UPS Problems

hey guys i am new to this forum. lets get to the topic. i have 2 Aurora 600 watt pure sine wave ups with 165 Amp battery to each one. how much backup should they give once full charged? on long loadshedding, load is 1 fan 2 lights on each UPS.

plus, how can i get to know that the batteries are fully charged? i am really concerned regarding UPS as loadshedding has become a major headache in Pakistan :(

any help would be highly apprecciated :)

P.S--> the loadshedding schedule here is 2 hours wapda then 1 hour UPS

sometimes wapda goes for a long time like 6-8 hours due to fault in main plant or something

please reply...

Keeping it simple...

Calculate your load in WH

Calculate energy stored in your batteries @ 12V

Calculate the time in hours

I haven't used a aurora UPS, I believe it is one with a display. You can check the Battery Stat of charge (SOC) from it's display.

But your specs seems to be bit off, e.g I haven't seen a 12V pure sine wave ups, usually pure sine wave are at-least 24V (2 batteries) systems.

You should be fine with that ups if the load is just 1 fan, on a side note a 24v system on 2fans+4lights would be much more efficient.

Yousaf: there are a number of pure sine wave inverters now a days that run on 12v but they cost as much as 20-30k so most people don't think it as a viable investment.

thanx for the reply guys. still i didnt get answered about the question that how much time do they need to get fully charged? now mine is a pure sine wave 12V system with one AGS battery. right now it gives a backup of 6 hrs with 1 fan 2 lights (LED) in long loadshedding.is that fine or should it give more backup? battery water is mantained regularly.

P.S-->do i need to prevent overheating of the ups?

[quote=“djayz, post:3, topic:21244”]

You should be fine with that ups if the load is just 1 fan, on a side note a 24v system on 2fans+4lights would be much more efficient.

Yousaf: there are a number of pure sine wave inverters now a days that run on 12v but they cost as much as 20-30k so most people don't think it as a viable investment.

[/quote]

12V pure sine wave inverter are too inefficient IMHO.

Edited.

why u no answer my question guys!!! how much time do they need to get charged and do i need to prevent overheating??

[quote=“umaid111, post:6, topic:21244”]

why u no answer my question guys!!! how much time do they need to get charged and do i need to prevent overheating??

[/quote]

The time needed to fully charge a battery depends upon many factors, some of them are as follows:

1) Charging current of the charger (unknown in your case)

2) Ambient temperature

3) Condition of battery/cells (gravity of the electrolyte, again unknown)

For a 165AH battery, assuming your charger can provide 6Amp of current, it will take about 30 hours to fully charge a fully discharged 165AH battery.

If the output voltage of charger is not sufficient (no matter how many amperes it can deliver), it will never be able to fully charge the battery. Also during these days of peak load shedding, I doubt if your battery will ever fully charge. Keep the load at minimum while UPS is on battery.

I have seen the chargers of the UPS burning out while trying to charge a fully drained battery. Thus if your UPS has a built-in fan, you don't need to add anything external. However it is always a good practice to install UPS at some place where there is good air flow.

Pure sine wave in general are very inefficient , it is a complex system and efficiencies drop at every step in conversion and in this case upto 50% overall but there are a few decent APC's that are ridiculously efficient, so its totally upto the system.

@OP: Your battery may take 50 hours for all we know.

You should read all the above suggestions aswell , the fact that the charge rate is instantaneous in CV mode, and the charger runs both CC, CV and in some cases Float charge mode one can speculate the total time for what its worth you probably need a buttload of instantaneous readings and calculations , which again is something you didnot provide and you should not expect everyone to spoonfeed you.

P.S: A problem well stated is a problem half solved.

dude that is like hell man. my UPS takes 8 hours to charge a fully drained battery. charging voltage is 13V. u are telling the time too long.it can charge a fully drained 2 year old battery in this time. i dun know what you are talking about.WHEW!

Djyaz u are just being rude :P

[quote=“umaid111, post:9, topic:21244”]

dude that is like hell man. my UPS takes 8 hours to charge a fully drained battery. charging voltage is 13V. u are telling the time too long.it can charge a fully drained 2 year old battery in this time. i dun know what you are talking about.WHEW!

