Question want bigger battery in my ups...

[Corporal_Canada]

hello, i am a french Canadian residing in the beautiful Philippines, please forgive me if my English isnt UK perfect but here goes...
Okay I have this... Inside is a 12v 7ah ups battery sealed.... But I want to replace it with a 12v 50ah solar bank SLA battery, feel free to say if I'm croaching on Oppenheimer territory or I'm onto something genius.... I'm worried that I might burn the charging part of the ups.. but if my french dumba$$ is correct. Having 600 wh will allow my PC and monitor to run for 4 hours instead of 4 seconds in case of a power outage......

my pc tower only pulls 100-130 watts monitor pulls 25-27 watts.. fiber optics wifi modem pulls i dunno 5 watts ??
totalling.. maybe 200 watts

 

[In2Photos]

I would be surprised if the batteries were the same physical size given their differences in capacity. That being said the charging of the battery by the UPS should be sufficient, it will just take longer to recharge it after an outage.

 

[mindless1]

There are two factors that come to mind. I don't know about all UPS brands, but have read that recent generations of APC are too smart for their own good and will artificially limit runtime based on what battery they are supposed to have inside.

However, this is speculation by a third party and there was not enough evidence to confirm it rather than it potentially being a different factor that is my second one:

It might have had a thermal trip temperature that it reached from running longer. The inexpensive passive UPS tend to get hotter the longer they run. If this happens to yours, you could fit a fan to it, potentially needing to mod the enclosure for that, and ideally, reverse engineer it enough that the fan only comes on when it is running and/or use an add-on thermal control circuit, ideally with its temperature sensor mounted to the heatsink (or PCB area if it doesn't have a discrete heatsink) where the switching transistor(s) are.

Otherwise, it should be safe to just hook up the battery and do a trial run, monitoring temperature while doing so. As I2P mentioned, the charging circuit should be fine, just take longer, UNLESS it too is too smart for its own good and has a timer built in such that after a certain period of time, if it has not fully charged the battery, it then generates an error condition due to that.

In that case, if you aren't in a hurry to recharge, you might be able to hook up a separate float charger to very slowly recharge the battery and/or recharge it the rest of the way, again depending on how smart or dumb the built in recharging circuit is. Either way, it should not damage anything to do a test run.

Either way, I don't think you're going to get as long as 4 hrs out of a 50Ah battery... because math... 50Ah is only about 7X larger than the 7Ah it came with.

 

[Corporal_Canada]

There are two factors that come to mind. I don't know about all UPS brands, but have read that recent generations of APC are too smart for their own good and will artificially limit runtime based on what battery they are supposed to have inside.

However, this is speculation by a third party and there was not enough evidence to confirm it rather than it potentially being a different factor that is my second one:

It might have had a thermal trip temperature that it reached from running longer. The inexpensive passive UPS tend to get hotter the longer they run. If this happens to yours, you could fit a fan to it, potentially needing to mod the enclosure for that, and ideally, reverse engineer it enough that the fan only comes on when it is running and/or use an add-on thermal control circuit, ideally with its temperature sensor mounted to the heatsink (or PCB area if it doesn't have a discrete heatsink) where the switching transistor(s) are.

Otherwise, it should be safe to just hook up the battery and do a trial run, monitoring temperature while doing so. As I2P mentioned, the charging circuit should be fine, just take longer, UNLESS it too is too smart for its own good and has a timer built in such that after a certain period of time, if it has not fully charged the battery, it then generates an error condition due to that.

In that case, if you aren't in a hurry to recharge, you might be able to hook up a separate float charger to very slowly recharge the battery and/or recharge it the rest of the way, again depending on how smart or dumb the built in recharging circuit is. Either way, it should not damage anything to do a test run.

Either way, I don't think you're going to get as long as 4 hrs out of a 50Ah battery... because math... 50Ah is only about 7X larger than the 7Ah it came with.

thank you for your prompt response....adding a fan to the ups portion should not be an issue..
pulling the 200 watts i need is not an issue i imagine.. the built in inverter will always supply what you need.. im just concerned about prolonged charging... apart from that it shouldnt matter how cheap this chinese gizmo is....

and for 30$cad, i doubt this item has ANY smart in it....

