Maintaining UPS/car batteries

[dms664]

The Positive terminal of my second battery just changed its colour from silver to black and also the backup of my UPS got affected too.

When the batteries were new i was getting a backup of 2hours.

And now only 30mins from 2X140Amp Volta Batteries.

Please help.

1st Pic The terminal gone black in colour

2nd Pic the terminal of First Battery which is OK

3rd Pic the Positive terminal which gone black.

Check if you can smell rotten eggs odor in the vicinity of the batteries. if yes this is prolly acid on the terminal.
check the battery for leaks and always apply grease on the terminals.

Experts please correct me if I am wrong.

[car_bus2008]

What should be the voltage of a fully charged battery at rest.

Mine both batteries contain 12.5V after getting fully charged is it OK.

[humayunh]

Hey! Okay I know this is a stupid question, but in one cell of my UPS battery the acid level is just below the plates so a bit is exposed. Now is it safe to run it for 2-3 days like this or can I add Nestl? Water in it? =p or shall I only get those battery distilled water bottles from the store and add that hee?

[NakedTruth]

What should be the voltage of a fully charged battery at rest.

Mine both batteries contain 12.5V after getting fully charged is it OK.

12.7 is normal for new batteries. 12.5 is fine. No worries.

Hey! Okay I know this is a stupid question, but in one cell of my UPS battery the acid level is just below the plates so a bit is exposed. Now is it safe to run it for 2-3 days like this or can I add Nestl? Water in it? =p or shall I only get those battery distilled water bottles from the store and add that hee?

Add water PRONTO!.

[waqar19]

Using mercury 1000 watt and battery caps turned black within 1 month. Is it warning that battery is dying ?

[humayunh]

12.7 is normal for new batteries. 12.5 is fine. No worries.

Add water PRONTO!.

Nestl? water added! =P
Only one cell was below level, but I put a bit in all the cells just incase. For future reference, is adding normal water okay or shall I buy those distilled water bottles?

Secondly as the guy above me mentioned, does black stuff in the caps mean anything? I have 2 130amp batts running in series for my APC UPS. BackUp time has been fine, the batts are around 3-4 months old. But they have black stuff in the caps too..

[whiteangel]

Nestl? water added! =P
Only one cell was below level, but I put a bit in all the cells just incase. For future reference, is adding normal water okay or shall I buy those distilled water bottles?

Nestle water, tap water or any bottled water is not appropriate for adding to batteries because they contain high level of minerals. You need to add distilled water only.

I have a TDS gauge at home and it is useful for measuring dissolved minerals in water. Tap water in my area has a TDS between 300-500 ppm (parts per million) whereas Nestle water is around 250-350 (it is mentioned on the bottle). I also measured TDS of various battery waters available in the market and it is about 50 ppm.

Personally I use RO water from the filter in the home it has a TDS of 9-12 ppm. Distilled water should have 0 TDS and it is best for batteries.

[Automotorsport_Lover]

I must say that I have greatly benifited from this thread and it gave me the motivation to start doing stuff by my own!

Long story short - I upgraded to a 24 volt UPS from a 12 volt one in hope of getting better backup... Unluckily the whole thing went terribly wrong as we got an extremely pathetic UPS made by our electrician which kept blowing its transistors each day and evening!

Returned that UPS to him after having many sleepless nights! and never called him back again, now I have another electrician...

Now I have this UPS, purchased used from one of our relatives, it was working fine for the first few days but as the Ramadan started it started giving its buzzer alarms... After some useless calls to the electrician, worried & frustrated I decided to get a volt meter and investigate things by myself...

I got this Clamp meter for 565Rs. only...
At first I did not know how to operate it, but after reading user manual I figured it out and started monitoring the battery voltage... I observed that the battries were not retaining charge for long a fully charged battery at 24 volts on load, would fall down to 21 quite quickly... Even with 1 fan and energy saver only!

Hence the UPS buzzer was due to low battery power ( The UPS hasn't got its battery low light working ) I observed the charging amperes and figured out that the UPS was giving as much as 30 amperes for charging!!!! The battries would start showing 26 volts full almost instantly after wapda electricity was restored!!!

Then today I have lowered its charging from 30 amperes to 17 amperes max. Its still working pretty well, I mean i dont feel that its charging slow... i think it would still charge fully at 26 volts ( Cutt - off of this UPS ) within an hour.

Here are some pics..

MY UPS SET UP - 85 AMP-HR INTO 2 BATTRIES

BATTRIES AT 23 VOLTS

CHARGING CURRENT 16.7 AMPS

BATTRIES VOLTAGE STEADY IMPROVING, REACHED 25 V, CUT OFF @ 26V.

