If your source uninterruptible power supply for a computer that, after several years, no longer holds the load after turning off the power, then most likely its battery has failed. This is the most common breakdown of uninterruptible power supplies. The repair is extremely simple: replace the battery and forget about the problem for a few more years.
These types of batteries are not cheap. I suggest trying to restore the battery in a very simple way.
Theory
Why does the battery lose capacity and not hold a charge? One of the reasons for the failure of batteries of this type is the drying out of the cans. Therefore, we will just need to add a little distilled water to each compartment.
Battery recovery
I don’t want to give you false hope, but the method is not one hundred percent effective, since perhaps the battery has lost capacity not due to drying out. Although any recovery is not 100% guaranteed. Therefore, we will only give the battery a chance, which is definitely worth using, since it will not require significant effort from you, and if the restoration brings results, it will save you good money.
Diagnostics
We disassemble the uninterruptible power supply and remove the battery from it. We measure the voltage with a multimeter. If it is below 10 V, then the chances of restoring the battery are negligible, but they still exist.
For a dry battery, the voltage usually fluctuates around 13 V, and when a load is connected, it drops almost immediately.
In my case, everything is bad - 8 V in total.
Recovery process
These batteries are non-removable and are not intended for maintenance. Therefore, the compartments of the cans are sealed with a plastic lining, which must be pryed off with a sharp knife.
With a little skill, if you walk the tip around the perimeter, the plate will come off.
Underneath you can see six rubber caps for each compartment. These are kind of valves.
They are simply removed by hand. We remove them all and put them aside.
Next we need to find approximately 200 ml. distilled water. You can buy it at an auto store or very easily get it at home without special equipment - read how to do this in this article.
You will also need a syringe for 20 cc. And if there is no such thing, take any that is available.
Now everything is simple: add 15-20 ml to each compartment. distilled water. It’s difficult to say the exact amount, so we pour it into the compartment and look with a flashlight so that it’s almost to the top.
We go around all the banks.
If you wait a little, the water level will gradually decrease as the water is absorbed into the filler, which is located between the lead electrodes.
Close the holes with rubber plugs. We connect the charger and try to charge it. Of course, the battery can be immediately installed in the UPS, but who will know whether it will be charged there or not.
After an hour, turn it off and check the voltage. It has grown to almost 11 V. This means the battery is being restored.
We place the torn plastic cover on glue applied to the same places where the factory one was previously.
The battery is assembled.
We continue charging for another 3 hours. And a repeated measurement shows that the battery is charging.
This battery was about 5 years old. Of course, it didn’t immediately stop holding a charge, but sagged gradually. Now it has been brought back to life and has 80% of its original capacity. I think it will last a couple more years without problems, but who knows...
Here is the simplest method that will help bring you back to life old battery. Try it yourself, and you will always have time to throw out the battery.
Surely most of us use such a useful device as an Uninterruptible Power Supply (UPS). This device always comes to the rescue in situations where the electricity in the network is unexpectedly cut off, just at the moment when we are editing important documents, giving us about 15 more minutes of electricity to complete the work correctly. However, the UPS does not last forever and after a year or two, it begins to give us less and less time to complete work with the PC. And one fine day, when the electricity is cut off again, we leisurely save everything important documents Knowing that there are still about 10 minutes left, after a minute the uninterruptible power supply starts beeping frequently and turns off, leaving us bewildered.
Why does the UPS not work for the time specified in the specifications?
It's all about the battery, which powers the PC during a power outage in the external network. Unfortunately, the battery deteriorates over time and loses its capacity. Why does my battery drain quickly? There can be many reasons. Intensive use (overload) due to which sulfation of the plates begins. Incorrect charging mechanism - often batteries are constantly in recharging mode and the water that forms the basis of the electrolyte slowly evaporates, rendering the battery unusable.
Fortunately most common cause loss of battery capacity in the UPS is due to drying out of the electrolyte. Why fortunately? Because this can be corrected and the battery’s previous capacity can be restored.
You will need:
- Distilled water (not electrolyte!!!);
- Scotch;
- Syringe with a needle.
Remove the battery from the UPS.
We remove the cover and see something like this. Rubber caps that cover the openings of the cans. They probably serve to relieve excess pressure that is formed due to water vapor, hydrogen and other substances.
Remove the caps and pour distilled water into each jar. You need to make sure that the water does not flop around in the jar. When shining a flashlight into the holes, make sure not to pour excess water.
After filling, let's charge the battery (you can charge it using the uninterruptible power supply itself). If you overfill the water, excess water will flow out of the cans during charging. It needs to be collected and poured into the sewer.
