Re: Which, upper or lower one, is Power Supply 2 in S210?
As I understand it, we follow a general rule of thumb of: left to right, top to bottom.
So the top would be Power Supply 1 and Bottom would be Power supply 2.
I was unable to double check on physical hardware, as the people who test on the equipment are currently not available.
However if you have separate power lines connected to the supplies a check could be done as the power supplies are redundant. Just pull the power cord out of one and confirm with the alert. (This is what I was going to do to test)