Anyone know how to repair a UPS?

Not much help I'm afraid, but if you replace it then buy it at Costco and get a forever full replacement warranty.
 
I don't want the little ones, I want another enterprise one because they can be adapted to an external battery pack without fear of cooking the charger. Next battery replacement I was planning on getting four 35Ah wheelchair batteries for it, which would give 5x the runtime of the built in pack.
 
Q™ said:
Forever replacement warranty.
Click to expand...

More like "Return policy subject to manager approval, likely to be denied on 8 year old product". Just google it and you'll see it's a nightmare trying to return old products, not to mention it really makes you look like a douche. No thanks.
 
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When the series of power outages occurred, it's possible that there was a brief surge or brown out that contributed to the problem.
It could be a problem with a feedback circuit to monitor voltage or current or that part could be doing it's job and shutting it down when it falls out of regulation because something else it borked.
The feedback / control on an active pfc or simulated sine model will be more complicated than a basic modified sine one.
My money would be on a bad MOSFET or diode.

UPS can be dangerous to work on so be careful. It doesn't take that much current to stop your heart.
Things like this can also be a pain to solder (massive traces / power planes just suck up all the heat)
 
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And using a hotter soldering iron isn't the answer. You need a massive tip that acts as a "thermal capacitor" and can dump a lot of heat into the large "thermal load" of the large traces quickly. And a higher wattage (but still temperature-controlled) iron to back it up is also required. Weller's W-60 or W-100, with a large tips are nice for this sort of thing.

More PCBs are destroyed by using too-small soldering irons/tips than anything else. And don't press hard. Instead, make sure you quickly feed fresh solder and flux into the area of contact between the soldering iron's tip and the trace/joint so a good filling or "bridge" of solder is immediately available to conduct the heat from the tip to the trace rapidly. Remember that fast thermal transfer requires a large cross section of thermally conductive material (in this case, the molten solder). A dry soldering iron tip pressed to a flat PCB trace theoretically produces a single point of contact. And a geometric point has NO surface area or cross section. You want to melt fresh solder with fresh flux at that point immediately to produce a good heat path.

Avoid roasting the foil for too long, and avoid mechanical forces on the foil while it is hot. The foil is held to the fiberglass board with something like glue. When hot, it melts. Be gentle on traces when they're hot!

This is all true for protecting the semiconductors as well. Time is the enemy. Have enough stored heat and enough heat transfer capacity to get the job done well, but quickly.

Soldering is an art.
 
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I keep an arsenal on hand...

15W for fine work
25W for typical duty
40W for bigger stuff
Then a 100/140W gun for larger chassis-type connections often encountered in old tube amps and such.

Along with various sizes of solder wick, a solder sucker, a few different gauges and compositions of solder, flux pen, etc. :)
 
myipcam said:
Wow you mentioned Weller! That's something you don't hear much. I have a digital temp controlled one. The are the best!

Yes, soldering is an art And, there's even a milspec for it!
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Weller used to be good. I'm not so convinced anymore, these days they can't even be bothered to put fuses in their products.
Whoaru99 said:
I keep an arsenal on hand...

15W for fine work
25W for typical duty
40W for bigger stuff
Then a 100/140W gun for larger chassis-type connections often encountered in old tube amps and such.
Click to expand...
What you need is a temperature controlled soldering station. No way in hell I'm using a 15w soldering iron for 'fine work'.
 
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tangent said:
Weller used to be good. I'm not so convinced anymore, these days they can't even be bothered to put fuses in their products.

What you need is a temperature controlled soldering station. No way in hell I'm using a 15w soldering iron for 'fine work'.
Click to expand...

I have no problems with it. But perhaps we define fine work differently. By fine work I mean small through hole PCB stuff, although I have done a few minor SMD repairs with it too.
 
It seems like these UPS systems failures are quite prevalent. Google shows many results for similar issues. If the power line has to be conditioned for UPS, then that is just messed up. It's in the name UPS. In my book, power loss is not the only interruption. The UPS should handle line conditioning, noise suppression, ground-faults while providing clean power to its devices. Maybe, I am expecting more than a simple sine wave inverter with a fast acting diode to trigger transfer, and, oh those wonderful batteries... that seemed to have little usable power and much less shelf life..

