APC Back-UPS 1300 not charging battery

[Behemot]

Re: APC Back-UPS 1300 not charging battery

Replace ALL caps. Bloated primary caps can make the UPS go kaboom , bloated caps on output can disturb charging. And the small ones, well, I do quite a lot of APC units lately and there are ALWAYS some heavily out of spec.

[budm]

Re: APC Back-UPS 1300 not charging battery

So what happen? did you replace the caps?

[budm]

Re: APC Back-UPS 1300 not charging battery

If the batteries pack (12V x2) is at 28.8V that means each battery is at 14.4V already.
BTW, do you have VARIAC so you can adjust the AC Voltage feeding the UPS to see how well the charging circuit is behaving?
What DC on the output cap do you get at 118VAC?
The charging circuit is ON 24/7, just measure the on the cap (no batteries connected) when the power switch is turned off, the charging voltage should be there as long as you have AC feeding the UPS. All the UPS I worked on the charging is on no matter what the power switch is ON or OFF. In step 4 of the manual instruct you have plug the UPS into the outlet and let charge for 16 HOURS, then step 9 you hit the power switch.
It is easy enough to find out if the batteries is draining or charging in non-ups mode using DCA meter.

"Main cap CapXon 22uF 400V KW105C " We do not call it CrapOn for nothing at BADCAPS.NET


BTW, does it still show 22uF?
Right now we should wait until you install the new cap to see what will happen to the charging circuit to see you still get this effect: "that charger voltage 27.8V at input 117V, which raises to 30.9V at input 118V" 1V (< 1% change)) change in AC that causes 11% increase in the output Voltage.

[sambul83]

Re: APC Back-UPS 1300 not charging battery

At 117V input it gives 28.3V on output filter cap on utility alone, which is not enough to charge the battery currently at 28.8V. Do you know why it's discharging fast when not charging, but stops discharging if UPS is switched off?

Is it mandatory to detach all transformer wires before replacing the caps? Why do they cut the cap leads so close?

Now on the board:

Main cap CapXon 22uF 400V KW105C C817 VENT 16x21x7.5mm (low ripple rated, may be the cause to bulge?) (replace with Nichicon UCA2G220MHD6TN )
Running cap Nichicon 22uF 63V P105C 6.3x12x2.5mm (replace with Nichicon UPJ1J220MED1TD )
Output filter cap (Panasonic?) 470uF 50v 85C M 10x20x5mm (replace with Panasonic ECA-1HM471 )

Is that a good replacement?

[budm]

Re: APC Back-UPS 1300 not charging battery

"for output filter cap I got 30.9V on utility alone," it looks this SMPS power supply is for batteries charging, so if the AC input Voltage drops below 118VAC then you should see the output Voltage drops like you have indicated if it is not regulating properly. BTW, 2VAC drops from 118V is <2% changes which should not have much affect at all, and the US Voltage can be any thing between 110VAC~120VAC, so how many APC out there are not working due to slight Voltage drops.

"What does the big cap do? What brand do you suggest and supply source? It is the main filter cap for the primary side of the power supply to provide 160VDC to tun the SMPS circuit, just measure the DIA. and the Height of the cap then go to Digikey to look for the caps, the startup/running cap and the output filter cap should be LOW impedance/ESR type 105c rating (you can use PANASONIC FM/FC/FR series). The main filter can be something like this: http://www.digikey.com/product-detai...664-ND/1245993 you need to verify dimension. Just search DIGIKEY for what you need.
What are the original caps maker so you look up the spec sheet?

[sambul83]

Re: APC Back-UPS 1300 not charging battery

Thanks. We'll get busy replacing caps. Output voltage on LCD floats below input voltage. At 118V input and battery voltage 28.8V at no load, for output filter cap I got 30.9V on utility alone, 29.6V on battery and utility hooked, and 28.3V on battery hooked alone. At that input its charging OK. Will check at 117V input.

What does the big cap do? What brand do you suggest and supply source?

[budm]

Re: APC Back-UPS 1300 not charging battery

OK, looking at the pictures, that bloated cap (22uF 400VDC) in the primary side should be replaced for sure, the start-up/running cap and the output filter caps should also be replaced at the same time then see what happen. The SMPS is regulated power supply so it should be able to handle AC input from 90V~135V and keep the output Voltage constant.
BTW, check the DCV on the two legs of the output filter cap to see what you get.

