Solid State Bedini

[Jetijs]

Nice setup Steve
I rewired my coil on an air core spool. It does not start to oscillate on its own, I need to put an iron core in and magnetize it. When it runs, it consumes about 3A at 12V. I can turn the voltage down to about 3V and it still will draw about 2A, but the charging also goes down. If I put some metal in the coil as a core, the amp draw decreases and the frequency goes down, so does the charging. The coil gets warm, but not hot. So I guess that this is way better than with previous coil. Now the setup is consuming the same amount of current as before, but the coil is working on higher frequency.
Thanks,
Jetijs.

[dambit]

Hi Jetijs,

Thanks. Yeah I went with the air core on mine. Because I'm only powering one transistor it doesn't even get warm. I think the 5w resistor is a bit of overkill , but it won't burn out. When I had it hooked up to the scope each pulse was 60 uS , bloody fast!!

Cheers

[Sephiroth]

Jetijs

You mentioned earlier that the heat coming from the coil is from the core. Were your welding rods electrically insulated from each other? That sounds like heat being generated by eddy currents.

[Jetijs]

Hi Seph
It might be that the welding rods are not isolated from each other, because I just stuffed them into a plastic pipe and poured some epoxy resin to fill the remaining space. Anyway, the core was heating up very much, but now that I am using air core, I noticed that the coil does heat up also to about 50 degree celsius. Maybe there is too much current flowing through the windings, but I don't think that 0,7A is much for a gauge 21 wire. Or is it?

Anyway, I made another coil form the wire I had. This one has six strands of the same gauge 21 wire. The turn count is about 2x smaller than in the first coil (did not have enough wire). I only had three more 2n3055 transistors left so I used them all, but I did not want any unused strands of wire so I connected three strands in series for the trigger winding and used the remaining strands as power windings. This other coil consumed about 2A. It oscillates at much higher frequency. The output of both coils is connected together and goes into the charging battery positive terminal. Here is a pic:



At first I used five 1k 1W resistors in parallel as the base resistance. But this was no good because the resistors heated up to 90 degree celsius and I cut the power. I replaced them with higher number of higher resistance resistors so that they would disipate heat better, but they also did heat up very much. So I used the heavy stuff



Those are 25w resistors and together they make a base resistance of about 300 Ohms. And still they heat up to 40 degree celisus. But I guess that's better than 90 degree But it seems that there is much current flowing through the trigger winding. The coil itself also heats up to about 40 degree.

I need to play a bit more with this circuit, in my opinion this much heat is not very good, although it charges the battery very well.
Thanks,
Jetijs

[theremart]

Thanks for sharing Jetijs

I have put some speaker wire on order, I am wondering how much different it will be in comparison to standard magnet wire, 18 gauge wire was recommended in the the old document of the SSG group, gonna give that a try.

I was thinking why do we have to wind the coil so close together? Why not wind it spread out over a longer spool so that it will have more room to release the heat.... I am not sure if this would be good for storing the magnetic field which collapses.... But I may try this as well.

Also considered why do all the winds have to be on the same coil..... could one not simply use multiple spools and have a single bifilar coil being the trigger?

Just some ideas....


I put the 2 golf cart batteries I had on conventional charge at 8 amps and they shot up to 14.51 V. Which is what they are supposed to do as brand new batteries. Previously I could not get the voltage over 13.80 V It seems one does need at least 3 amps.

I let them set they have dropped down to 12.84V after 4 hours, so very nice.

[Jetijs]

Just reconfigured the new coil so that there is only one trand of wire used as the trigger wire instead of three strands in series. Now I needed to decrease the base resistance to get about the same amp draw and this seems to solve the problem. Now The whole circuit is consuming 5A at 11V. I guess that three strands in series as the trigger winding did induce higer voltage into the trigger winding and this made the resistors to disipate more heat. I guess that also a smaller gauge wire would be advisible for the trigger winding.
Any thoughts?
BTW, Mart, what capacity in amp hours does your golf cart batteries have?

[theremart]

BTW, Mart, what capacity in amp hours does your golf cart batteries have?

200 amp hours.... is what the golf cart batteries have as written.

I think I will start to load test them after having conventional charge.

