question

bryancox avatar image
bryancox asked

VEDirect to USB cable and Arduino

I'm trying to connect my Smart Solar MPPT 75/15 to an Arduino UNO Wifi Rev2 via the VEDirect to USB cable. The 75/15 is configured for normal Tx, so as I understand it, it SHOULD be transmitting character data every second.

The Arduino sees nothing. So, I'm inclined to suspect one of the following:

1). The VEDirect to USB cable is opto-coupled, rather than inductively coupled; and the USB side of the connector requires 5v power, which the Arduino does not supply.

2). The Smart Solar does not transmit character data via VEDirect when it is operating in bluetooth networking mode.

3). The Tx and Rx pins are reversed.

Can anyone confirm/eliminate any of these possibilities, or suggest a solution? I'm tempted to direct-wire the two devices, but I'd prefer to avoid that if possible.

Thank you for your help.

VictronConnectVE.Directarduino
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5 Answers
Mike Dorsett avatar image
Mike Dorsett answered ·

The USB Cable does have an isolating chip in it that requires power on both the USB and VE direct sided. This also will work with either 5 or 3.3v.

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VK2EVA avatar image
VK2EVA answered ·

You don't need the USB cable. You'll need USB host and a mess of other things and work to use it.


You just need tx,Rx and gnd between them.


Get some ph2.0 jst-xh pigtails and you're set!


The ve.direct does need power to operate from both sides, it's isolated

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bryancox avatar image
bryancox answered ·

Thank you both for excellent, concise answers.

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sebastien-bouthillette avatar image
sebastien-bouthillette answered ·

I'm looking to do something similar. I want to access my Smart Solar MPPT 75/15 remotely. Have you succeeded and if you did, can you share your setup?

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lars78 avatar image
lars78 answered ·

i´m using an arduino nano to read the data from a BMV-712 smart via ve.direct. tx/rx connection that's it. I'm also using the same ve.direct from the BMV to connect to a raspberry pi via RS232 to USB

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