Fireworks inside UPS? Or maybe not...

[BigBadAl]

Friend of mine handed me a baby APC 350 VA UPS and said see what you can do with that.

Eminating from the UPS is the remnants of the smell of the magic smoke escaping from something fundamental to its operation.

Upon dismantling I find that other than the scorch marks surrounding the immediate area where 2 mosfets 'took one for the team', the whole UPS is immaculately clean, like new in fact.

The 2 mosfets, I suspect they are mosfets, are damaged to the extent that I am only able to identify some of the markings from them.

First up is what looks like the manufacturers logo/trademark which is an uppercase letter 'F' in bold typeface.

Next to that is 1J03SR
And on the next line is 7533****

I don't know what the ****'s are or how many of them there are....

Now, the way I see it is I have 2 options...

1) Find someone with one of these UPSes (bk350ei) and have them open it up and give me the ID off the mosfets.
or...
2) find someone with access to the schematics who could identify the correct devices.

I can see the silk screening in the PCB identifying the two devices as Q5 and Q6.

If anyone could assist with identifying these devices I would be eternally grateful.

Many thanks

 

[Gorankar]

Once you figure your own time into it, it is usually cheaper to replace than fix at that level. A new one can be had for around $100, and 350VA UPS from APC, Cyberpower, and others can be had for much less than that.

Email APC and see if they will provide you with a schematic and parts listing for it.

 

[Jorona]

Did you bother calling APC? I've called for the specs on a fet in a Smart ups 750XL and they just told me it.

 

[Nexillus]

Would just call APC. or buy a new one at 350VA which isn't that expensive to begin with.