Re: New Members - please post your introductions here

Just tripped over this forum looking for information on a faulty UPS.

I have spent 50+yrs in the TV transmission/Radio Transmission and Studio maintenance electronics industry working at board level. This involved many different types of equipment from Transmitters / translators small and large, studio gear, Diesel generators, test equipment, etc, etc!!

Now retired and running a custom built 1000 + channel Computer controlled Christmas lighting display for six weeks over Christmas time, sequenced by...

Re: Powerware 9120 Online UPS



Thank you for your observations I will look along that track. When operating under normal conditions the battery has a permanent drain of 300 ma until it is exhausted when the UPS shuts down....

Re: Powerware 9120 Online UPS

Anybody still listening :-) I have a Powerware 9120 700 watt version that appears to be working perfectly but not charging the battery. The MUR460 gets very hot and had shorted, it's 1k 5 watt power resisistor load gets very hot, as does the chopper Fet driving it and the small Fet further on in the chain. Replacing the MUR460 with similar diodes immediately creates their demise with a short again. There doesn't appear to be any circuits around for this machine which I find very unusual, as I have worked at board level for over 50yrs.

Any...