Sense the AC signal from mains power supply connected with I2C relay Board

Nate Pulkar

Hi, I have been working with Two-way switch concept in which I have connected the I2C relay Board module with ESP32 and another point is connected with the Main switches which are around 8 in numbers.

I need to detect Ac current form every switch and send the signal to the controller. I looking for the IC package which helps me to fulfill my requirement and I will easily detect the AC signal.

Any kind of suggestion on this will be a great help

over 6 years ago

0 Tom Hendrick over 6 years ago

TI__Guru**** 180941 points

Hi Nate,

What are you planning to do to detect this AC current? Shunt resistor? Maybe an INA configuration? What are you feeding this signal into, is it an ADC on your ESP32?

0 Nate Pulkar over 6 years ago in reply to Tom Hendrick

Prodigy 200 points

We have done it before but to monitor the battery voltage we used ADC.

Will it be the same volt for AC or not?

What is INA configuration? Are You talking about Star and Y configuration?

How can using a Shunt Resistor will solve our issue?

Okay, We can limit the current up to the lowest mark using a shunt resistor. Would we get the same thing what we are trying to get?

0 Tom Hendrick over 6 years ago in reply to Nate Pulkar

TI__Guru**** 180941 points

Hi Nate -

Hard to say for sure since there is still not much detail in what you want to achieve. You want to feed a signal from the relay board into your ESP32 right? Let's start there, what signal level can the ESP32 accept? Is it going to be an analog signal to be digitized by an ADC or something else?

0 Nate Pulkar over 6 years ago in reply to Tom Hendrick

Prodigy 200 points

Yes I am thinking to send the analog signal which is digitized by ESP32

0 Tom Hendrick over 6 years ago in reply to Nate Pulkar

TI__Guru**** 180941 points

Hi Nate,

Have a look through this eBook. There are several different schemes described here that may fit with your use case. Once you have a topology in mind, we can point you to a few devices that may be suitable.

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Sense the AC signal from mains power supply connected with I2C relay Board