Which brings me to this: for security and peace of mind we embark on this surveillance video project... only to keep worrying if the UPS is working right or the system is up all the time etc.

price to pay.. more technology, more things to keep checking/worrying/fixing...
Yeah, once it is up and running, only routine maintenance.. I get it.
 
Whoaru99 said:
I have no problems with it. But perhaps we define fine work differently. By fine work I mean small through hole PCB stuff.
Click to expand...
My Weller has been working perfectly fine for me as well. I don't use it extensively but when small projects come up, it is the go-to iron. In industrial setting, these things are on for 12hrs a day and keep working so, not sure if others got a bad unit... I leave temp around max 680 or less below for most work.
Never knew about tip cleaner.. that innocent looking bush does wonders for the darkened tip..
 
myipcam said:
It seems like these UPS systems failures are quite prevalent. Google shows many results for similar issues. If the power line has to be conditioned for UPS, then that is just messed up. It's in the name UPS. In my book, power loss is not the only interruption. The UPS should handle line conditioning, noise suppression, ground-faults while providing clean power to its devices. Maybe, I am expecting more than a simple sine wave inverter with a fast acting diode to trigger transfer, and, oh those wonderful batteries... that seemed to have little usable power and much less shelf life..

Which brings me to this: for security and peace of mind we embark on this surveillance video project... only to keep worrying if the UPS is working right or the system is up all the time etc.

price to pay.. more technology, more things to keep checking/worrying/fixing...
Yeah, once it is up and running, only routine maintenance.. I get it.
Click to expand...
You forgot surge suppression. I'm not sure your typical UPS handles ground faults, it certainly should but I don't recall seeing that spelled out in documentation.
 
myipcam said:
My Weller has been working perfectly fine for me as well. I don't use it extensively but when small projects come up, it is the go-to iron. In industrial setting, these things are on for 12hrs a day and keep working so, not sure if others got a bad unit... I leave temp around max 680 or less below for most work.
Never knew about tip cleaner.. that innocent looking bush does wonders for the darkened tip..
Click to expand...
Brass sponge or bust.
 
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Brass sponge or what looks like brass wool (coarse). Got it as part of solder kit and couldn't believe I never used it. Threw too many Weller tips (back in the day) which now I understand could've been reconditioned using this... those tips are not cheap either...
 
myipcam said:
It seems like these UPS systems failures are quite prevalent. Google shows many results for similar issues. If the power line has to be conditioned for UPS, then that is just messed up. It's in the name UPS. In my book, power loss is not the only interruption. The UPS should handle line conditioning, noise suppression, ground-faults while providing clean power to its devices. Maybe, I am expecting more than a simple sine wave inverter with a fast acting diode to trigger transfer, and, oh those wonderful batteries... that seemed to have little usable power and much less shelf life..

Which brings me to this: for security and peace of mind we embark on this surveillance video project... only to keep worrying if the UPS is working right or the system is up all the time etc.

price to pay.. more technology, more things to keep checking/worrying/fixing...
Yeah, once it is up and running, only routine maintenance.. I get it.
Click to expand...

Perhaps I'm speaking to which most already know but, unless the UPS of topic is a true on-line/double conversion unit, the inverter part does nothing the vast majority of the time (not until the AC mains power goes out or drops below a certain threshold).

For me, I'd consider line conditioning mainly as voltage regulation, frequency stabilization, and perhaps "cleanup" as in reduction of THD of the mains power. But, most UPS don't do any of those things on a regular basis. And, if it's not a pretty good one, when the power goes out and the unit inverter kicks in, it might be even worse than the AC mains in the aforementioned regards - intended primarily just to facilitate orderly shutdown of systems and momentary outages.

Surge protection and noise filtering may be incorporated into UPS and even incorporated into the point of use devices themselves. Those I consider a separate thing from line conditioning but opinions certainly can vary in that regard.

In one of my other hobbies, stereo gear, line conditioning is a frequent topic of discussion. Some of the high end power conditioners in that arena (and perhaps others) are in effect, high power amplifiers with regulated output stages working at a fixed frequency and very low distortion. These are not the garden variety switching inverter type devices. Very "clean" power coming out of those "hi fi" units. Whether or not it makes any difference is another matter, and depends to some degree how crappy is your normal mains power and the inherent qualities of the power supplies in the attached gear.
 
