Good morning everyone,

My multimeter does not support measuring AC current and the frequency of AC so I designed this cirquit to measure these values for the door bell of my house which is almost 13.5 V AC (and I am not sure if this is RMS since my multimeter does not provide enough info). I am not experienced at all using Mains in my cirquits so I would like to ask is connecting the neutral of mains and the ground of WeMos D1 Mini

Edit: In Greece we have 220V AC

Edit 2: If you are wondering about the resistor at right it is not needed but it is there because of the rules of EasyEDA which requires the 5V Vcc to be connected at least to two nets.

My multimeter does not support measuring AC current and the frequency of AC so I designed this cirquit to measure these values for the door bell of my house which is almost 13.5 V AC (and I am not sure if this is RMS since my multimeter does not provide enough info). I am not experienced at all using Mains in my cirquits so I would like to ask is connecting the neutral of mains and the ground of WeMos D1 Mini

**wrong**or**is it ok?**In the connector, 1 is neutral and 2 is the line. Then I decided to use also a variable voltage divider to try it to measure bigger voltages as the voltage comparator LM311 supports a V(IN)+ up to 15V so its output can be used to measure the frequency. The question is the same:**Ok or Not?**The same is valid for measuring the Voltage and the intension I of current of mains with the other varialbe voltage divider (**Ok or Not?)**. Radial potensiometers RP1, RP3 are 500k and RP2 is 100k. Here is the cirquit. Obviously the whole cirquit will me insulated when in use.Edit: In Greece we have 220V AC

Edit 2: If you are wondering about the resistor at right it is not needed but it is there because of the rules of EasyEDA which requires the 5V Vcc to be connected at least to two nets.

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