Have you load tested this new method yet? Sounds like you are getting it stable at least.

[Jetijs]

No. No load tests so far. But will do them soon
Thank you.
Jetijs

[Jetijs]

Hi all. I have made some load tests, but only three of them on each battery (I have two batteries). It takes about 10-12 hours to charge up one of these 200Ah batteries to 13.8V. The resting voltage of the first battery after the first charge was 12.81V and I loaded it with 4A with my battery tester. As soon as the load was connected, the voltage went down to 12V and only then stabilized and started to drop slowly to 11.4V (cutoff voltage). The tested capacity was 40Ah. After the third charge, the battery restring voltage was already 12.94 and now with the same load the voltage did not drop to 12V at the start, but instead dropped to about 12.6V and stabilized at that voltage and went down slow after that. The tested capacity now was 41Ah. Not much gain, but at least the battery is starting to function as it should. The resting voltages on the other battery also went up after three charges. Will continue the load tests and inform you.
Thank,
Jetijs

[theremart]

RE: Load tests

Hi all. I have made some load tests, but only three of them on each battery (I have two batteries). It takes about 10-12 hours to charge up one of these 200Ah batteries to 13.8V. The resting voltage of the first battery after the first charge was 12.81V and I loaded it with 4A with my battery tester. As soon as the load was connected, the voltage went down to 12V and only then stabilized and started to drop slowly to 11.4V (cutoff voltage). The tested capacity was 40Ah. After the third charge, the battery restring voltage was already 12.94 and now with the same load the voltage did not drop to 12V at the start, but instead dropped to about 12.6V and stabilized at that voltage and went down slow after that. The tested capacity now was 41Ah. Not much gain, but at least the battery is starting to function as it should. The resting voltages on the other battery also went up after three charges. Will continue the load tests and inform you.
Thank,
Jetijs

After over 3-4 months of conditioning at least, and adding additive to the batteries, "Charge-it" I was able to charge the two golf cart batteries to the full voltage as a brand new battery. 14.45 V.

Load test from these two batteries, Golf carts batteries can go down to 10.5 Volts I am told without hurting them but I went down to 11.5 V.
I got 84 Amp hours from these batteries for this voltage range.

[Jetijs]

Great results
I guess that if you go down to 10.5V you would get at least 150Ah out of them.
BTW, how do they determinate the battery capacity on such batteries. I mean if they are rated 200Ah, how did they test it, did they discharge the battery fully? And to what voltage?

[theremart]

Capacity.

Great results
I guess that if you go down to 10.5V you would get at least 150Ah out of them.
BTW, how do they determinate the battery capacity on such batteries. I mean if they are rated 200Ah, how did they test it, did they discharge the battery fully? And to what voltage?

I do not know as the spec sheet does not tell the test method used to get the 225 amp hour rating of the battery.

I know for my 12 amp hour battery it was a full discharge.

I have found that Windmill / solar cell groups don't like to let the golf cart batteries drop below 12.V However the radient charge may let you get away with much more.

I have found that the lower the amp hour pull on the battery the more amp hours you will get out.

As you note this test was over 40 hours in duration,

[Jetijs]

Yes, I saw the test duration. 40 hours is a bit too long for me, I mean if you test the battery with this kind of battery tester, you can't do anything else with the computer that uses the battery tester. I don't have a spare computer that I can use just for battery tests. Also, many things can happen in a test that long, from computer crash to power fluctuations that makes the computer restart. I also think that you have to discharge the battery to 0V to get the rated amp hours, because I have never went lower than 10.5V and I gave never seen the rated amp hours, even using new batteries, the tested amp hours are about 70% of the rated ones at best.

[hh1341]

Load test

You are right Mart.

The Renaissance Charger takes the battery down to 8 volts when it is rejuvenating a battery.(Bedini)

It automatically cycles the battery between full charge and 8 volts until the load test does not result in an amp hour increase.(radiant conditioning)

Carl

Introducting the Renaissance RC-30A12 & RC-15A24 Commercial Battery Rejuvenators

[hh1341]

Load test

BTW.....

The solar guys don't like to take their batteries down more than 50% of their capacity.

ie.......they don't take more than 100 amp hours out of a 200 AH battery.

Carl