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mid north Matt

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Joined: 06/01/2011
Location: Australia
Posts: 58

Posted: 04:37am 21 Jan 2011

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found a pool filter box [surechlor 4000]at the dump shop with a twin 18v by 7amp winding's on it's tranny so are these good for making a battery charger out of?i was thinking of two 35a bridge recterfier's and a series parael switch for 12/24v charging running through a c40 trace charge controller,what do you guys think?

Pt Wakefield Matt

Gizmo

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Joined: 05/06/2004
Location: Australia
Posts: 5078

Posted: 05:11am 21 Jan 2011

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Hi Matt

I've built a power supply out of a pool clorinator, yeah, those transformers can pack a lot of amps. I think my transformer put out about 10VAC, after rectification that ends up at 14volts. I used a 35A bridge and big old capacitor.

18volts, is that AC? Might be too high. 18v times 1.414 to get the DC value after rectification, works out about 25VDC! To charge a 12v battery you want about 16 volts ( boost charge ), so you need 11VAC.

Is the secondary winding accessable, could you take a few turns off the transformer without destroying it?

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
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mid north Matt

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Joined: 06/01/2011
Location: Australia
Posts: 58

Posted: 12:38pm 21 Jan 2011

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hi Gizmo
i'll have ago at taking some turns off if i can or ive got another tranny similar to yours which would still thump in a decent serve of power to my batteries on days of bad cloud cover

Pt Wakefield Matt

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Joined: 02/12/2009
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Posted: 12:31am 22 Jan 2011

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Hi Matt

How about making a power supply along the lines of the one PETE Downwind listed in the projects page, for not a lot of extra effort you have a battery charger and a variable power supply. http://www.thebackshed.com/Windmill/articles/VariablePowerSu pply.asp

A few extra transistors and it would be a mean multi voltage battery charger / power supply.

All the best

Bob

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Greenbelt

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Joined: 11/01/2009
Location: United States
Posts: 566

Posted: 03:34am 22 Jan 2011

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Hi Glen,

I didn't understand your post at first. I thought you had reversed the .707-1.41 rule,
It finally dawned that you are considering the data tag on the pool filter rather than
the actual voltage on the coil when in operation.
I started this post. Had to finish with an edit. Regards---Roe Edited by Greenbelt 2011-01-23

Time has proven that I am blind to the Obvious, some of the above may be True?

mid north Matt

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Joined: 06/01/2011
Location: Australia
Posts: 58

Posted: 10:45am 22 Jan 2011

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hi Bob
ive got a varible power supply i found out the dump years ago,it's got a tafe student wound tranny with a commercial printed circuit board with lots of componets on it,0 to 30 volts via 10 turns or so pot dont know amps but lit a 100w 12v globe up very brightly so might make a good charger with a big heatsink on the power transistor and fan's in the case.

Pt Wakefield Matt

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