[sambul83]

Re: APC Back-UPS 1300 not charging battery

Back to basics, the USP's still acting up. I didn't do the precise battery calibration test, but fully discharged it under 150W usual load: it took about 18min from 3-to-4 bars to Standby. So batteries aren't new, but they seems alive. I then borrowed a good working tested pack from a neighbor, and it shown the same issues with the UPS:

- won't charge the batteries if input voltage is below 118V. Batteries gradually discharge. External load doesn't have effect on it, if connected to utility

- draws utility power to power external load during discharge. It doesn't switch external load to battery power, unless detached from wall outlet

- goes to Standby mode if battery is disconnected. Goes back to Normal mode in 15min with battery disconnected, if utility voltage is above 118V

- assumption: the UPS raises charging voltage slowly as the battery charge increases. If utility drops below 118V, it can't raise charging voltage above battery voltage, so the battery isn't charged. Everything else seems to work OK: buttons, lights, alarms, LCD functions, relays switching sounds, programming, power switching, software

Attached some disassembly pics. The big cap C69 - 22 mF / 400V seems to have a bumped top. Any suggestions?

[sambul83]

Re: APC Back-UPS 1300 not charging battery

Some update... The UPS started discharging the battery again, LCD shows input voltage dropped to 117V, left 3 bars overnight at no load. The battery might not be charging since its voltage 28.3-28.9V at 70-100% charge is higher that charger voltage 27.8V at input 117V, which raises to 30.9V at input 118V. My another Back-UPS unit (works OK, different form factor battery pack) shown input 119V from the same outlet at that time - is that a normal error for these units?

Still unclear on the root cause of battery self discharge at a bit lower voltage contrary to the USP spec. Apparently, its a know issues, see XS 1000 Not charging?. Due to being so widespread it looks like a serious APC UPS hardware & software design flaw. Common user fed solution is Battery Runtime Calibration (see Daniel's last post) you also mentioned earlier. In my case the cause might be complemented by mild charging circuit components aging... if any.

Back-UPS Manual Runtime Calibration Procedure:

If you want to perform a manual runtime calibration or your UPS is an SU or older models, the steps are listed below:

1. Battery must be at 100% capacity when the Runtime Calibration is initiated/started.
2. The UPS must have at least a 30% load on it during the calibration.
3. The load cannot fluctuate more than +/- 5% during the calibration.
4. The battery must be discharged to at least 25% capacity (it is best to allow the UPS to shut off due to a discharged battery).

In addition to the above conditions, any UPS monitoring/shutdown software should be stopped from running in the background, and the serial cable should be detached from the UPS. This is necessary in order to prevent the software from shutting down the server/UPS due to an on-battery or low-battery condition.

Note: Before beginning the calibration make sure the UPS has been online and charging for at least 24 hours for just the UPS or 48 hours for a UPS with external batteries.

I found mentioning Procedure to Fully Reset a Back-UPS Microprocessor, a guy took lengthy notes from support about it, but lost. May be you came across such procedure on the web? It might involve running certain software utility.

[sambul83]

Re: APC Back-UPS 1300 not charging battery

I updated this post to mention the shutdown reason. The manual refers to Standby mode on page 3 under Sensitivity Adjustment. What is surprising, the power comes back eventually, but I guess it was requested by many users before. The UPS clearly shows fault by shutting down, and then comes back providing utility power. The only complaint is its done abruptly without warning despite utility power is still present, and is not controlled by PowerChute software. I may assume, they fixed these shortcomings in later models. Tomorrow I'll post an update, if reprogramming the UPS fixed the battery discharging & shutting down issue.

[budm]

Re: APC Back-UPS 1300 not charging battery

"Still may I ask, why charging voltage often gradually raising with UPS aging, and replacing what board components can usually fix that?" May be the regulation circuit has drifted and must be re calibrated, I do not if it is done through software or trimming pot.

[budm]

Re: APC Back-UPS 1300 not charging battery

"the UPS immediately switches to Standby mode" I did not see anything in the manual regarding standby mode, I would think if the AC is supplying the out to ALL the outlets when AC input is present (INVERTER circuit is OFF), then you disconnect the batteries, all it should do is to beep at you and not kill the power to the unit since there is no need to kill to power to the outlets if the incoming AC is still present, that is not good function.