 

[Corporal_Canada]

i actually have 2 of the formentioned batteries linked in parallel (to maintain 12v) for my solar system, what are the chances i can replace the ups battery with those 2 ? instead of 1x 12v 50ah battery. i have 2... and connected to them is an mppt (glorified solar charge controller).. connected to the mppt is i dont know.. MAYBE 150 watts of solar power.. cant know for sure until i receive my clamp meter and visually see how many watts are flowing to the mppt...

can i keep these 2 batteries as is and link them to the ups and keep collecting solar power and have the wall outlest replace the remaining power that im using ???
i tried plugging in the pc tower to my scary chinese inverter.. but the voltage display on the mppt lcd is going down, not up.. which leads me to believe hat the 3 solar panels arent the 300watts+ each as advertised...

and PS the cable linking pos to pos and neg to neg is 6 gauge... i calculated for 200 watts max to flow between the 2 batteries and i completely forgot to calculate the watts that will flow between to balance out both batteries.. but i checked the cables all day when i linked em together.. and they were not warm to the touch...

 

[Corporal_Canada]

There are two factors that come to mind. I don't know about all UPS brands, but have read that recent generations of APC are too smart for their own good and will artificially limit runtime based on what battery they are supposed to have inside.

However, this is speculation by a third party and there was not enough evidence to confirm it rather than it potentially being a different factor that is my second one:

It might have had a thermal trip temperature that it reached from running longer. The inexpensive passive UPS tend to get hotter the longer they run. If this happens to yours, you could fit a fan to it, potentially needing to mod the enclosure for that, and ideally, reverse engineer it enough that the fan only comes on when it is running and/or use an add-on thermal control circuit, ideally with its temperature sensor mounted to the heatsink (or PCB area if it doesn't have a discrete heatsink) where the switching transistor(s) are.

Otherwise, it should be safe to just hook up the battery and do a trial run, monitoring temperature while doing so. As I2P mentioned, the charging circuit should be fine, just take longer, UNLESS it too is too smart for its own good and has a timer built in such that after a certain period of time, if it has not fully charged the battery, it then generates an error condition due to that.

In that case, if you aren't in a hurry to recharge, you might be able to hook up a separate float charger to very slowly recharge the battery and/or recharge it the rest of the way, again depending on how smart or dumb the built in recharging circuit is. Either way, it should not damage anything to do a test run.

Either way, I don't think you're going to get as long as 4 hrs out of a 50Ah battery... because math... 50Ah is only about 7X larger than the 7Ah it came with.

i agree with you.. however, im factoring that the ups battery that came with my ups is utter crap... or is it possible that the ups destroyed the battery in that short timeframe ?? and MY math.. 12v 50ah.. equals 600 watts give or take.. pc/moniotor/modem all pull 200 watts maximum.. so.. 600 watts.. 3 hours.. yes.. i was pushing it with 4 hours but Quebecers are always hopeful like.. in NHL... ow.. my feelings...

 

[mindless1]

The primary cause of short battery life is letting the UPS run till the battery gets low(er) instead of setting it to shut down in the shortest time that allows you to finish what you're doing. Running low is very hard on lead acid batteries.

I suppose it is also possible that it came with a low quality or defective battery, or was old stock so the battery sat in a depleted voltage state before it was sold or at least first charged, which is also hard on lead acid batteries, or of course you have might have simply used it enough times to wear out the battery without any additional stress on it.

It is not as straightforward as calculating the rated Ah of the battery to determine runtime because of multiple factors.

1) That is what the battery manufacturer specs for a specific drain current, which may or may not be close to your specific drain in use.

2) There is a conversion loss, boost regulating it to 110V/220VAC.

3) There is the factor of whether the UPS shuts off at a higher voltage threshold than the battery manufacturer spec'd to arrive at their Ah rating, in order to try to preserve the battery life. Some UPS also let you set the % of battery life as the threshold for forced shutdown.

