Thunder 1220 and power supply question

[rmasu]

Hi,
I have a thunder 1220 12s charger running off a radio shack 13.8v 25 amp power supply.
The power supply is probably about 7-8 years old but works fine.
Do I have a limit on charging amps to my 12s 10000mah battery?
I was charging at 5 amps and it seemed fine, I'd like to take it to 10 amps but didn't think power supply was up to par.
I tried to look up the manual on line and I think it's only a 250w power supply.
If its not enought what would anyone suggest for a power supply?
Thank you,

 

[ecross]

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[dogman dan]

5 amps x 50v is 250 watts. So you are bumping right at the maximum rated for your PS. I'd be tempted to turn it down to 200w by charging at 4 amps unless you have a spare PS to rotate into service immediately.

10 amps charging for a 10 ah pack should be fine, but I don't have any immediate suggestions for a PS, other than to charge at 500w, something more powerful than 500w would be good. So you can run it at less than full wattage all the time.

 

[major]

The 1220 charger is rated at 300 Watts. So you're limited to about 6 Amps charging on a 12S battery. Of course you need a power supply greater than 300 W. I have one from an RV rated at 1 kW which works great with my 1220. But I'm still limited to 300 W.

 

[docnjoj]

Roger that with the Thunder 1220. I have a very old 13volt "25" amp PS and the most I can get is 5 amps out. They lie about power supply output a lot. Very reliable at 5 amps. Super charger for 12 S.
otherDoc

 

[ecross]

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[rmasu]

thanks for the replies,
when I first power on the tunder 1220 it cycles through the wattage and it starts at 500w, this is the value I should change to 300? or even 250?
ecross, thanks for the measurements.
Thanks
Can someone suggest a brand or model of power supply to get that will maximize my charger, or is what I have good enough as the max for the thunder 1200 is 300 watts anyways.
Thanks!

 

[major]

....is what I have good enough as the max for the thunder 1200 is 300 watts anyways.

Yeah, I'd say if you are presently charging to 50V at 5A you doing just about the max for the Thunder 1220. You'll never get to the 10A you mentioned. And I don't think it'd even go to 6A.

 

[dogman dan]

I'd still be inclined to set the charger for 200w, if you were interested in maximizing your current power supplies lifespan. That is, if it's a 250w PS.

Next question is, how bad do you need 300w charging vs 200 or 250? Enough to spend 80 bucks or so? Nothing wrong with getting a Meanwell S-350 for running a 300w charger. I have a knock off version of one that never balks at putting out 300w of 13v to run two chargers.

There must be other PS options that are cheaper. But a 350w meanwell would match your 300w charger perfect.

 

[RayGo]

This is my post from a previous thread: http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=46249#p675342

I have a suggestion you might be interested in.

Check out this website: https://sites.google.com/site/tjinguyte ... ects/HP47A

You can buy 2 HP power supplies on ebay for about $30 or less including shipping. You follow the instructions specified in this blog and put the 2 PS in series per his other blog. You get 1150 watts at 24 volts on the cheap. You now have both a 12v and 24v PS. The modifications connecting the 3 wires specified took me about 1 hour for both PS. Then you need to run your connector wires. I just use alligator clips for now.

Updated info:

Search the web and you can probably find a used HP 575 watt power supplies for about $20 including shipping. You can leave the T1220 max wattage setting at 500 watts. Then you set your charging amperage. The T1220 will charge at your amperage setting or automatically charge at the highest amperage, below your selected charge setting, based on the available wattage from the power supply. You should be able to charge at 10 amps with 10AHr cells with the 500+ watt PS.

FYI - I find that it's faster to charge at high amperage (over 3 amp) in bulk rather than balance mode with the T1220. Then use the 300w PS and lower the charge amperage to 1 or 2 amps and finish with a balance charge if the cells are not in balance. Hope this helps.

 

[999zip999]

I think the 1220 has a lower voltage input range. 12-15 is just what I remember it could be a lower voltage input.

 

[ecross]

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[dogman dan]

Yeah, if the PS is actually rated for 350w continuous, you are all set as you are. Plenty to run 300 w then.

 

[wesnewell]

Current RS power supplies are rated based on 12V, adjustable to 13.8V, so he's probably got a 300W PSU. He could get a 350W or larger PSU, but it would only give him a 6A max 12s charge rate, so not enough improvement to mess with imo.