to the wiring diagram we provide. If you want to try a different connection, contact us first, as incorrect connections can cause the product to burn out or malfunction. Measures electrical parameters (voltage, current, active power, energy). Voltage alarm function (over-voltage alarm threshold, backlight and voltage flashing when alarming). Energy key reset function. Stores data in case of power failure. Large LCD screen (displays voltage, current, active power, and energy simultaneously). Backlight function. Backlight control: Press the button to turn the backlight on or off. The backlight status is saved in case of power failure. Reset energy: Hold the button for 5 seconds until the digit flashes, then release the button. Press the button again to clear the energy value and exit the reset flashing mode. If you don't want to clear, hold the button for 5 seconds until the digit stops flashing, meaning the energy value is not cleared and you exit the reset mode. Voltage: Hold the button until the current imaging area shows SET, release the button. The voltage area shows the current high voltage alarm value, the current area shows the current low voltage alarm value, and the last digit starts flashing. Press the button to adjust the value. It automatically changes the digit without operation for 3 seconds, then press the button to adjust the value as well. Voltage alarm limit setting range: 6.5V to 99.9V. After completing the settings, hold the button until the display shows PASS. Wiring diagram Precautions: This module is suitable for indoor use, do not use it outdoors. The applied load must not exceed the rated voltage and current. The wiring sequence must not be incorrect.