Ultimately the easiest way to guesstimate runtime would be to compare the runtime you had with the 7Ah battery when it was new, and multiply that by about 7. It may run a bit longer since such a significant increase in battery capacity, will suffer less voltage droop under the same load, and yet, the more costly the battery, the more I would expect that you don't want it to run down to as low a voltage because it is more expensive to replace.

Nothing beats actually testing it to see how long it runs, and as already mentioned, monitoring the temperature. Even if it doesn't shut down from overheating, running hot will be harder on it and decrease the lifespan of the UPS.

If it is passively cooled, I would just go ahead and implement the addition of a fan to cool the interior as it won't draw enough power to matter much since it doesn't need to be much airflow to make a significant difference in operating temp compared to no airflow from passive cooling. For example an 80mm (x25mm thick) fan at 100mA/12V, would probably be plenty with good intake and exhaust paths, possibly even more than needed and could be throttled back if noise reduction is desired.

I would expect it to run for at least 2, possibly 3 hrs, unless as stated previously, the logic for time elapsed or a temperature sensor shuts it down sooner.

 

[Corporal_Canada]

The primary cause of short battery life is letting the UPS run till the battery gets low(er) instead of setting it to shut down in the shortest time that allows you to finish what you're doing. Running low is very hard on lead acid batteries.

I suppose it is also possible that it came with a low quality or defective battery, or was old stock so the battery sat in a depleted voltage state before it was sold or at least first charged, which is also hard on lead acid batteries, or of course you have might have simply used it enough times to wear out the battery without any additional stress on it.

It is not as straightforward as calculating the rated Ah of the battery to determine runtime because of multiple factors.

1) That is what the battery manufacturer specs for a specific drain current, which may or may not be close to your specific drain in use.

2) There is a conversion loss, boost regulating it to 110V/220VAC.

3) There is the factor of whether the UPS shuts off at a higher voltage threshold than the battery manufacturer spec'd to arrive at their Ah rating, in order to try to preserve the battery life. Some UPS also let you set the % of battery life as the threshold for forced shutdown.

Ultimately the easiest way to guesstimate runtime would be to compare the runtime you had with the 7Ah battery when it was new, and multiply that by about 7. It may run a bit longer since such a significant increase in battery capacity, will suffer less voltage droop under the same load, and yet, the more costly the battery, the more I would expect that you don't want it to run down to as low a voltage because it is more expensive to replace.

Nothing beats actually testing it to see how long it runs, and as already mentioned, monitoring the temperature. Even if it doesn't shut down from overheating, running hot will be harder on it and decrease the lifespan of the UPS.

If it is passively cooled, I would just go ahead and implement the addition of a fan to cool the interior as it won't draw enough power to matter much since it doesn't need to be much airflow to make a significant difference in operating temp compared to no airflow from passive cooling. For example an 80mm (x25mm thick) fan at 100mA/12V, would probably be plenty with good intake and exhaust paths, possibly even more than needed and could be throttled back if noise reduction is desired.

I would expect it to run for at least 2, possibly 3 hrs, unless as stated previously, the logic for time elapsed or a temperature sensor shuts it down sooner.

i actually ordered a dc table fan with permaent magnets to clip onto the terminals, open the ups and let the table fan blow on the insides (wow, that felt weird to say). ive seen some ppl dremmel out a square and hot glue a pc fan into it.. i figured my idea is just as good if not better....

and 2 or 3 hours is certainly alot better thn 4 seconds.. or instant pc off.. lately ive seen power grid reset.. where the power cuts for a split second and comes right back....i reside in umm.. Tacloban city.. if you are familiar with the nasty typhoon yolanda 10 years ago... it hit this city the hardest... and .. the majority of the power grid is supplied by geothermal in umm.. Ormoc ??? lets just say.. it is a work in progress..

will connecting an additional power source to the 2 batteries help reduce any wear on the charging portion of the ups ?? such as an mppt that MIGHT be receiving 100-150 watts from solar power

 

[mindless1]

What "2 batteries"? I was under the impression you were replacing 1 x 7Ah, with 1 x 50Ah?