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What would be better:
Since,
Computer power supply only provides 12v, 5v and maybe 3.3 or 3.2v based on newer low power logic.

LCD monitors are also same, 5V for display and maybe 12v for backlight and audio(if any).

So, wouldn't it be better to just use DC-DC converters to get 5v and 3.3v from a nice large 12v marine battery and splice that into computer power supply with a high power diode (so PSU won't feed the converters backwards)... and a diode coming from PSU so converters won't back feed PSU. Sort of like a bridge rectifier.

There are adjustable dc-dc converters available and they are not expensive. These are more efficient than dc-ac type... aka inverters in regular UPS. Remember, we are going 12v to lower not 12v to 110ac... losses are minimal of course depending on the type of converters.. but they are much better in general.

The idea is, considering 0.7v diode drop, adjust the converters to just about or 0.2 volts or so below average PSU voltages and splice them in.

In operation, a battery charger will keep charging the battery all the time and DC-DC converters are online all the time feeding the motherboard and peripherals along with PSU.

When power fails, nothing happens.. everything keeps running (until battery runs out of course). And, when power comes back, the charger starts charging.

Of course, some details such as how will the charger know battery full etc., when there is constant drain.. (shouldn't be drawing much current during PSU power - set converter below psu) need to be worked out and not a big deal once voltages and current values during operation are known.. this could be further mitigated with a relay and a "super capacitor" which could provide just enough power while a relay switches converters to battery (if proper battery charging is Important - different design)..

Monitoring can be done simply using an Arduino and some code along with few components... actually, if you just to shutdown pc after power loss, not a whole lot is required. OTH, monitoring voltage and battery status etc. would require very few components and few lines of code.

You may wonder, why go through all this?
1) no need for expensive pure sine wave inverter UPS.
2) efficiencies. Precious battery power is lost during conversion of 12v to 110vac.... and, back to 12v, 5v, 3.3v by the PSU!
3) avoid all sorts of these overloads and failures.
4) granted it is tailored to specific devices, run time could be much better and no need for any special batteries..


Just a thought ...
 
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myipcam said:
What would be better:
Since,
Computer power supply only provides 12v, 5v and maybe 3.3 or 3.2v based on newer low power logic.

LCD monitors are also same, 5V for display and maybe 12v for backlight and audio(if any).

So, wouldn't it be better to just use DC-DC converters to get 5v and 3.3v from a nice large 12v marine battery and splice that into computer power supply with a high power diode (so PSU won't feed the converters backwards)... and a diode coming from PSU so converters won't back feed PSU. Sort of like a bridge rectifier.

There are adjustable dc-dc converters available and they are not expensive. These are more efficient than dc-ac type... aka inverters in regular UPS. Remember, we are going 12v to lower not 12v to 110ac... losses are minimal of course depending on the type of converters.. but they are much better in general.

The idea is, considering 0.7v diode drop, adjust the converters to just about or 0.2 volts or so below average PSU voltages and splice them in.

In operation, a battery charger will keep charging the battery all the time and DC-DC converters are online all the time feeding the motherboard and peripherals along with PSU.

When power fails, nothing happens.. everything keeps running (until battery runs out of course). And, when power comes back, the charger starts charging.

Of course, some details such as how will the charger know battery full etc., when there is constant drain.. (shouldn't be drawing much current during PSU power - set converter below psu) need to be worked out and not a big deal once voltages and current values during operation are known.. this could be further mitigated with a relay and a "super capacitor" which could provide just enough power while a relay switches converters to battery (if proper battery charging is Important - different design)..

Monitoring can be done simply using an Arduino and some code along with few components... actually, if you just to shutdown pc after power loss, not a whole lot is required. OTH, monitoring voltage and battery status etc. would require very few components and few lines of code.

You may wonder, why go through all this?
1) no need for expensive pure sine wave inverter UPS.
2) efficiencies. Precious battery power is lost during conversion to 110vac.
3) avoid all sorts of these overloads and failures.


Just a thought ...
Click to expand...
Setups more like this have been used in data centers for years, except they simply replace the traditional power supply.
 
Yeah, ok.. that would work as well. My thought was to just put a connector in the back of PC to add in the aux power which functions as ups. If it is not required, simply unplug and it is regular pc with it's own psu.
 
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