Excessive receive power tripping this alarm usually means the far-end transmitter is running hotter than expected for the fiber span, such as a short link using a long-haul-rated optic, and saturating a receiver's photodiode can itself distort the signal, so this alarm often points the admin toward attenuating the link rather than assuming the receiving optic is broken. For example, RxPower reading 3000 microwatts against a 2000 microwatt high threshold on a short campus link might mean an attenuator needs to be added because the far-end optic is simply too powerful for such a short span.