I hope that I well get good back up and battries will retain charge now... I was shocked to see 30 Amps charging current!! The UPS guy charges 500Rs per visit and this is his intellect level! Damn!! I think if this experiment proves successful then I should start this work myself
Thanks to this thread poster @talhawaleed

Please mention if I did any step wrong...

PS: For observation I have left my clamp meter connected and on... I hope continuous operation wont hurt it??

[Automotorsport_Lover]

Update:

It seems as if the battries still can't hold charge, my observation is that it falls from 24 to 21 volts very quickly And then 21-20 it takes time to drop....

I know that although these batteries were new, their specific gravity is low... I guess that's the cause of it loosing volts too quickly? It still charges to 26volts very quickly.... But then theres no good backup...

M thinking of buying a hydrometer and sulfuric acid... Plz guide me further ebt this...
@talhawaleed

Sent from my Sony Xperia U using PW Forums mobile app

[talhawaleed]

I must say that I have greatly benifited from this thread and it gave me the motivation to start doing stuff by my own!

Long story short - I upgraded to a 24 volt UPS from a 12 volt one in hope of getting better backup... Unluckily the whole thing went terribly wrong as we got an extremely pathetic UPS made by our electrician which kept blowing its transistors each day and evening!

Returned that UPS to him after having many sleepless nights! and never called him back again, now I have another electrician...

Now I have this UPS, purchased used from one of our relatives, it was working fine for the first few days but as the Ramadan started it started giving its buzzer alarms... After some useless calls to the electrician, worried & frustrated I decided to get a volt meter and investigate things by myself...

I got this Clamp meter for 565Rs. only...
At first I did not know how to operate it, but after reading user manual I figured it out and started monitoring the battery voltage... I observed that the battries were not retaining charge for long a fully charged battery at 24 volts on load, would fall down to 21 quite quickly... Even with 1 fan and energy saver only!

Hence the UPS buzzer was due to low battery power ( The UPS hasn't got its battery low light working ) I observed the charging amperes and figured out that the UPS was giving as much as 30 amperes for charging!!!! The battries would start showing 26 volts full almost instantly after wapda electricity was restored!!!

Then today I have lowered its charging from 30 amperes to 17 amperes max. Its still working pretty well, I mean i dont feel that its charging slow... i think it would still charge fully at 26 volts ( Cutt - off of this UPS ) within an hour.

Here are some pics..

MY UPS SET UP - 85 AMP-HR INTO 2 BATTRIES

BATTRIES AT 23 VOLTS

CHARGING CURRENT 16.7 AMPS

BATTRIES VOLTAGE STEADY IMPROVING, REACHED 25 V, CUT OFF @ 26V.



I hope that I well get good back up and battries will retain charge now... I was shocked to see 30 Amps charging current!! The UPS guy charges 500Rs per visit and this is his intellect level! Damn!! I think if this experiment proves successful then I should start this work myself
Thanks to this thread poster @talhawaleed

Please mention if I did any step wrong...

PS: For observation I have left my clamp meter connected and on... I hope continuous operation wont hurt it??

Great, you are benefiting from this thread now kindly correct the followings on your UPS

1. Cutoff Voltage should be set at 28 Volts not 26 Volts. This is the Voltage once UPS should stop charging the batteries and Voltage after once charging will stop will drop to around 25 Volts, don’t worry about that. Adjust this ….
2. I see, you have attached GL85 batteries with this UPS system, so roughly the AMP HR rating would be around 85 AMP-HR. Now, I know that you have two of these batteries in parallel but even then you cannot allow more then 8.5 AMP of current to pass through it. Adjust the charging rate to 8-9 Amperes and I can guarantee that your backup time will be even better.

Formula for charging current is AMP-HR ratings/10

[talhawaleed]

Update:

It seems as if the battries still can't hold charge, my observation is that it falls from 24 to 21 volts very quickly And then 21-20 it takes time to drop....

I know that although these batteries were new, their specific gravity is low... I guess that's the cause of it loosing volts too quickly? It still charges to 26volts very quickly.... But then theres no good backup...

