For some time now, or always, my USB serial connection, for example, has been dropping out sporadically for 10 to 15 seconds. I only noticed this because there were cases where the connection was lost permanently until I completely restarted HomeAssistant.
supervisor log (Detecting many remove hardware)
I have the following log file entries in the supervisor log:
/dev/serial/ Disappears on permanent disconnection:
Some time ago, when the connection was permanently lost, you could see via SSH that the “Serial” folder for “/dev/serial/by-id/usb-FTDI_FT232R_USB_UART_AK05EMVN-if00-port0” was also not present in the permanently disconnected connection.
Restarting the Eltako USB Serial Gateway did not help.
Unplugging and plugging in the USB adapter did not help.
Restarting the Raspbarry (HomeAssistant) helped.
So I think it is due to HA and not to the USB serial adapter from Eltako.
Hardware conversion:
I have made a few modifications to the Raspbarry Pi to improve the problem in theory:
Pimoroni NVMe Base
Crucial P3 Plus SSD 500GB (NVME tested by Pimoroni)
Before, I had the original Pi5 27Watt power supply and an energy-saving USB SSD
Hardware losses still discovered
At first I thought that my problems had disappeared because I had 0 entries for a few days. But apparently this is not the main problem. I don’t think it’s the ELTAKO USB serial module either, as gpiochip14 etc. is also disconnected. Currently at least the connections are not lost permanently. But they are still disconnected several times a day for a few seconds.
Is it possible that the fge14usb is exceeding the 1.6 amp current limit of the raspberry pi 5 USB port (need to consider both normal and surge requirements)? Note: the 1.6 amp current limit cannot be improved by using a bigger power supply for the Pi.
Perhaps using a powered USB hub between the pi and Eltako my solve the problem.
Maybe I have another reason. I first replaced the 27 watt power supply with the 45 watt power supply. That solved my problems.
After that, however, I converted from USB SSD to NVME. I then plugged the USB-Serial Eltako connection into USB 3.0. Apparently you should avoid connecting USB 2.0 devices to USB 3.0 ports.
Before I did the whole conversion, I had the USB serial port mainly on USB 2.0
So the power supply + USB 2.0 port probably helped. I’ll keep an eye on it for a few more days.
Here I discovered the reference to the Pi 5 and USB 2.0 topic.
Translated from the article:
Note on the USB 2.0 port topic
In many videos it is said that certain peripherals only work with USB 2.0 ports. This is also true, but only applies to the Raspberry Pi due to various special features of the USB chipset. I myself use an Intel NUC and can use the Homematic or ZigBee stick on the USB 3.0 port without any restrictions.
Interference can always occur directly on the USB 3.0 port, but not if you use a USB extension cable*.
@MaxK: I hope that a USB serial converter does not require more than 1.6A
But I have also read that some power supplies have DC voltage problems. Maybe the original PI power supply was defective and caused fluctuations. Especially as the FGW14 Eltako RS485 LAN gateway is supplied with 12V via its own bus.
I now have the solution, it is now running stable throughout.
Mar99 had the same problem. But with an HP server and an ELTAKO 300 stick. He found out from Eltako support that his 10 metre USB cable was unsuitable. A maximum of 2 metres is recommended. He tried a 2 metre USB 3.0 cable and it worked.
All my problems are now gone. I had initially tried it directly on the 2.0 port. That worked fine. Then I got rid of my 2 metre USB 2.0 cable. I now use a UGREEN USB 3.0 extension cable 5Gbps USB 3.0 A data cable nylon and aluminium braided case. And now I have a stable connection.