Djyaz u are just being rude :P

[/quote]

Nobody is being rude. Just as @Ijaz Ahmed mentioned, battery charging depends on a lot of variables. As @djayz mentioned a battery goes through a complete charging cycle (if allowed to do so). It depends on the charger if it's 3 stage or 4 stage charging cycle.

For more info please do read http://www.trojanbattery.com/BatteryMaintenance/Charging.aspx

http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery

http://batteryuniversity.com/learn/article/what_is_the_c_rate

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@umair

first of all, let us clear some problems for you.

1 - your UPS is NOT PURE SINE wave.. no matter how many times you write PURE sine wave, its not..its modified sine wave.

2 - there are 12V and 24V ups.. work with one battery or 2 battery.. 24V are much superior and possible more pure sine wave than 12V.. 24v do better faster charging, and better battery current supply

3 - there are multiple things that could effect the charging of your battery

  • your ups is poor quality
  • your ups has low charging capability
  • your battery is too old
  • one of the cells of your battery is faulty or dead.
  • your wapda voltage in your area is low
  • your ups is too small in capacity to handle such a big 165Ah battery.
  • your ups charging kit is malfunctioning, or not properly configured

4 - battery charges fast when its more empty.. as soon as it reaches 80+% charging becomes slow as less battery is left to fill out,. so going from 85-100% takes more time than going from 60-85%..the after going 100% it goes into float charge which requires a constant micro charge to keep battery full and stay at full..reaching that stage in even the best quality brands of UPS takes 3 hours atleast..

5 - to diagnose any problem, you need to provide us info on

  • terminal voltage at fully charged
  • terminal voltage ate complete discharge
  • battery charging DC current rate at both above states
  • wapda voltage average in most times of the day.
  • specific gravity of all the cells in your battery
  • comparison of the other ups with all of the above

This is where you need to learn to clear some problems for your self..

1 - despite the fact that djays May lack eloquent gentle toned literary skills , he is NOT BEING RUDE.. he is exactly asking the same things any would require info about solving any ones problem.

2 - this is just like you say on internet that you have pain.. and we all should help cure it.. do you expect that anyone would automatically understand what , why how of your pain without any info.? infact the only pain relief method anyone would prescribe you in that case would automatically get censored on this forum..

3 -

[quote=", post:, topic:"]

Djays:

P.S: A problem well stated is a problem half solved.
[/quote]

try to understand this statement calmly.. we all intend to help but that is only possible with proper info

4 - if you somehow donot understand how the ups system works or the complicated terminologies used here, either google them or if too busy/lazy, you can ask here directly.. someone will indeed help you understand.

hope you understand and provide proper info..

all right man. i have a aurora UPS. i just changed to batteries to 135 amp. nearly half of the previous ones.

when the ups quits charging the voltage in the batteries is 13.2 Volts

normally i get up to 190-210 volts from wapda.sometimes they drop upto 170-185

my ups charges at about 14.1 Volts. thats as far as i know.confirmation would be added soon

sorry to say, i have no idea what gravity in battery cells is...

plz excuse me for that

as per your load your 12v system with existing batteries should run fine. in future, always go for biggest capacity battery

[quote=“umaid111, post:12, topic:21244”]

all right man. i have a aurora UPS. i just changed to batteries to 135 amp. nearly half of the previous ones.

when the ups quits charging the voltage in the batteries is 13.2 Volts

normally i get up to 190-210 volts from wapda.sometimes they drop upto 170-185

my ups charges at about 14.1 Volts. thats as far as i know.confirmation would be added soon

sorry to say, i have no idea what gravity in battery cells is...

plz excuse me for that

[/quote]

google "Hydrometer"

its a 100rs device which tells the specific gravity of each battery cell. simply by sucking battery water in it.. each cell should be equal in gravity and hould be in the green zone of the hydro meter..

Hydrometer is easily available from any good battery shop.

Do adjust for temperature though

2 tables worth checking out http://support.rollsbattery.com/support/articles/4347-measuring-specific

http://batteryuniversity.com/learn/article/how_to_measure_state_of_charge