Active Single Phase Voltage Sensor Transformer Module AC Output ZMPT101B

SKU	ELE-COM-122
Ships from	Cardiff, UK

The ZMPT101B voltage sensor module is an isolated AC mains voltage sensor for Arduino, ESP32 and Raspberry Pi projects, measuring up to 250 V AC.

The board pairs a precision micro voltage transformer with an on-board op-amp circuit. As a result, the live AC waveform is scaled down and biased into a safe analog signal for a microcontroller. The ZMPT101B voltage sensor outputs a clean sine wave centred on a DC offset, which makes RMS calculation straightforward in software.

Key Features of the ZMPT101B Voltage Sensor

• Measures AC voltages up to 250 V (50/60 Hz)
• Galvanic isolation through an on-board voltage transformer rated to 4000 V test isolation
• Adjustable gain trim pot for calibrating the output amplitude
• Sine-wave analog output with a DC bias for single-supply ADCs
• Wide 5–30 V supply range
• Compact 3-pin output: VCC, GND, signal

Use Cases

• Building an Arduino or ESP32 mains energy meter with RMS voltage display
• Logging mains voltage over time to spot brownouts or sags
• Combining with an ACS712 current sensor to compute real power and power factor
• Adding mains-voltage monitoring to a home automation dashboard
• Triggering alerts when voltage drifts outside a safe band for sensitive equipment

Works Well With

• Arduino UNO R3 WiFi Board (ESP8266 + ATmega328P) — gives you both an analog input for the sensor and Wi-Fi to publish readings to the cloud.

Project Ideas & Tutorials

• Measure AC Voltage with ZMPT101B and ESP8266 (Hackster) — wiring, calibration and a sketch that prints RMS voltage to the serial monitor.
• AC Power Meter with Power Factor (Instructables) — combines the ZMPT101B with a current sensor on an Arduino Nano to measure real power.
• AC Power Meter on ESP32 (Instructables) — porting the same idea to ESP32 with a 12-bit ADC for finer voltage resolution.
• DIY Real-Time Energy Monitoring with ESP32 (Circuit Digest) — full build with ZMPT101B, current sensor and a web dashboard.

What you will receive:

1x module

Free UK delivery

Royal Mail 48 tracked · dispatched same day on orders before 14:00.

Express — £15.98

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