Reading Zero Values from PEVMAC2C Voltage Monitor?

Products
1

I am attempting to receive voltage readings from the PEVMAC2C voltage monitor. My set up involves using the ControlEverything I2C adapter module plugged into the pins of the board, and communicating to a BeagleBone Black through the ControlEverything I2C BeagleBone Shield, (setup shown below). The voltage monitor is supplied with 12V DC and the sensor inputs are connected to the provided 9V DC power supplies.

img1

Upon discovering that the device is connected at I2C bus 2 address 0x2a, I found that there are no readings captured inside this bus:

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img2.jpg480×640 119 KB

I tried using the code provided at https://github.com/bhaskar-anil429/voltage-monit_python/blob/master/voltage.py, with line 10 changed from

bus = smbus.SMBus(1)

to

bus = smbus.SMBus(2).

The screenshot below shows the output I get from running this script.

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Any suggestions on how to fix this?

2

Hi,
Is the 9V adapter plugged into 120V AC Source ?

Thanks

3

Yes, it is. Both 9V AC adapters are plugged into a 120 V AC source.

4

can you measure the voltage at 9V barrel connector.
it almost looks like there is no voltage at 9V terminals

5

You are right - that was the problem. Must have been a loose connection. It’s working now. Appreciate the help!