Peacefair PZEM-021 Voltmeter Ammeter Wattmeter Energy meter Review

This is the review of Peacefair PZEM-021 Voltmeter Ammeter Wattmeter Energy meter that I bought from Aliexpress, have been using it for a month now and all is great. Its description and help: A. Function 1. Electrical parameter measurement function (voltage, current, active power, energy) 2. Overload alarm function (over power alarm threshold, backlight and power flashing to alarm). 3. Power alarm threshold preset function (can set power alarm threshold). 4. The reset function of energy key. 5. Store data when power off. 6. Large-screen LCD (display voltage, current, active power, energy at the same time) 7. Backlight function. B. Appearance and Key function Display interface is large-screen LCD, it can display voltage, current, power, energy parameters at the same time. 1. Power: test range: 0~4.5kW within 1KW, the display format is 0.0~999.9W; 1KW and above, the display format is 1000~4500W. 2. Energy: test range: 0~9999kWh Within 10KWh, the display format is 0~9999Wh; 10kWh and above, the display format is 10~9999kWh. 3. Voltage: test range: 80~260V Display format: 80~260V 4. Current: test range: 0~100A Display format: 0.00~100A How to do Backlight control 1. Short press the key to turn on or off the backlight, the backlight has memory function, it can store the on or off state when power off. How to Reset energy Step1: Long press the key for 5 seconds until the number in energy display window flash, then release the key. Step2: Short press the key again...