Thread: Bedini SG
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Old 06-16-2018, 05:48 PM
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Aaron Aaron is offline
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bulb and batts

Originally Posted by 2SeeMore View Post
I'm not sure what specs to mention, but here's the current voltage on them, and the manufacturers stated specs.

I have 2 with pop tops and 2 sealed for now (I can get as many as I want from a couple local parts stores, though I have to pay a core charge for the ones I decide to keep).

The pop tops
Batt. 1. voltage 10.20.
AH not listed, instead says CR 120 minutes.
CCA 570

Batt. 2. voltage 12.49 (was at 12.46 before I got in a few min's of charging with the SG).
Reserve 55 minutes
CCA 525.

Batt. 3. voltage 12.46. Reserve 80 min. CCA 460

Batt. 4 voltage 12.14. Reserve 90 min., AH 65, CCA 550.
12vdc for the bulb.

You're using starter batteries - deep cycles are preferable but starter batts can be used. Never discharge the starter batts below 12 volts.

With starters, they don't have a true amp hour rating, but can be guesstimated. If the cca is 500, divide by 10 for 50 and you have a ballpark 50 amp hour rating. So 50 divide by 20 hours = so 2.5 amps is the preferable draw to get the full capacity out of the battery (if it was a deep cycle).

You will never get that from a starter battery because you can't discharge it below 12 volts without damaging them so you will only get a part of the capacity. Again, don't discharge the starter batteries below 12 volts.

If they're flooded cell batteries, they need to be charged to 15.1 to 15.3 volts and for the third time just so there is no question about it, don't discharge the starter batteries below 12 volts.

You can look at a basic wire size vs amp chart - the 12 awg is enough for 20 amps (for chassis, power transmission, etc.? - doesn't say but it is ballpark anyway). If you limit your draw to 2.5 amps within a 20 hour rated discharge then the wire is rated for 8 times more current than you need, which is good. It is more than just about current carrying capability. On all the output, you want bigger wire than you think you need so as to not introduce any impedance that can kill the radiant output to the charging batteries.

Wire Size and Amp Ratings

By the way, your coil needs to be big enough or with enough power windings to give a big enough output kick to push the flooded cell batts to 15.1-15.3. If they're old used batts you're dealing with then you will probably see those voltages no matter what because the sulfation will force the voltage up. Then the voltage drops as you desulfate it I'd recommend both presentations here: Battery Secrets & Battery Rejuvenation by Peter Lindemann.
Aaron Murakami

Last edited by Aaron; 06-16-2018 at 05:51 PM.
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