Galvanic isolation of UART

I’m looking to establish galvanic isolation between my Victron MPPT solar charger with VE.Direct UART port (Rx/Tx/Gnd/Pwr 5V) and an Arduino monitoring the solar charging. At the moment it all works, but Victron recommend galvanic isolation and only provide this via a USB-UART cable connection ($expensive). I’m looking at the DFR0565 Gravity I2C Signal Isolator and wondering whether it could be repurposed for UART communication (SDA-Rx, SCL-Tx, Gnd). Any advice or alternatives would be appreciated.

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Yes, the DFR0565 is quite similar to what you’re after, I suspect that it won’t be an issue as you can just use the Data and Clock lines for TX and RX as you’ve suggested. The other option may be to go for optical isolation using a UART-Fiber transceiver depending on how your project is set up:

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Thanks for the response.

Unfortunately I’m not able to use the optical isolation module. The Victron MPPT Smart Solar Charger I’m connecting to has a JST-PH 4-pin communication port (5V, Gnd, Tx, Rx). I’ve successfully connected up the latter three to my Arduino and got serial communication working well. Victron recommend galvanic isolation as the MPPT has limited protection from what’s connected to their VE.Direct port. Their cables (USB-JST, Serial DB9-JST) provide this and I was looking to mirror this protection in my configuration, although it’s unlikely that the Arduino would be high risk (I’d think more the other way around).

My thought with the DFR0565 was to just use the Gnd/Clock/Data lines, but I wasn’t sure whether the Clock line was handled differently to the data line. If I go ahead with isolation, I’ll probably got it a go.