Poor backup performance on APC Home UPS with a 100Ah Battery ?

[Anonymous user]

I have a 600VA(model no. HI600SQ) ups with a 100Ah battery. I merely get about 90 Minutes of backup when running on batteries at just half the load. I had both the battery and UPS replaced under warranty and its the same.There is a scheduled power cut for exactly 2 hours everyday, so that gives 22 hours without any interruptions for the battery to charge which I believe should suffice .

The people at APC tell me that I should get atleast 4 to 5 hours of backup running at about half the load(300VA/~180 Watts) and 2 hours at full load(600VA/~360 watts). APC has load indicators to indicate the load when running on the batteries

I m totally clueless on what to do next ? The electrical appliances connected are just a couple of tubelights and fans. Regarding the replacement under warranty, the techs who examined the UPS said it was fine and so did the battery shop guy, but I got it replaced anyway just to make sure.

How would I able to diagnose if something is wrong in the wiring configuration ? Thats the only thing left for me to diagnose, but where and how do I start ?

Any thoughts would be appreciated

Anjay.

[Erasmus_apc]

The only real wiring you need to be concerned about in terms of battery connection are the 12v +/- DC ports on the back of the unit. You may be using the APC trolley that supports the batteries and provides a little jumper to attach to the HI600SQ unit or the connector that came with the unit, or you may be using a third party connector. Either way, as long as the port's connection is secure and the +/- leads are properly connected and you are using a 12v battery, there isn't much else to consider battery-wise.

Can you provide the battery manufacturer, and all the specs? I'd like to double check this runtime estimation you have been provided.

[Anonymous user]

I m using the battery connectors that was given by APC. The connection seems to be solid since its been only 4 months since I bought the UPS. And there is no corrosion at the terminals so far.


The battery is a AMCO 100 Ah, what other specs would you like to know about the battery ? Not sure what else there is, dont see much given in the Product manual. I m not sure if you have heard of that manufacturer, since I m in India.

[Erasmus_apc]

Just to confirm, that's a 12v battery? Any other manufacturer's specs you could provide, no matter how trivial they seem would help. I vaguely recognize the AMCO name but I am not familiar with their product offerings. We'll try to run another calculation once we have any other details you can give. I can also try to google the battery if needed.

[Anonymous user]

Yes it is a 12V battery.

THis is what I could find in the manual.

"Ensure voltage regulator range is between 14.2 and 14.4 for 12 volts battert. Output beyond 14.4 leads to overcharging and frequent topping up"

I hope this is helpful ?

[Erasmus_apc]

anjaykm wrote:
Yes it is a 12V battery.

THis is what I could find in the manual.

"Ensure voltage regulator range is between 14.2 and 14.4 for 12 volts battert. Output beyond 14.4 leads to overcharging and frequent topping up"

I hope this is helpful ?

I'll look into this and see if we get the same calculation. Typically APC has runtime charts for our own units using our own batteries...I'm not sure where this 4 or 5 hour estimation came from. I'll also look into seeing if there's something else configuration-wise that might be missing.

[Erasmus_apc]

Still researching the issue...had to try and pull what we could off the web to fill in some info on the AMCO battery. Will return later once we've figured the calculation out.

[Anonymous user]

Oh ok, I thought you forgot about it..


Thanks in Advance

[Erasmus_apc]

Alright we're still going to need more information since nothing AMCO has is helping with our calculation.

We need the exact battery model, since there is no info on the web about a generic "AMCO 100ah battery", power factor of the load you are using, and environment temperature.

Any data we can get on the "per battery cell" specs on the battery and total battery performance would be helpful. I don't know how the calculation was done when you spoke to a rep earlier without all the detailed information, since we typically do not provide battery runtimes for non-APC batteries.

[Anonymous user]

I do not see anything wrong with the back up mentioned in the thread. At half the load i.e, 300VA/180W the user is getting 90 minutes back up approximately. This draws about 30A from battery assuming 90% efficiency of square wave inverter. Please remember two points now:
1. Assuming 100% battery discharge efficiency also, you won't get more than 3hrs back up at half the load.
2. In reality batteries never give 100% efficiency at such high current discharge rates. The efficiency will be around 60 to 65% and hence you will actually get 65AH only. It means you should get 2 Hrs back up at half the load. There are certain other factors which can eat away the Capacity to make it 90 minutes only.

Please let me know on this and let APC people also comment on this.

[BillP]

is it just a single 12 volt battory? my system reqires 2 battory packs at 12v each, the oem battorys faild after a year havent found replacement since so i took to some custom mod work and if you know what you are doing, 2 12v marine battorys work great bulky and dont looking good but they work awsom, 500 crank amps each 1000 total, i get about 6 and half hours run time full load. ^_^ charge system is holding up well and delivers a constant v rateing. consider this option depending on your unit is not under warenty and stuff

[Anonymous user · Accepted solution]

The website has a product catalogue of all the models available in India. This is all the info I could get

BATTERY SPECS_

Model name : AMCO A100T (dry charged series)
Voltage : 12V.
Capacity(Ah)20hr : 100
Nominal Wt. Filled : 27 Kgs.
Electrolyte Volume : 7.2 Liters
Charging Current : 10 Amps
Dimension(L*B*H) : 410*176*233 mm.

Environment temperature is 30 to 34 C.

And by power factor I believe you are referring to the watts consumed by the electrical appliances.

At full load, all the appliances connected to the UPS consume 380 Watts or 600 VA. In this case I barely get about 45 minutes of battery backup.

At half load, approximately 160-180 watts is what I normally use. Here the battery backup lasts only upto 90-100 minutes average.

As I mentioned earlier when I started the thread, I have a scheduled power cut for 2 hours everyday. There are no interruptions after this power cut, hence giving it a full 22 hours to charge everyday.

Hope to hear from you soon


Thanks,

Anjay. K.



P.S: This is their website [http://www.amco.co.in/downloads.php?id=d#]

Message was edited by: anjaykm

Message was edited by: anjaykm