ZMPT101B 230 volts AC Mains Voltage Sensor ,This module is based on a high precision ZMPT101B voltage Transformer. This module makes it easy to monitor AC mains voltage upto 250 volts. This module comes with Multi-turn trim pot which can be used for adjusting the Analog output.
Using ZMPT101B  AC Voltage Sensor you can easily measure main voltage using Arduino or even Raspberry Pi (external ADC required)

Features of ZMPT101B AC voltage sensor Module

1. Voltage upto 250 volts can be measured
2. Light weight with on-board micro-precision voltage transformer
3. High precision on-board op-amp circuit 
4. Operating temperature: 40ºC ~ + 70ºC
5. Supply voltage 5 volts to 30 volts

Advantages of ZMPT101B AC voltage sensor 

1. Analog output corresponding quantity can be adjusted.
2. Pcb board size: 49.5 (mm) x19.4 (mm)
3. Good consistency, for voltage and power measurement 
4. Very efficient and accuracy

Related Links

1. Measuring AC mains Voltage using Arduino
2. Voltage Monitoring webserver using NODEMCU and ZMPT101B

Here is an alternative product with the video tutorial.
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