[sambul83]

Re: APC Back-UPS 1300 not charging battery

Still may I ask, why charging voltage often gradually raising with UPS aging, and replacing what board components can usually fix that?

[sambul83]

Re: APC Back-UPS 1300 not charging battery

It can detect that there is no battery anymore, but not very gently. I'd say you can damage your hard drives easily in that case, or cause some OS & other files damage due to abrupt UPS shutdown, which is senseless since utility power is still present. I guess it protects APC from equipment damage claims by utility power spikes when batteries are off, since my unit switches to batteries in case of a spike. It doesn't have AVR, but other models do so their routing may differ.

[budm]

Re: APC Back-UPS 1300 not charging battery

Most UPS out there function the same way, at least your UPS can detect that the batteries are no longer connected or gone open circuit and warn you if the connection may have come off AFTER the unit has been running. Some other brand when I test the open battery connection test after the unit is running (AC power present, not in UPS mode), it will show me full batteries Voltage! which basically it is check the DC Voltage of the batteries but it actually seeing its own batteries charger circuit which is connected to the batteries terminal, same idea as your car, once the car started you can disconnect the batteries the car will still be running because the power source is coming from the alternator and if you do not have AMP meter to show if the batteries is being charged or if the battery is not present then you will not know that the battery is no longer there.
I really have no recommendation for the UPS.

[sambul83]

Re: APC Back-UPS 1300 not charging battery

If the battery is physically disconnected or fully depleted, the UPS immediately switches to Standby mode without any beep, meaning all equipment would abruptly shutdown without warning (in disconnect case) even if you run APC PowerChute on your PC and utility power is OK. That's what I faced. But... within 10-15 min the UPS would surprisingly turn back from Standby to Normal mode, and at that point I'd assume you can start your equipment hooked to battery outlets again, running on utility power with batteries disconnected. In fact that test I did with a small 1500W heater. The UPS will beep continuously, but can be shut up manually by controls.

It doesn't look like you like this unit that much. What brand & model in this power range would you recommend for home office use?

[budm]

Re: APC Back-UPS 1300 not charging battery

One thing I wonder about your unit is that once the UPS passed the self test and is supplying the AC to the loads, then you disconnect the batteries to simulate open cell (High impedance) batteries failure mode or battery connector came off, what will you see on the LCD panel and what will the UPS do?

[sambul83]

Re: APC Back-UPS 1300 not charging battery

If you put DC Amp meter in series with batteries then you can see if the current is being drawn from batteries or being fed into the batteries when UPS is not in Batteries Backup mode.

I assume if the battery is visibly discharging based on UPS LCD's readings, the current is drawn from it. APC support guy said their units are designed that way: if the battery isn't charging, it supplies power to PCB (but not to connected load) when UPS is hooked to outlet and on utility power, even at no load. I assume, the battery would stop discharging so fast, if one disconnects UPS from the wall outlet and load, and switches it off (if it can be switched off with batteries connected instead of dropping to Standby).

As to why the batteries don't blow up eventually due to continuous charging, I don't think APC 1st level support can answer such in-depth questions except saying "its by design", but may try to ask next time. Generally I'd expect ANY support troubleshooting call to APC inevitably end up with conclusion your UPS "upgrade" is long overdue.

[budm]

Re: APC Back-UPS 1300 not charging battery

BTW, I wonder what APC has to say about their batteries charging topology used in your UPS, what kind of protection does it have if the batteries are over heat, shorted cells, failed charging circuits, etc.

[budm]

Re: APC Back-UPS 1300 not charging battery

The charging is active 24/7 even when the UPS is not turned on, so it will keep charging the batteries as long as nothing goes wrong with batteries and the heat is dissipated, and local surround temperature is normal base on 25c.
Your ups is also line interactive type, meaning that the inverter circuit that converts the DC from batteries to AC will only run when the UPS detects the loss of incoming AC or when the line Voltage go below 90V or above 130V, the Voltage in that range is being regulated with the buck-boost switching tabs of the auto-transformer.
So basically the batteries is not really being used at all when the AC is normal.
The True-on line UPS, the inverter circuit is always running and there is no transfer time involve like the line interactive that the transfer relay has to kick in when it is on battery mode.
So just hope that the batteries does not go bad and cause real bad problem when it happen.
If you put DC Amp meter in series with batteries then you can see if the current is being drawn from batteries or being fed into the batteries when UPS is not in Batteries Backup mode.