Hi everyone,
I’m planning to connect four Victron VE.Direct devices to a Raspberry Pi running Venus OS in my camper:
SmartSolar MPPT 100/20
SmartSolar MPPT 100/50
SmartShunt
Orion XS 12/12-50A
I’m considering two DIY approaches and would appreciate feedback before buying the components or connecting anything to the Victron devices.
Option 1: One FT4232HL board with four UART channels
This would use a single USB connection to the Raspberry Pi. I would add one ADuM1201 digital isolator per UART channel to isolate TX and RX for each VE.Direct connection. The seller says the UART signals are fixed at 3.3 V and that the board’s 3.3 V / 5 V jumper only changes the external VCC output. However, the seller cannot provide a schematic, so I would verify these levels myself.
The main design question for this option is how to power the Victron side of each ADuM1201 while maintaining independent galvanic isolation for all four VE.Direct ports.
Option 2: Four FT232RL USB-to-TTL modules advertised as isolated
These modules are sold as “ADuM3201 FT232 isolated USB-to-TTL serial modules” with selectable 3.3 V / 5 V levels. I would use one module per Victron device, connected to the Raspberry Pi through four USB ports or a USB hub.
The listing appears to show an ADuM3201 for signal isolation and another component that may provide isolated power, but I have not obtained a schematic or confirmed the isolation of the actual board. I also need to confirm whether the TTL side is powered internally from USB, what the jumpers control, and whether its VCC pin can be left unconnected to VE.Direct.
In both cases, I would make four cables with JST PH 2.0 mm, 4-pin connectors, carefully verifying the VE.Direct pinout and TX/RX direction before connecting them.
Questions for the community:
Has anyone used an FT4232HL as four simultaneous VE.Direct interfaces with Venus OS? Does Venus OS detect all four devices automatically?
Is an ADuM1201 with one isolated channel in each direction suitable for full VE.Direct communication, including device detection and control?
For option 1, is it appropriate to power each ADuM1201’s Victron side from its corresponding VE.Direct port? Would its available current be sufficient, including any LEDs or other components on the isolator board?
For option 2, has anyone used these particular FT232RL + ADuM3201 isolated modules? Do they actually isolate both data and power, and do they work with Venus OS?
How would you handle VE.Direct devices with different 3.3 V / 5 V logic levels in either design?
Is there anything else I should check before using either option in a camper electrical system?
My goal is a safe, reliable and reasonably priced four-port interface—not just to get serial data working once. I’d appreciate any experience, schematics or measurements you can share. Thanks!
