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of the key will turn the backlight on or off. The state (on or off) is saved even if the power is disconnected. РКС Компоненти - РАДІОМАГ Wiring and Safety Indoor Use Only:

The device remembers the backlight state after power-down. 🔋 Resetting Energy (Wh/kWh)

Peacefair PZEM-051 is a 4-in-1 DC digital multimeter used to monitor voltage, current, active power, and energy consumption simultaneously on a single LCD screen. It is primarily designed for indoor use in systems such as solar panels, battery banks, and RV electrical setups. РКС Компоненти - РАДІОМАГ Core Specifications Voltage Range: 6.5 ~ 100V DC. Current Range: 0 ~ 100A (requires an external 100A/75mV shunt). Power Range: Energy Range: 0 ~ 9999kWh. 1.0 grade (±1%). en.peacefair.cn Button Operation Guide