Charging Inverter Batteries

[Crane]

Can anyone tell me if I am having problems with my batteries. I have noticed the last couple of days when the electricy went off for a half hour, it took my batteries over three hours to fully charge back up. I have a 2400 Watt inverter and i have 8 batteries. I always keep an eye on the operation of the inverter, but this just does not seem right. Although, lately my electricity has been real weak. It has also warmed up quite a bit. Do these things have anything to do wiith my situation. Could I have a bad batttery. Any help would be appreciated.

Crane

[rubio_higuey]

The charge rate may play a role. I had my inverter (newly built) charge rate set so low, that after 6 weeks the 3 + 3 hour blackouts completely discharged the batteries (e.g. discharge 15 A, afterward-charge 10 A, difference -5A etc.) so the charge rate had to be measured and adjusted.

Your batteries may be also a little dry, so try to add battery water. You can buy it in repuestos. You can also get some EDTA and put a tablespoon in each battery cell.

[Ringo]

Could be a few things. I suggest you go to:
Xantrex Technology Inc.
Even if you do not have a Xantrex inverter, you can gain a lot of information that will help you.

Regards, Ringo

[Rocky]

Originally Posted by Crane

Can anyone tell me if I am having problems with my batteries. I have noticed the last couple of days when the electricy went off for a half hour, it took my batteries over three hours to fully charge back up. I have a 2400 Watt inverter and i have 8 batteries. I always keep an eye on the operation of the inverter, but this just does not seem right. Although, lately my electricity has been real weak. It has also warmed up quite a bit. Do these things have anything to do wiith my situation. Could I have a bad batttery. Any help would be appreciated.

Crane

Hey Crane,
One could not diagnose the problem from afar, but it could be normal that it take 3 hours to charge.
The discharge time and recharge time are not relevant.
For instance, if I had 8 batteries operating only a light, a small fan and a TV and the power were out for 10 hours, it might take only 1 hour to recharge, as the discharge was so minimal, conversely, if you are heavily loaded, you could lower your batteries enough in 30 minutes, that it would require 3 hours charging to get them back up.
Do you have a tester?
If so, does it also have an ampmeter?
How old are your batteries?
Are they all approx. the same age?
Have you ever treated them with EDTA?
Are they all properly filled?
Do they get quite hot, either discharging or recharging?

[John Evans]

are the batteries all of the same type and age? do they need topping up a lot ? do the sides bulge out slightly?-sometimes its more economical to get new -your electricity bill will go down (unfortunately they cost a fortune)


oooops i didn't read the above post

[rbstoker]

Originally Posted by Crane

..... i have 8 batteries......
Crane

Wow is that the normal amount of batteries? I have been considering the purchase of an inverter and I am still trying to sort the whole process out before I go into a store and let them "bend me over." However, the prices I have glanced at for a single battery can be as much as $150 US. If 8 is the norm I need to increase my budget considerations.

Reg

[Rocky]

Originally Posted by rbstoker

Wow is that the normal amount of batteries? I have been considering the purchase of an inverter and I am still trying to sort the whole process out before I go into a store and let them "bend me over." However, the prices I have glanced at for a single battery can be as much as $150 US. If 8 is the norm I need to increase my budget considerations.

Reg

You can get decent batteries here for $110 US/each.
The amount of batteries you need is determined by the load and duration of power outages.
In low consumption situations, 8 batteries could last you 3 days, and in high, 3 hours.

[rbstoker]

Originally Posted by Rocky

You can get decent batteries here for $110 US/each.
The amount of batteries you need is determined by the load and duration of power outages.
In low consumption situations, 8 batteries could last you 3 days, and in high, 3 hours.

Thanks for info...How does one go about determining the amount of watts and batteries that are needed. I have read several posts in other threads and it all seems so subjective and trial & error sort of driven. A couple of weeks ago when I was in Santiago on at least three days the power was off for more than half the day. Is there a chart or rule of thumb sort of guide that can let me figure out what I will need or do I just go in and say give me the biggest you got and the money left over buy all the batteries they have in stock .

Reg

[rubio_higuey]

Look, I do 12 kW usage of electrical energy per day - 6 low consumption bulbs at night, 1 "high" low consumption bulb, 2 Big TVs on about 5 hours a day, 1 small TV on about 5 hours a day, DVD recorder, 3 cable TV boxes, computer w/LCD screen and/or laptop, printer, 3 cellphone charges, ADSL modem, large 2-door fridge, water pump (average 10 mins per day), washing machine (average 10 mins per day), drier (average 5 minutes per day), A/C on average 3 1/2 hours per day - usually 1 hour late in the afternoon on full, and 2 hours at night.

The average usage is about 0.5 kW per hour, but it varies by the time of day. The most usage I have, everything on + A/C and it's about 2 kW. I don't run A/C off the inverter, and I have 2 kW inverter with 4 batteries.

Now, as the summer nears, the AC would use up more power/kilowatthours, but again, it does not effect inverter and battery settings.

[Rocky]

Originally Posted by rbstoker

Thanks for info...How does one go about determining the amount of watts and batteries that are needed. I have read several posts in other threads and it all seems so subjective and trial & error sort of driven. A couple of weeks ago when I was in Santiago on at least three days the power was off for more than half the day. Is there a chart or rule of thumb sort of guide that can let me figure out what I will need or do I just go in and say give me the biggest you got and the money left over buy all the batteries they have in stock .

Reg

For the inverter, it should be approx. double your nominal consumption and a good 20% above your max.
So, for instance, if you measure the total amps with the maximum you might ever have on at one time and you get a reading of 15 amps, then something like a Trace/Xantrex 2.4k would be perfect for the job.
As for how many batteries, you can start with 4 and see if it does the job.
If you're running out of power, then buy more.
As long as all the batteries are within a few months of each other in newness, you'll be OK.