By removing power supply from the server, the LED from the equipment don’t reporting an error and also, not iBMC reports any problems.
If the power cable is diconnected from the server, LED and iBMC reports a problem.
When the power cable is removed from PSU, the sensor from the server generate an error that the PSU has some issue (like a faulty PSU). If the PSU is removed from the server, the sensor from the server feels that the PSU is not present physically and this event can be generated only by the human intervention.
In case that something wrong will happen with the PSU (let say a piece from the PSU is faulty), but PSU is present into the server, the iBMC generate an alert related to this event.