This question was originally posted by red on APC forums on 3/4/2008
I HAVE A SU700NET AND IT HAS A LOUD, HIGH PITCHED WHINING SOUND COMING FROM IT. THERE IS ALSO A LIGHT ON THAT SAYS TOO MUCH LOAD CONNECTED. WE HAVE HAD THIS FOR YEARS AND NOTHING HAS CHANGED AS FAR AS WHAT IS CONNECTED TO IT. ANY SUGGESTIONS?
This was originally posted on APC forums on 3/4/2008
Regardless, I'd still try reducing some load on the unit to see if there is any effect. How man load LED's are on the left side? If the overload LED stays on, you're probably going to want to just power cycle the unit, which would mean shutting off your load temporarily.