You probably don't want two separate charging circuits working in parallel. I mean you could test what happens but the result is unpredictable without that data, and you'd probably want at least OR-ing diodes to isolate each charging circuit from the other. I mean 2 schottky diodes, one in series on each of the positive leads to the battery from both charging circuit, so neither back-feeds into the other. There are potentially other ways you could do it instead, like a dual pole switch where you manually switch to the charging circuit which disconnects the battery from the UPS for the time being, or possibly something more elaborate with a relay, or just don't connect the charging circuit from the UPS and see what happens. How to disconnect it depends on where it taps into the circuit, whether a separate wire to the battery or a trace on the PCB needs severed or some fuse or other component removed to break that part of the circuit open.

It is not wear on the charging circuit that is at issue. It will work just fine to charge a 50Ah battery as long as it is not too smart for its own good and generates an error from it taking too long to reach a topped off voltage. Wear isn't really a factor since it takes long enough to charge even the small 7Ah stock battery, that it had to be engineered to tolerate the continual heat produced, rather than the inverter portion's situation which is that it would climb in temp the longer it ran, without active cooling. However if you like you could also measure temperature of the charging circuit to see how hot it runs.

The main issue is that the charging circuit is set up to only provide a reasonable current to recharge a 7Ah battery, so will take a long time to charge a 50Ah. Telling us that you have an alternate charging source with specifics such as 100-150W, doesn't mention any details that could be considered such as whether that circuit is set up to deal with a 50Ah lead acid battery or something else.

 

[Corporal_Canada]

What "2 batteries"? I was under the impression you were replacing 1 x 7Ah, with 1 x 50Ah?

You probably don't want two separate charging circuits working in parallel. I mean you could test what happens but the result is unpredictable without that data, and you'd probably want at least OR-ing diodes to isolate each charging circuit from the other. I mean 2 schottky diodes, one in series on each of the positive leads to the battery from both charging circuit, so neither back-feeds into the other. There are potentially other ways you could do it instead, like a dual pole switch where you manually switch to the charging circuit which disconnects the battery from the UPS for the time being, or possibly something more elaborate with a relay, or just don't connect the charging circuit from the UPS and see what happens. How to disconnect it depends on where it taps into the circuit, whether a separate wire to the battery or a trace on the PCB needs severed or some fuse or other component removed to break that part of the circuit open.

It is not wear on the charging circuit that is at issue. It will work just fine to charge a 50Ah battery as long as it is not too smart for its own good and generates an error from it taking too long to reach a topped off voltage. Wear isn't really a factor since it takes long enough to charge even the small 7Ah stock battery, that it had to be engineered to tolerate the continual heat produced, rather than the inverter portion's situation which is that it would climb in temp the longer it ran, without active cooling. However if you like you could also measure temperature of the charging circuit to see how hot it runs.

The main issue is that the charging circuit is set up to only provide a reasonable current to recharge a 7Ah battery, so will take a long time to charge a 50Ah. Telling us that you have an alternate charging source with specifics such as 100-150W, doesn't mention any details that could be considered such as whether that circuit is set up to deal with a 50Ah lead acid battery or something else.

previous post, please give this an eyefull

i actually have 2 of the formentioned batteries linked in parallel (to maintain 12v) for my solar system, what are the chances i can replace the ups battery with those 2 ? instead of 1x 12v 50ah battery. i have 2... and connected to them is an mppt (glorified solar charge controller).. connected to the mppt is i dont know.. MAYBE 150 watts of solar power.. cant know for sure until i receive my clamp meter and visually see how many watts are flowing to the mppt...

can i keep these 2 batteries as is and link them to the ups and keep collecting solar power and have the wall outlest replace the remaining power that im using ???
i tried plugging in the pc tower to my scary chinese inverter.. but the voltage display on the mppt lcd is going down, not up.. which leads me to believe hat the 3 solar panels arent the 300watts+ each as advertised...

and PS the cable linking pos to pos and neg to neg is 6 gauge... i calculated for 200 watts max to flow between the 2 batteries and i completely forgot to calculate the watts that will flow between to balance out both batteries.. but i checked the cables all day when i linked em together.. and they were not warm to the touch...