After charging, I discharged the batteries a little with a car “carrying device”, about half an hour, measured the residual voltage, and estimated the capacity. I charged it again and discharged it a little again.
After these manipulations, we return the cover to its place and use tape to glue it to the battery body. We assemble the UPS.
Battery recovery results
In 10 minutes, under a load of 110VA, the batteries (in this case, there are two UPSs) were discharged to 79 percent. The program reported 29 minutes remaining until the end of the work. 29 + 10 (minutes already passed) = 40 minutes. Impressive result.
Based on materials from the site: habrahabr.ru
—> Near-computer —>
Restoring the battery in a UPS
I got an APC-420 uninterruptible power supply from the previous admin, it was all dirty, it was lying in the closet, among other rubbish. When I asked what was wrong with it, he said: “The battery is dead, if you need it, then order a new battery.” Okay, he's lying around and lying around, not asking to eat. Forgot.
About six months later, I accidentally came across him, during another fruitless attempt to restore at least some semblance of order in my sharaga. I connected it to the outlet in order to see what the uninterruptible power supplies with a dead battery say and show. He blinked the lights, beeped something, then they called me and took me away somewhere... In general, I found him again only a couple of months later. It stands peacefully, with a green light shining, saying that everything is in order with the voltage in the network. I unplugged it from the network, it got nervous, squeaked and hummed strainedly while continuing to supply voltage to a non-existent load :). After waiting 5 minutes for control, I turned it off and connected my computer through it. I tried how it behaves during a power failure - everything is clear, the computer plows, issues warnings (I slobbered it with a cable through the COM port), and after 7 minutes the computer turns off, followed by the UPS.
One day, the power was turned off without warning in advance. Nothing terrible happened. Almost everyone had UPS, completed the work and began to wait for it to be turned on. I didn’t cut anything down, I decided to check in “combat conditions” how long the equipment would last for self-powered. Along the way, it turned out that Cisco and the TAYNET DT-128 cable momet were connected directly to the network, without any filters or uninterruptible power supplies.
— After 8 minutes, my uninterruptible power supply died, without warnings, and Windows shutting down correctly. (This is despite the fact that I hesitated to select a cable for it - APC has at least two possible connections for COM cables)
— At the 15th minute, two sideboards, powered by one UPS at 700W, became dull.
— At the 15th minute, the proxy under FreeBSD, which had a small Back-UPS 475, died, and on this model there is basically no cable for communicating with the computer, so the work was not completed correctly.
— At the 22nd minute the power was turned on and the experiment ended. Three 24-port switches and a server powered by Smart-UPS 1500 remained in operation.
As a result, after some combinations and manipulations with rearranging UPSs, I got the 700th smart, and FreeBSD got mine, which seemed to be dead, but with an RS-232 interface (COM port) for pairing with a computer. He fought for a long time until he managed to get her to see him. The result of the last experiment was that everything ended correctly, but after turning on the power on the APC-420, the red light began to constantly light up, indicating that the battery had died:
The first thing that surprised me after disassembling the UPS was that the radiators on transistors were so small in size, I was used to old bass transistors with conventional transistors, but here I found field-effect ones - as a result, the size of the radiators was reduced by more than an order of magnitude:
The second thing that is considered good is the power of the transformer, which, judging by the markings on it, was equal to 430W, which is even more than the rated power of the uninterruptible power supply unit (there is an opinion that more powerful uninterruptible power supplies are also produced in such a case with minor differences in the circuit and more powerful key transistors):
Another interesting thing in the design that I hadn’t even noticed before is the ability to connect a network cable via Smart-UPS to additional protection. Upon closer examination, the circuit turned out to be quite simple, and only two pairs through which data is transmitted are protected (for the telephone pair, the protection is wired, but not wired):
To restore the functionality of the battery (12V 7.0Ah, the banks seem to be intact, none of them are swollen), a simple circuit was assembled for charging with an asymmetric current (I first discharged it to 10.8 volts with a 21W light bulb):
Charged up to 14.8 volts, after which it discharged again. And so three times. The charging current was about 0.5 A. The first time it discharged very quickly - literally in an hour. From the second run - for two and a few kopecks, the third time I didn’t discharge it, I put it in place. When his suffering was over, he worked like new. Of course, this didn’t make him new, but he worked for a long time. In a good way - three times is not enough, it was necessary to drive him away like that 5 times, he would have worked much longer (a year later a similar story happened to him, but I no longer worked there, and I don’t know how everything was resolved...).
