Output overvoltage protection is intended mainly to protect the load circuit.
Overvoltage protection operation explanation

※Transformer turns ratio = Output winding:Auxiliary winding = 1.0:1.5
Many ICs detect overvoltage of the auxiliary winding voltage and perform
protection operations.
The auxiliary winding voltage and auxiliary winding overvoltage protection
voltage vary depending on the IC.

Generally, the appropriate setting for output overvoltage protection is
2 to 3 times the rated voltage.
Whether auto-restart or latch is better depends on the user's design philosophy.
Overvoltage Protection Test

There is a possibility that the overload protection will operate before
the overvoltage protection operates.
It is recommended that the output current during the overvoltage protection test
be approximately half of the rated output current and that the electronic load be in C.C mode.
Output overvoltage abnormal operation under overload.
An abnormal operation may occur, such as the output overvoltage protection
being activated when the output is overloaded.
This section explains this abnormal operation.
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