Et112 disconnecting

Hi All,
I hope this is in the correct topic. If not, please move to the correct topic.

I have a Victron setup running the Venus on a Pi3.

The problem that i have, is that it seems the Et112 sometime disconnects from the system. The first time this happens was on the 23rd of April, then on again in the 28th. About the same time. Just after 9am.

I first thoughts it was many a usb not making proper contact. Pull the cable out, nothing, i them re arrange the usb cable on the pi, to see if its not the usb port(s). Nothing. Tho only thing that helped was a restart.

Same thing the second time. Only a restart helped.

Is this someone else also experienced before? If so, what would help?
Could it be that the SD is start giving up the gosht?

Thanks for the help in this regards.

When I’ve seen that in the past, it is because the USB port itself becomes unavailable to Linux, which usually means either some sort of electrical interference, or a power supply problem.

If you log into the Pi, and you run lsusb, does it show the device? Does /dev/ttyUSB0 or whatever port it was on exist? What I’ve seen in the past is that the port literally goes awol. Rebooting the device brings it back.

Thanks, i will run those command and have a look if it happens again.

Having said that, the system have been running without a hiccup since feb last year.
About 2 months ago i did change the power supply for the pi. It now runs directly from the batts.
Using a Meanwell 48 to 12v adapter. Then a 12v to usb adapter. So if its a power issue, that would probably be in there somewhere!

Thanks for the help Plonkster.

I had a similar issue with all my USB disconnecting. Swopped the PSU for a larger one (current) and the problem is gone.
So most likely your issue.


Now my question is, how big must the psu be?
The 48 to 12 is a 2.1a meaning, its 24w.
And then a 12 to 5v 5a? The Pi runs from the latter.

It might not be the amperage per se, but rather the stability under load. A better quality supply might be more stable while the Pi is running. For instance, better caps → more stable.

Could also be length of power supply wiring for the last 5v leg. In my experience I had to use very good USB cables with Pis to prevent the low voltage warning coming up under load. You can check for under-voltage errors with dmesg I think (been a while): firmware/raspberrypi: Add a get_throttled sysfs file by notro · Pull Request #2397 · raspberrypi/linux · GitHub

Lastly, I’ve had most success with taking 5v directly to the Pi’s 5v pins (more than one + grounds) and making the 5v actually 5.1v using an adjustable regulator. Be careful though.

Just an update on my situation with the ET112 power disconnecting issue.

So all of this start when i did some cable management for the DIY battery.
I put the USB power cable with the following cables in the same trucking:
1xUSB VE.Direct
1x USB to RS485
1x USB MK3.

I removed the USB power cable from the trunking, and so far, no issues.

So its probaley some form of magnetic field interference.

Interesting, some happen to the PI wifi. It start going nuts after all the above cables was connected.
Switched to wired LAN, and no more network issues.

1 Like

Thanks for the feedback. Interferrence can be a difficult problem to try and find as it is not very predictable.

For short cables this should not be too much of a problem, but if your cables are long enough that you can start putting them in trunking you should think about interferrence.

If you don’t have shielded cables, using a bit of tin foil will also help.
The higher the signal rate (baud) the more suseptable to inteference your connection will be.

And just like that, people will start to buy tinfoil hats!!


Yes, so one thing I’ve learned on this forum is that, if it worked fine, leave it… else trace back to what you changed! Normaly things dont just break because it wants to!!

…unless you are @TheTerribleTriplet … then the above theory goes through the window!!! :slight_smile: :slight_smile: :slight_smile:

Thanks for the help and input on this!

Being a radio amateur, ferrite chokes have long since become one of my good friends.
All cables between my radios and PC, mouse, keyboard, monitor, PI USB cables, SDR dongle USB cable, everything have ferrite beads on it.

Just last week I suddenly had a issue with my PC freaking out at certain times. I immediately sat back to think what I changed and remembered about a new serial cable which I haven’t put in to the cable tray and also haven’t choked with ferrite because it was only a temporary thing. I plugged out the cable and my problem was sorted.

RFI is 'n bliksem.