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posted: 2005-10-04, |
The vast majority of us use this extremely useful device, as an uninterruptible power supply. The quality of food is not ideal everywhere, and it’s just the smallest problems with power supply can sometimes be expensive. Data loss is always unpleasant, and sometimes downright fatal. The device is purchased, installed under the table, connected, and its owner is fully confident that in any case, if there is a power outage, he will have time to correctly shut down the work, and maybe even make a backup to a flash drive. As time passes, the uninterruptible power supply periodically makes itself felt - like a real watchdog, it raises its voice at the slightest deviation in the parameters of the power grid. The owner is calm and everything is fine. But one day an outage does happen and this time the UPS does not just give a voice and immediately switches from the battery to the network, this time the lights were turned off for a long time. We are calmly copying files (after all, we have at least 15 minutes left) and then the uninterruptible power supply starts beeping very often and everything turns off. How so? After all, the uninterruptible power supply was supposed to protect us from such situations, but it only instilled in us false confidence in our safety! Why did it happen?
It's all about the batteries, from which our uninterruptible power supply feeds all our hardware when the external network is turned off. But these batteries, alas, do not last forever, they degrade, their capacity decreases, and with it the battery life. Down to zero. Unfortunately, this process is often not controlled by anyone, the owner is confident that he is protected, and at this time the battery is no longer really a battery, but a dummy.
What to do, what to do and where to run?
Why do batteries degrade? There are many reasons. Intensive use causes sulfation of the plates, overload causes the active substances to crumble, and so on. The UPS is maintenance free battery, but it still contains an electrolyte and this electrolyte is water based. Being constantly in buffer mode, in slow charging mode, the water gradually evaporates and the electrolyte no longer performs its functions. The battery becomes unusable. How can this be avoided? This can be avoided by using correct battery charging mechanisms and monitoring its characteristics, but all this is beyond our control - this is the lot of UPS manufacturers.
It so happened that the Internet in my area is only wireless; for its operation, a scary-looking antenna is installed on the roof, and to reduce signal loss in the cable, its length is minimized. The server that then distributes the Internet (another server and switch) is installed in the attic. This small bundle requires uninterrupted power. Even without taking into account data losses, running to load the server at the slightest sneeze (and here they happen often) is not much fun. There should be continuity and preferably more. I bought a 1100VA uninterruptible power supply, not new (new ones are more expensive than those servers) and of course I didn’t rely on batteries - they are often worn out. Well, I bought it and bought it. I installed it, everything seemed okay. The UPS control panel cheerfully told me about almost an hour of battery life (the load was about 70 VA). I decided to check it out. I turned off the power and after about two minutes everything turned off safely. Batteries are “dead”. This is exactly the case with false protection. There is nothing to do, you need to buy new batteries. I installed backup batteries (it just so happened that there are some from the electric bike and they are inactive), 12VA each. And he took his dead relatives downstairs.
I've heard that the electrolyte in UPS batteries often simply dries out. That it is not sulfation or chipping of the plates that causes the death of UPS batteries, but rather the drying out of the electrolyte. An attempt, as they say, is not torture. The batteries were about to be thrown away anyway, and the urge to pick didn’t give me a chance. To carry out the experiments I needed:
Distilled water (NOT an electrolyte!). Sold in an auto store.
- A syringe, better with a needle - with a needle it is easier to dose. Sold in a pharmacy.
- A knife for picking, stronger.
- Scotch tape for assembly (for aesthetes, of course, ONLY blue tape should be there!).
- Flashlight.
There is a cap glued to the battery that closes the cans. I carefully faked it with a knife (for picking). I had to go around in a circle - it was glued in several places.
Under the lid are jars covered with rubber caps. These caps are probably needed to release water vapor, hydrogen and other things that can create overpressure in the bank when the battery is running. It's like a nipple that lets gas out, but doesn't let anything in.
The caps are not glued, I just removed them by prying them off with a knife.
Under the caps, if you look inside the jar, there is nothing interesting. Absolutely. You need a flashlight to look.
I took a syringe, filled it with distilled water (The main thing is without dirt. So that everything is clean!) and poured a cube of water into each jar.
The water was safely absorbed, almost instantly. I repeated it again. Then again 5 or 7, I don’t remember. The water should not flop around in the jar, but it shouldn’t “take” the water from the jar either. It's better to shine a flashlight and take a look. The main thing is not to overfill.
After filling the water, I covered the jars with rubber lids and set the battery to charge. I charged it separately, with a large charger, but I think this is not necessary - you can simply charge it in an uninterruptible power supply. If the batteries are discharged below 10V, then it will not be possible to charge them in this way. There is information that such batteries can also be “boosted,” but to do this, it is necessary to apply high voltage to them at the initial stages (about 35V for a 12V battery) with current control. I haven’t tried it, so I can’t say anything specific. I also cannot recommend this method.
