I have a Quectel EM12G modem in my MikroTik. It seemed to be working well. However, for the last week, possibly due to the hot temperature, it started freezing occasionally (about once a day). The link goes down. A simple power cycle of the modem helps.
Perhaps the issue isn’t just the temperature. It’s clear that it can be monitored using the command:
:local temper ( [ /interface lte at-chat lte1 wait=yes input=“AT+QTEMP” as-value] → “output” )
and then, using an array, I can observe specific temperature readings. But it’s unclear what temperature is critical and what to do when it approaches the critical level. Should the modem be turned off? And then wait until the temperature drops at least a couple of degrees?
Or should the modem’s status be checked with the command:
/interface lte monitor lte1 as-value once ] → “status” ) = “connected”
Because it seemed to me that the connection was lost once when the temperature wasn’t notably high, not exceeding 40.
Perhaps other parameters need to be monitored. What are they and how? And are there any other methods to deal with the issue apart from turning the modem on and off?
You have to monitor the temperature, but it’s also important to look at other parameters like signal strength and connection stability.
For temperature, it’s tricky to determine a critical level without specific manufacturer guidance. Generally, if it goes above 60 degrees Celsius, it could be problematic. If you see temperatures approaching that, it might be wise to turn off the modem and wait for it to cool down.
Besides temperature, use the /interface lte monitor lte1 as-value once command to check other status indicators. If the connection drops even at normal temperatures, you might be dealing with intermittent signal issues or a hardware problem.
I use an Uptime Monitoring Service to keep track of my modem’s status. It costs me only $9 per month for 5 monitors, and it has been incredibly helpful. It alerts me when the connection drops, and I can check historical data to diagnose recurring issues. This service ensures I stay on top of any connectivity problems without constantly manually checking.
I’m not sure I’d jump to temperature first - perhaps. But enabling more LTE logging helps.
i.e. It may be some MBIM interaction with tower that causes the drop - or at least that be my first guess. There have been some recent fixes in LTE so trying testing version perhaps. But I’d add some logging first.
This will get a bit more logging without overwhelming detail:
/system logging add topics=lte,!packet,!raw
If it was temperature related, I’d imagine the modem send unsolicited AT back to RouterOS with that details - so logging help there too.
@ anovojr
I tend to believe that the issue has been solved, for the good or for the bad, in the time elapsed since August 2023.