MPPT + Cerbo GX + REC-BMS not working

[MeltemiCaz (Bill X.)]

I am hoping that someone can provide guidance as to why my MPPTs are not showing up on my Cerbo GX.

I hope it’s something simple that I have overlooked.

Set up:

• 2 MPPT solar charge controllers wired to house battery
• Both connected using VE.Direct to Cerbo GX using the USB to VE.Direct interface cable (I don’t have enough VE.Direct ports)
• VE.Smart Networking turned on and have joined the network (I am trying to confirm that it is ok to use both VE.Direct cable and VE.Smart Networking)
• Both MPPT units show up on the Victron Connect app via BlueTooth

However, the Cerbo GX running the new UI 3.5 sw does not show them in the device list and I do not see the PV controller on the overview screen.

Thoughts!

Thanks in advance!

[Sten (Sten Sørensen)]

Have you tried to move the usb to ve.direct interface to another usb port on the cerbo gx. The left most port on the cerbo is power suply only.

[pwfarnell]

DO NOT run VE Smart Network and VE Direct cable connections at the same time, these are an either or thing. The Cerbo does not partake in VE Smart Network so there can be erratic results. Turn this off first.

Good point about the power only USB.

The other point is try VE Direct cables on the MPPTs as a trouble shooting check temporarily removing another device.

[MeltemiCaz (Bill X.)]

VE Smart Networking is turned off

I’ve just run some tests:

Working: both MPPT units with no VE.Direct cable attached
Working: MPPT <—> VE.Direct port of Cerbo GX using a spare VE.Direct cable
Not working: MPPT <—> VE.Direct extension cable to USB cable direct to Cerbo GX
Not working: MPPT <—> VE.Direct extension cable to USB cable to USB powered hub

I took a VE.Direct to USB Interface cable and extended it by splicing it to a VE.Direct cable for a total length of approximately 7 meters (20 feet) using a Deutsch connector.

I wonder if the USB interface is unable to work with an extended VE.Direct cable? VE.Direct is just RS-232, so I would think it will work ok. I put a couple of chokes on the connector, but that made no difference.

As you can see from the picture, we just matched the 4 wire colors.

Does anyone have the pin out diagram for the VE.Direct connector that is attached to the USB interface cable. May be that there is a cross over wiring situation here. I need to do some research.

[MeltemiCaz (Bill X.)]

I am looking into swapping pins 2 and 3.
.
https://www.tarthorst.net/victron-ve-direct/
,

[pwfarnell]

Here in the Victron tech spec for VE Direct.

DIY cables are a common feature in VE Direct connection faults.

VE Direct Protocol

[MeltemiCaz (Bill X.)]

This is great information. Thanks for posting! I will head down to the boat and change the wiring to match. Hopefully this is the issue.

[MeltemiCaz (Bill X.)]

With help from this thread, I figured it out. I needed to ignore the wire colors and just ringout the wires through my addition of the Deutsch connectors following the pinout assignments from the USB side of the VE.Direct to USB interface cable.