This Voltmeter Unit is a voltage meter that can monitor the voltage in real time. The 16-bit ADC (analog-to-digital) converter ADS1115 is used internally to communicate through I2C (0X49). In order to ensure the measurement accuracy, there is a built-in DC-DC isolated power supply, and the I2C interface is also electrically isolated through the low-power isolator CA-IS3020S. This prevents noise and surges on the data bus or other circuits from entering the local ground terminal to interfere or damage sensitive circuits. Each unit is individually calibrated when leaving the factory, with an initial accuracy of 0.1%FS, ±1 count, and a maximum measurement voltage of ±36V. The EEPROM (0x53) has built-in calibration parameters when leaving the factory. Please DO NOT write to the EEPROM, otherwise the calibration data will be overwritten and the measurement results will be inaccurate. Features * ±36V range * LED power indicator * 16-bit ADC conversion * Resolution: Auto range, Count ≤ 16V, 1mV; Count > 16V, 7.9mV * Inital accuracy 0.1%FS, ±1 count * Built-in CA-IS3020S isolation chip, anti-interference * Isolated DC-DC * Up to 1000 VRMS isolation withstand voltage * Development platform: Arduino, UIFlow (under development) * 2x LEGO compatible holes Package Contents * 1x Voltmeter Unit * 1x Grove Cable (20cm) Specifications Resources Parameter Resolution Auto range, Count ≤ 16V, 1mV; Count > 16V, 7.9mV Measuring range ±36V Inital Accurancy 0.1%FS, ±1 count Communication protocol I2C: 0x49 Net Weight 9g Gross Weight 24g Product Size 65 x 24 x 8mm Package Size 67 x 53 x 12mm Resources * Documents https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2023-03-07 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2023-07-15 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2023-12-27 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2024-09-19 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2024-11-29 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2024-11-30 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2025-04-29 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2025-08-05 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2025-11-28 https://elecena.pl/product/22723870/m5stack-voltmeter-unit-ads1115 2025-11-29