TTL to USB

[rkidwell1]

Hello,

I am going to be connecting my 280ah 12v battery bank with a JK BMS to my CERBO GX for monitoring only (the CERBO GX is also connected to my 560ah 48v battery bank using a REC BMS).

I’m slightly confused about the TTL to USB converter that I need. The directions show to use an isolated TTL to USB and a 12v to 5v buck converter to power the converter off of the 12v power output on the GPS plug on the JK.

There is a YouTube video by @Jasonschmidtschannel that shows a very simple TTL to USB converter/cable where he does not have the power hooked up (just TX, RX, and Ground).

https://youtu.be/ZwTxyB65Aas?si=ANnG9Vg24jI2ZCmz

Is any reason this cable would not work in the same manner with just TX, RX, and Ground connected to the GPS connector (using a JST MX 1.25) on the BMS?

https://a.co/d/7oxHVzg

Thank you!

[mr-manuel]

The adapter is not isolated. Check the docs what that means.

[rkidwell1]

Okay, this one is isolated. Do I need to run a 12v to 5v buck converter from the battery voltage to VCC pin and switch the jumper to 5v? Or do I need a 3.3v buck converter?

https://a.co/d/2yNlqpm

https://www.deshide.com/product-details.html?pid=303386&_t=1661499873

[mr-manuel]

Does not matter. Important is that you set the jumper to the voltage you chose.