APC RS 800 Completely Dead

[Pyrotech]

Re: APC RS 800 Completely Dead

hmm, 10 minutes to reedit, not long enough. Here is the picture.

[Pyrotech]

Re: APC RS 800 Completely Dead

hmm, 10 minutes to reedit, not long enough. Here is the picture.

[Pyrotech]

Re: APC RS 800 Completely Dead

HI, here is the picture, could not edit picture after 10 minutes...

[Pyrotech]

Re: APC RS 800 Completely Dead

Hi, I read the russian forums about RS1000 schematics and they said to piece it together from 218 to 245, to me it looks very much like 218, 228, 231, or 232. Sorry about the huge pictures, if you resize them they look ok smaller.

[Pyrotech]

Re: APC RS 800 Completely Dead

I give up with pictures...

[Pyrotech]

Re: APC RS 800 Completely Dead

Hi, ha did some more trobleshooting and read the labels on my XS 800 chips says RS 800. Even has a connector for the 10/100 option on the RS 800. So its the same board 640-0189D.

[Pyrotech]

Re: APC RS 800 Completely Dead

Hi,

It would be cool to know how you disassembled the UPS.
I have an 800i with all LEDs flashing and would like to know if i could fix it by myself.

and where are the three fuses are located?

bye Zoomer

Hi, Zoomer, sounds like your UPS is stuck in program mode. Program mode is entered by first turning off the ups, then hold the power button 10 seconds, which makes all led light, pressing one, yellow should flash, then press, red and yellow flash, press again, all red, red, yellow light up. check your power switch maybe its stuck down. It should have a distinct clicking when depressed. Other wise its in the power switch circuit. I could probably fix it. I got some schematics of the power switch.

[Pyrotech]

Re: APC RS 800 Completely Dead

Hi, well, I recharged my batteries in another ups, and replaced F1 fuse that was blown. Its started charging! I tested it by letting it run on batteries with my Oscope plugged into the battery backup. The battery went down to 24 from 27.5 after several hours. Then I plugged it back in and its charging up past 25 already. But I noticed that Q40, Mosfet is very hot, and the other mosfets are not. Also the IC11 12V regulator is hot too. F1 is very warm too, and its connected to the drain of Q40, and the other side of F1 is connected to battery ground. I bought some MOSFET and going to replace it tomorrow. Wish me luck I may have fixed it!

[Krankshaft]

Re: APC RS 800 Completely Dead

Well my passively cooled RS 800 gets pretty toasty as well. I can feel it through the casing and this is when it's in standby mode. Not plastic melting hot but warm.

My XS 900 has a little internal cooling fan so it runs cooler.

It may be just the design that the FET runs hot APC saved on a heatsink.

Unless the FET is in circuit (in parallel) with the other FET for example then there is a problem.

Is that a charging FET?

[Pyrotech]

Re: APC RS 800 Completely Dead

Well my passively cooled RS 800 gets pretty toasty as well. I can feel it through the casing and this is when it's in standby mode. Not plastic melting hot but warm.

My XS 900 has a little internal cooling fan so it runs cooler.

It may be just the design that the FET runs hot APC saved on a heatsink.

Unless the FET is in circuit (in parallel) with the other FET for example then there is a problem.

Is that a charging FET?

Hi, yes it gets toasty, especially the big transformer, must be over 130 degrees too hot for a finger. Q40 is near two other identical MOSFETS but they don't get hot. The fuse is connected to the mosfet drain and is rated at 2A and was blown. I found a replacement in another forum and bought some from Digikey.
I am going to replace it as a precaution and see if it helps. Once the battery charges it not as warm too. The other 2 mosfet near it don't get hot at all. I ohm tested the mosfets and they seem ok. The IC11 is hot buts its a 27vdc to 12VDC regulator. Probably its ok. There is a cap 330uf 50V that gets warm too. Might replace it too. The heatsinked mosfets seem fine, nothing too hot. I tested the inverter and its ok. Converts the battery to 120VAC when power plug unplugged.

I put a socket on the F3 fuse and am going to remove it and do an amp test of the mosfet, it draw much less than 2 amps or the mosfet might be blowing it. I think I got lucky with an easy repair with no schematics!!! I am still going to find those schematics, strange the Russians must not get ES, RS, and XS APC over there or they would have schematics.


Thanks for responding.

[Pyrotech]

Re: APC RS 800 Completely Dead

Hi, well you can never be too careful. I put the ups XS 800 back together after replacing Q40 and checked the checked the F1 current, 200-500 ma, good for a 2A fuse. It was runing when one of the fuse links blew. I took it apart and repaired the fuse link and put it back together. Then I plugged the battery in backward accidently. Boom there when the board fried, well at least it didn't cost me anything for the ups and only spent $15. I did learn alot about ups, just made a stupid mistake, you can never, never be too careful... The funeral was today in the trash bin...

Don't feel too bad, I fixed a rootkited computer for a customer today, took 4 hours to remove it. So at least I got something done right!!!!

[Behemot]

Re: APC RS 800 Completely Dead

I've been doing whole bunch of these UPSes lately. Mostly when they go crazy, the problem is with small SMD capacitors especially near the SMD MOSFET and main processor as both heat a bit, usually it is darkened around the MOSFET. This part is simialr in all UPSes from those plastic BE550/BE700CP (and similar markings, depends on region and configuration) all the way up to Smart-UPS 2200 VA (brick version), usually 10- and 22uF worse-than-general purpose caps.

You need two soldering irons or micro soldering pens to heat both legs simultaneously, if you try to bent one side than the path tears off, these PCBs are PoS. Than you can use GP caps lying on board with legs bented.

However, last two UPSes also show strange behaviour. After the repair they work just fine when turned on. But as you turn them on, after a little while all the LEDs start flashing showing internal failure. Than it soemtimes turns on normally, sometimes not. In this last case, it starts and stops flashing in short interval, do not know what else is bad. Maybe processor took a hit when those caps went bad? They tend to go to compelte hell, I've seen anything from 80 ohm ESR half the capacitance to 22uF cap having 0,2 uF 30 ohm etc.

[runderwo]

Re: APC RS 800 Completely Dead

Hey Behemot, not sure if this is related to your problem or if you will see this reply but when testing a Back-UPS XS 1500 repair (also all bad 22uF 16V SMD caps, which I replaced with normal 105deg caps soldered to the SMD pads), I noticed this fault condition also (a short time after power up, all leds flashing except Power on solid). I noticed that when I removed the battery the fault went away immediately. I checked charging voltage (good, 27V) and battery voltage (good, 13.8V), then realized I needed two 12V batteries in series for a valid test. :-) When I hooked two batteries in series up (one known bad but still ~12V), the fault condition went away immediately and the unit was working. So, maybe all you have to do is check your math.