Reason:

(1) Excessive testing.

(2) Power module is faulty.

Solution:

(1) Review the test conditions.
If within the ratings, check the sensitivity of the sensor, the mounting condition and whether the connectors are correctly connected.

(2) With the error occurring (before resetting), remove the front filter panel and check the position of the power module where the red LED is lit and what LED is lit from the left.
Check whether the amplifier panel fan is running.
Click here for details. PM.FLT causes and methods of investigation