When you see "apc ups power system error 02000 link," do the following in order. UPS units contain high voltage even when unplugged.
A small business experienced "apc ups power system error 02000 link" on their APC SMT1500RM2U during a thunderstorm. The UPS shut down, taking down a NAS and two switches. apc ups power system error 02000 link
If you have a serial cable (not USB) and a terminal program (PuTTY), connect to the UPS at 2400 baud. Send the command: Y (capital Y) followed by Enter to get the smart status. Look for lines: APC UPS Power System Error 02000: Understanding and