The first point is that if you overfill the water, it will return from under the lid. It must be collected with a syringe and poured into the sewer.
The second point is that if you cover the jars with lids, then during the charging process the pressure in the jar rises slightly and the lids will scatter throughout the room with a characteristic bang. It's funny, but only once. I checked twice - the second time is no longer fun. I covered the lids with the original plastic lid and placed a weight on it.
After charging, I discharged the batteries a little with a car “carrying device”, about half an hour, measured the residual voltage, and estimated the capacity. I charged it again and discharged it a little again.
I did the same with the second battery - there are a couple of them in the UPS. After all, I sealed the removed covers with tape and put the batteries in place.
The results are:
In 10 minutes with a load of 110VA, the batteries were discharged to 79 percent. The operating time on the battery varied somewhat, at the end the software said almost 29 minutes + 10 that had already passed, which comes out to almost 40 minutes. This state of affairs suits me. Enough to go and start the generator. When will I have it :). And make some tea along the way. And drink it.
Based on 79%, that's 21% in 10 minutes or 47 minutes of battery life. Somewhere in the region of what the software promises.
Another calculation option is the total capacity of batteries 12V * 7Ah * 2pcs = 168 Watt/hours. This is ideal. With a load of 110W, the charge should last for 1.5 hours. But in reality, even with new batteries there will not be such an operating time - the discharge current is too high and the delivered capacity will be lower. It is difficult to say for sure how much the capacity has been restored, but it is very likely that it is up to 80 percent of the nominal. In my opinion, it’s not bad at all for one syringe, a jar of distillate and an hour of time.
The moral of this story is:
- Check battery life periodically. They can screw you over at the most unpleasant moment.
- At your own peril and risk, even battered batteries can be restored with little effort. But no, you will always have time to buy new ones.
Article taken from geektimes.ru
Uninterruptible power supplies are undoubtedly a necessary addition to any workstation, and the battery is the main operating element of an uninterruptible power supply.
Unfortunately, the service life of uninterruptible power supply batteries is extremely short, and new batteries are very expensive. Let's look at how you can increase the life of your battery.
New battery life
From long work working fluid battery (sulfuric acid solution) gradually dries out, as a result of which the battery capacity tends to zero. The simplest and most effective method Extend battery life by monitoring the electrolyte level in the battery.
Naturally, you won’t do this all the time, but what to do when the battery no longer charges?
Battery recovery
We will need: distilled water, a syringe, a glass tube with a diameter of approximately 5mm, Charger from 0.05-1.5A.
Distilled water can be purchased at a pharmacy, auto store or the auto goods department of any supermarket. A syringe will be needed to dose water. The tube should preferably be glass, because... The plastic tube may react with the battery electrolyte. A charger from an old laptop will work as a charger if nothing more suitable is available.
The most common lead acid batteries Uninterruptible power supply units have a voltage of 12 Volts and a capacity of 7 AH. 12 Volts living conditions can be found in chargers for other battery devices, for example, a screwdriver. A 14-volt power supply is also suitable for charging, if there is no 12-volt one.
Recovery instructions
First you need to measure the electrolyte level. To do this, you need to remove the plugs on the top surface of the battery.
Batteries are widely used with two options for closing the plugs - with a common plug for all
or with an individual plug for each container.
First, use a flat-head screwdriver or knife to remove the plastic cover on the top of the battery.
Let's measure the electrolyte level
- Remove the rubber plug
- Insert a glass tube the size of a ballpoint pen into the hole. The tube should rest against the bottom.
- Close the top hole of the tube with your finger and pull it out
- The electrolyte level in the tube is equal to the level in the battery (the norm is 13-15 mm), if it is higher, then you should suck out the excess electrolyte with a syringe; if it is lower, it is time to add distilled water.
Add electrolyte
At this stage, you need to ensure that all battery cells are filled with electrolyte.
- We fill the syringe with clean water and add 5-10 ml into the battery cell until it is full.
- Repeat the operation for the remaining 5 battery cells
Battery boost
Take a special charger and connect it to the battery without closing the plug. This is necessary in case there is too much electrolyte, it will have somewhere to leak. First, charge and discharge the battery 3-4 times to restore capacity. Then set the current on the charging device to 0.1A and monitor the voltage at the terminals. Do not allow the battery to boil or overheat; if necessary, reduce charging current. Normal voltage at fully charged should be 13.9-14.5V. Next, reduce the current to 0.05A and continue charging. If the voltage remains unchanged over the next 2 hours, stop charging!
Get to work!
Close the lids. For greater reliability, leave the battery for about 12 hours. Then start using it. The battery is ready to go!