Product Description The ZMPT101B AC Voltage Sensor Module is a sophisticated sensor designed for measuring AC voltage with high accuracy and safety. Unlike simple resistive dividers, this module uses a built-in high-precision micro-voltage transformer to provide galvanic isolation between the high-voltage AC side and the low-voltage DC side. This ensures that your microcontroller (like Arduino, ESP32, or STM32) remains safe from high-voltage spikes. It converts the 230V AC mains signal into a small analog sine wave that can be sampled by any ADC. It is the gold standard at Robogears for building DIY energy meters, smart home voltage monitors, and industrial power quality analyzers.
Key Highlights
Safe Isolation: Features a micro-voltage transformer that provides up to 4000V of isolation, keeping your logic circuits physically separated from the mains power.
Analog Sine Wave Output: The output is an analog wave shifted by an offset (typically VCC/2), allowing the microcontroller to capture the full AC waveform for RMS calculations.
Onboard Calibration: Equipped with a multi-turn trimmer potentiometer to adjust the output gain, ensuring the sensor can be calibrated to match the specific AC voltage range being measured.
High Precision: The ZMPT101B series is known for its linear output and excellent consistency across a wide temperature range.
Compact Integration: The small PCB footprint includes both the transformer and the necessary amplification circuitry (LM358), making it a "plug-and-play" solution for power monitoring.
Technical Specifications
Secondary Current: < 2mA
Linearity: 0.1%
Phase Error: < 20' (at 50Hz)
Operating Temperature: -40°C to +70°C
Dimensions: 49.5mm x 19.4mm
Weight: ~20 Grams
Installation Tip from Robogears Since the output is an AC sine wave centered around an offset, you cannot simply use a single analogRead() to get the voltage. You must sample the wave multiple times over at least one full cycle (20ms for 50Hz) and calculate the Root Mean Square (RMS) value in your code. Safety Warning: The input side carries lethal mains voltage (230V AC). Always ensure the module is placed in a non-conductive enclosure and never touch the high-voltage terminals while the device is powered.
Note: This product is the sensor module ONLY. Connection wires and enclosures are sold separately. Product images are for illustration purposes only.