M thinking of buying a hydrometer and sulfuric acid... Plz guide me further ebt this...
@talhawaleed

Sent from my Sony Xperia U using PW Forums mobile app

Once, you will adjust the cutoff Voltage to 28 Volts and reduce the charging rate to 8 to 9 Amperes, then problems as highlighted by you will be automatically corrected. Specific gravity is down because your cutoff is not set up properly, which means that batteries are not being charged to its level (it is not even close) and since charging rate currently is so high that it kicks the voltage across terminals to 26 volts quickly ( FAKING IT). Rest under current circumstances, this behavior as highlighted by you is obvious and if it will continue like this then batteries won’t last for longer. Correct the problem …

[Automotorsport_Lover]

Once, you will adjust the cutoff Voltage to 28 Volts and reduce the charging rate to 8 to 9 Amperes, then problems as highlighted by you will be automatically corrected. Specific gravity is down because your cutoff is not set up properly, which means that batteries are not being charged to its level (it is not even close) and since charging rate currently is so high that it kicks the voltage across terminals to 26 volts quickly ( FAKING IT). Rest under current circumstances, this behavior as highlighted by you is obvious and if it will continue like this then batteries won’t last for longer. Correct the problem …

Yes I have discovered some problem with the battries after monitoring them... I took them to the battery shop and one cell out of 12 had negative gravity according to the battery wala guy... that has been given for repair/replacment... This was the reason that the charge was not increasing from 26volts and i thought it was the cutt off, I talked to the electrician too and he said that the cutt off was 28 volts...

Now once the battery is recieved I will adjust the current as directed by you and then inform you thanks.

[dms664]

Great, you are benefiting from this thread now kindly correct the followings on your UPS

[LIST=1]
[*]Cutoff Voltage should be set at 28 Volts not 26 Volts. This is the Voltage once UPS should stop charging the batteries and Voltage after once charging will stop will drop to around 25 Volts, don’t worry about that. Adjust this ….
[*]I see, you have attached GL85 batteries with this UPS system, so roughly the AMP HR rating would be around 85 AMP-HR. Now, I know that you have two of these batteries in parallel but even then you cannot allow more then 8.5 AMP of current to pass through it. Adjust the charging rate to 8-9 Amperes and I can guarantee that your backup time will be even better.
[/LIST]

Formula for charging current is AMP-HR ratings/10

Sir what is the relation of charging rate and backup time?

[Automotorsport_Lover]

Sir what is the relation of charging rate and backup time?

Sulphate deposits on battery plates and it impairs its capability to store charge for long... The battery expires quickly

With slow charging the sulfuric acid in the electrolyte remains mixed in the water... Not sticking to the plates...

Sent from my Sony Xperia U using PW Forums mobile app

[talhawaleed]

Sir what is the relation of charging rate and backup time?

Slow charging is good for batteries, prolongs the life and in-return you can harvest the maximum. Concept slow charging and fast charging is entirely dependent upon the AMP-HR ratings of your batteries. Like formula says that maximum allowable charging rate is AMP-HR ratings/10 which in your case turn around to be 8.5 Ampere. Anything between 3-5 Amperes will be considered as slow charging in your case but we need this value to be set at its maximum allowable limit such as 8.5 Amperes because of intensity of load shedding in Pakistan so that batteries be fully charged before the next cycle of load shedding.

Anything above 8.5 Amperes in your scenario is not recommended and this will kill the batteries much earlier.

[whiteangel]

^ While adjusting the charging rate one thing that everyone should keep in mind is not to be confused by the number printed on the battery case. So for example is the battery is labelled as NS 200Z, don't assume it is a 200AH battery. Battery manufacturers have started labeling batteries with higher numbers just to fool the consumer while the actual AH rating is quite less.

Always consult the battery specifications to know the correct AH and adjust charging rate accordingly.

[Automotorsport_Lover]

@talhawaleed

1. Where can I get Hydrometer? Im in LHR

2. Where can I get Distilled water in large quanitity?

3. How much Distilled water maybe required for 2 x 85 AMP battries?

4. From where can i get sulphuric acid?

[talhawaleed]

see, answers

@talhawaleed

1. Where can I get Hydrometer? Im in LHR : From any battery shop

2. Where can I get Distilled water in large quanitity: Contact pryochemicals, they are based in Lahore and buy electrolyte of 1250 gravity from them. you will escape from trouble of preparing the electrolyte.

3. How much Distilled water maybe required for 2 x 85 AMP battries?

4. From where can i get sulphuric acid?

[whiteangel]

@talhawaleed

1. Where can I get Hydrometer? Im in LHR

2. Where can I get Distilled water in large quanitity?

3. How much Distilled water maybe required for 2 x 85 AMP battries?

4. From where can i get sulphuric acid?

If you want to save the hassle, then you can simply order bulk electrolyte (30kg) from Pyro Chemicals in bank square, model town. But if you want to do it yourself, then for all the above you can pay a visit to Urdu bazar. There is a street adjacent to Urdu bazar which has several vendors dealing in laboratory equipment. You can get hydrometers and distilled water in 5 litre bottles. But they only sell lab grade sulphuric acid, which is expensive.

[saadzzz]

U can find hydrometer easily if u live in or near by model town in A block store market there are a lot of Battery shops and spare parts shop. I my self purchased hydrometer from a spare part shop...