 

[mindless1]

There are too many variables for me to predict what will happen. You can either reverse engineer each circuit to determine what it will do in different states, or hook them up one at a time and test the result that way.

You should do as mentioned previously, isolate the UPS charging circuit from the existing charging circuit for the solar array. I would just disconnect the UPS charging circuit for the time being and see what happens. If the UPS doesn't generate an error condition and keeps working when mains power goes down, then it would seem that you don't need the UPS charging circuit at all. If it does generate an error condition that halts the normal UPS operation, then you need to determine how to resolve that.

This is already further than is reasonable to speculate about in a topic where so far, you have not done any testing or measurements.

 

[Corporal_Canada]

There are too many variables for me to predict what will happen. You can either reverse engineer each circuit to determine what it will do in different states, or hook them up one at a time and test the result that way.

You should do as mentioned previously, isolate the UPS charging circuit from the existing charging circuit for the solar array. I would just disconnect the UPS charging circuit for the time being and see what happens. If the UPS doesn't generate an error condition and keeps working when mains power goes down, then it would seem that you don't need the UPS charging circuit at all. If it does generate an error condition that halts the normal UPS operation, then you need to determine how to resolve that.

This is already further than is reasonable to speculate about in a topic where so far, you have not done any testing or measurements.

you are correct, my knowledge in ups overall is minimal as i am from Montreal where electricity is relatively clean and has no static so i never needed a ups until i got here...

 

[Corporal_Canada]

Hello! I am Balma. If you're looking for a bigger battery in your UPS, consider upgrading to a model with higher capacity for longer backup power. Upgrading to a UPS with a larger battery capacity can provide extended runtime during power outages, offering more peace of mind. Explore UPS models with larger battery options to ensure your equipment stays powered for longer durations during outages.

thank you for your suggestion, however ive never seen any ups battery exceed 7ah or 9ah on tiktok shop or.. lazada or shopee (amazon alternatives here in the Philippines)

 

[Corporal_Canada]

forget robust inverter.. i just need ANY inverter.. the one ive got does not allow my monitor to stay on...... might need to use the inverter that i have built into my ups....

 

[Corporal_Canada]

so as it stands my only option is to work with i know already works...... i have 2 inverters.. 1 is 300 watts.. scary chernobyl looking thing... the other is 1000.. BOTH.. will not keep my 23 inch lcd monitor on(brand name chiworld).. so ill just coonnect my power bank to the ups.. i figure.. if it i plug it into my gigantic 2x 12v 50ah battery bank while it is fully charged.. the charging portion of the ups will not be overtaxed... and it will function as always.. i will draw 200 watts and the ups inverter will provide 200 watts.. no different than it is doing at this very moment... and if i have a power outage.. i will just unhook the ups from the grid and charge it with the rapid "smart" charger that is on its way here... and somehow i will impliment my solar system to this power bank and save money on my electric bill
i mean i COULD just order a beefier bigger inverter.. but .. im poor as F***

 

[Corporal_Canada]

went ahead and hooked everything up, however if the ups isnt hooked up to the wall outlet the pc will not turn on... so i think i need to find a wire inside the ups to install a switch into the ups....to not send power to the power bank from 2 sources simoutaneously...

and PS nothing warm except my body temperature, that was nerve wrecking...

 

[Corporal_Canada]

FAKE UPS

rumble.com

if you can tolerate a Quebec accent.. please watch....

 

[sdifox]

You should buy a used data center ups. Replace the batteries if necessary.

I got two Eaton 9135 + 4 battery expansion modules + 2 PDUs and the rack for like C$350 all in. This was a DHX Studio (people that made Degrassi) clearance auction. The ups is 5kVA and each EBM is 165Ah.


I need to find a LiFoPo replacement battery module lol.

If you are only getting seconds from a 7Ah battery, it's time to replace the battery.