i have two problematic MT1200 , they keep freezing (stop responding) and i need to restart them (by pulling the power cord from power outlet) to get them running again… This happens 2-3 times a day.

CPU temperature is over 60°C...
OS is 5.25...


What can i do to resolve this problem...

Since the device spec operating temperature range is -20 to +65C (which I think is ambient temp, not core temp) and your core is reporting +60C (I assume this is the reading after you reboot, and is not known to be incredibly accurate either) you probably already know the solution. On the health monitor, what is the second temperature read?

Example:

I tried to look right now but both of them are unavailable to me... Someone will reset them tomorrow.

But i have data from earlier before:

1st
ROS 5.25 firmware 3.07
Voltage 12.3 V
Temp. 42°C
CPU temp 63°C

2nd
ROS 5.24 firmware 3.02
Voltage 11.3 V
Temp. 41 °C
CPU Temp 61°C

If these temperatures are actual, I am guessing they are an outside installation? You may need to bail on that unit for an RB that has fans to help remove the heat or build an enclosure to do the same. Once they get busy, the temp can only increase and the CPU may be seizing due to over temp or they are halting as a self preservation step. You might create a script to send you notices if the temp goes above +60C so you can be closer to the action before they just lock up. Not a solution but it would help you to know if they are spiking in temerature along the way.

What power supply do you use? How many amps?

What power supply do you use? How many amps?

RB1200's have an internal power supply, using a standard PC cable to provide household power to it.

The temps are a concern, I agree. So a redesign of his network to get his router to a cooler location would be in order.