how long does it take to power my battery

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
30/07/2010 08:16

My fan stopped to work in the night, I wonder how long will it take to charge my large leisure battery which is connected to my charge machine but works from my generator not mains. Any ideas?

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
30/07/2010 08:17

Forgot to say I just want enough power for one fan of 50w to run throughout the night, its been working for 7 nights when the battery was new (without need for charge).

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
30/07/2010 18:37

re posting for guidance

Rocker



Joined: 24/09/2008
Posts: 384

Message Posted:
30/07/2010 18:43

To charge a battery depends on many things, the battery amp, hours, the charger distribution, what condition the battery is in. To name a few. If completly flat could take upto 10 / 12 hours if a large capacity battery.

sharond31


Joined: 27/07/2010
Posts: 5

Message Posted:
30/07/2010 22:17

Keep the battery charging even when the fan is on.

So, you will always get a backup.

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
31/07/2010 08:15

my dear friend lent me a battery charger but im advised it may not be big enough, the new week old battery is 180 amp and the charger reads 6 amp, so what size charger would I need please?

rigsby


Joined: 21/09/2007
Posts: 912

Message Posted:
31/07/2010 11:02

If charger gives out 6 amp charge it will take 10 hours to put 60 amp back into battery.So just leave it charging.

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
31/07/2010 11:39

Oh dear dear, technical things again.

So Your brand new battery is 180 AH, presumably 12 volts.

1. How long will the battery last for a 50W fan? Assuming 90% efficiency and the battery packs in when down to 10% full, it will last 180*12*0.9*0.9/50=35 hours in total.



2. How long will it take to charge? It will depend on the capacity of your charger and how empty your battery is. Suppose the batterry is charged at 6 amperes, and it is 90% empty, it will take 180*0.9/6=27 hours



3. Bear in mind that the more you empty your batterry each time, the shorter gets its life. Its best to have an electronic cut out to cut off the batterry when the voltage falls to 11 volts.



4. The lower the charging current, the better for the life of the batterry. Fast charges like 30 Amperes is very bad for it.

ismet

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
31/07/2010 18:55

Yes Elko2 my 1 fan did last about 7 nights from the new battery. Trouble is I dont know when its low (it has no light) and on the 8th night the fan just stopped )so yes that would be 27 hours). I put it on charge for about 6 hours approx now, but the fan turns for 5 seconds and stops. So yes I understand no 2....it will take 27 hours to charge. My geni is on for about 4 hrs a day so Im looking at another 7 days for it to charge! The electronic cut out....how do I attach that to the battery I wonder?

no. 4, so Id be ok if I purchased a 15 amperes rather than stick with the 6 amperes.

Thanks in anticipation. You are most enlightning.

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
31/07/2010 19:55

1. Get yourself a cheap multimeter, probably less than 50 TL and ask them to show you how to measure the voltage of a battery.

2. Check the voltage of the battery and don't allow it to go below 11 volts, simply turn it off. If you have a good friend with some basic electronics he can design one for you to cut it off automatically. This is the sort of thing I used to play with when I was young but I am too old now to bother with it. Now with semiconductors everything is much easier.

3. Stick with your 6 A charger, it is better than 15 A for your batterry unless your genny is not on long enough to charge it properly.

4. I am afraid even when your fan stops working it keeps on drawing current from the batterry and that is the worst thing, it discharges your batterry fully which is bad for its life and also takes more time to recharge it. You should turn it off when the fan stops working.

5. When charging, occasionally switch off the charger and measure the voltage, if its about 12.5 volts, it is almost full. alternatively get yourself one of those gadgets that measures the density of the acid and tell you when your batterry is full. It has red (empty), yellow (half full) and green (full) sign on it.

regards

ismet (The most helpful member )

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
31/07/2010 20:41

thanks dear!

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
02/08/2010 09:35

Elko 2



Can you translate into Turkish what I should ask for in the shop describing the multimeter. thanks

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
02/08/2010 14:29

Simply ask for a "Multimeter to measure electricity". They will know it. Or show them this picture. http://images.gittigidiyor.com/2418/MULTIMETRE-DIJITAL-OLCUM-ALETI__24184303_0.jpg



Here is a picture of battery hydrometers normally obtainable from shops who sell car batteries. http://www.supplierlist.com/photo_images/147657/Battery_Hydrometer.jpg You simply suck in some acid from the battery and it will tell you how full it is.

ismet

LostFound


Joined: 03/08/2009
Posts: 387

Message Posted:
02/08/2010 19:04

yes found them in a shop in Karakum. thanks once again.