Unable to connect VM-3P75CT

I recently purchased a VM-3P75CT (brand new, locally in SA from http://createenergy.co.za) but I am having trouble getting my cerbo gx to see it. I did a fair bit of trouble shooting with the docs and on my own with no luck.

What works:

  • Powering on the device the green LED comes on and stays green
  • Initiating a reboot the green LED returns to green as expected
  • Initiating the exact factory reset (many times), the green LED goes through the correct sequence as per the manual (and returns to solid green)
  • Connecting an ethernet cable and monitoring the traffic on my router I can see it is offered and accepts an IP from my DHCP server (and responds to pings)
  • When connected via ethernet, if I do a port scan I can see one tcp port open 19200 and nothing else (more on that at the bottom)

What does not work:

  • When connecting via ethernet, my cerbo gx does not find the device (initiating auto scan)
  • When connecting via ethernet, my cerbo gx does not do anything if i manually configure the ip (as leased by dhcp) and some port combinations.
  • When connecting via ethernet, I expected to maybe find port 502 open on the device but it does not appear to be.
  • When I daisy via VE-CAN (with terminating caps) either on the mppt or on the other open VE-CAN port on the cerbo-gx it is not picked up/detected
  • Any of the above with the victron connect app - does not see it either

Other info:

When I look via wireshark what it declares during the DHCP query sequence i see some info, not sure if any of it helps in terms of versions etc (serial masked):
Victron-VM-3P75CT-HQ24096****.local: type TXT, class IN, cache flush
Name: Victron-VM-3P75CT-HQ24096****.local
…
TXT Length: 9
TXT: victron=1
TXT Length: 11
TXT: prodid=A1B1
TXT Length: 18
TXT: serial=HQ24096****
TXT Length: 13
TXT: appver=1.4.ff
TXT Length: 14
TXT: bootver=1.2.ff
TXT Length: 8
TXT: mode=app
TXT Length: 11
TXT: updatable=1
So from that (and the LED) i would say it is for sure in full app mode

Port 19200:
I did a bit of digging around port 19200 and it looks like when i curl to it (force http 0.9!) then I get back a busy stream of what looks like MODBUS ASCII messages (:[addr][func][data][crc][br]) if i am not mistaken (Modbus - Wikipedia - ASCII section). I have been meaning to write some python to decode some of it but it I dont have time at the moment and need to get this working)

Here is an example:
:4AAAAFD
:2AAAAFF
:4AAAAFD
:4AAAAFD
:A50220054582D
:A552200BD1DFA
:A5A2200BD1DF5
:A0922004600DA
:A50220052582F
:A552200BB1DFC
:A5A2200BC1DF6
:A0922004700D9
:A502200505831
:A552200BC1DFB
:A5A2200BC1DF6
:A0922004800D8
:A34220000000000F5
…

Based on what the device is doing (LED and also the output from the port above) it appears to be working…? I just cant get my cerbo gx to see it and I suspect I am just doing something daft.

Thanks,
Riaan

Did you put the latest firmware (1.06) on it with victron connect?

I am using the victron connect mobile app - it looks like it needs to be able to detected it before that is possible. Is there another way?

I don’t know. Did you use normal LAN cables with VE Can? I have 2 VM-3P75CT and they worked right out of the box.

Yes, I was expecting the same from what i read on reviews, etc before buying it. I did use normal lan cables yes on ve-can - that an issue?

Ah, you mean via the pc app - I am on linux so that is probably going to be my next problem :smiley:

I see there is a app for linux - will have to give that a try. Was just hoping it would not have to be so much effort

No I meant the mobile app.
Normal LAN cables is not an issue

Ok, great, but is it possible to update the firmware if the device can not be detected?

I don’t now, I don’t think so because it’s not visible in the VRM.

When you open victron connect on your mobile, VRM, you choose your installation. Did you then choose devices?

Is the Cerbo/GX device on firmware 2.90 or higher?

It was from what I recall I think, but I have just now run an update to v3.42 - will try with that quickly

Ok, this is properly embarrassing. I should have updated my cerbo gx - now it can see it.

Thank you Ton

Just to confirm as well, VE Can also works now as expected, instantly picked it up on the cerbo gx

:+1:, I think that’s the preferred connection.

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