Branch's SSG Build

[Branch Gordon]

These are the magnets I am using: Ceramic Magnets 1-7/8" X 7/8" x 3/8" Block - Set of 2 - Amazon.com

They are C8 ceramic magnets, 3850 gauss approximate pull force: 4.5 lbs magnetized through the thickness. My little screwdriver will stay attracted to the bottom of the rods to about 1/2" spacing, then it falls off...but again...my RPM's suck at that spacing and I can't find my sweet spot anymore.

Lemme do some testing with your suggestions...let me know if you think there's anything else going on. I'll post a close up of the board later his evening.

Thanks!

[Tom C]

These are the magnets I am using: Ceramic Magnets 1-7/8" X 7/8" x 3/8" Block - Set of 2 - Amazon.com

They are C8 ceramic magnets, 3850 gauss approximate pull force: 4.5 lbs magnetized through the thickness. My little screwdriver will stay attracted to the bottom of the rods to about 1/2" spacing, then it falls off...but again...my RPM's suck at that spacing and I can't find my sweet spot anymore.

Lemme do some testing with your suggestions...let me know if you think there's anything else going on. I'll post a close up of the board later his evening.

Thanks!

poor trigger function is a result of magnet strength and coil gap. so double stacking your magnets will help. Tom C

[Branch Gordon]

Did I buy the wrong magnets? I thought these were the correct type and size, as per everyone's recommendation...

What gauss are the magnets on the bike wheel kit you guys have sold?

poor trigger function is a result of magnet strength and coil gap. so double stacking your magnets will help. Tom C

[Tom C]

you have the same style we sell. 4.5 lbs pull. you just do what works best. so if a smaller gap works then use it. it is all about experimenting, I do not have 2 wheels that run the same even on the same batteries. I think you need to run just straight 470 ohm resistors, no other base resistance. you are getting good charging already. its just a matter of seeing how you can improve things with tweaks to the system. in attraction mode there is no "sweet spot" usually. you are pushing your batts to 15.3 which is good. discharge the minute the charging is done, and do it at C20 you will be fine.

on the BM3 group we asked for 20 maybe 30 runs at a fixed resistance to allow the machine to settle in and for a nice data set.

Tom C

[Branch Gordon]

Thanks Tom. How does discharging immediately affect things, as opposed to letting the battery rest?

I have attached a close-up of my board per your request. Are the teslagenx boards and coils setup to run in attraction mode by default? As in, if I connected the coil as you have it documented on the board, is that running in attraction, or do I need to go ahead and reverse the wires?

I'll keep on with my runs for a few more weeks and see if I can improve charging...

you have the same style we sell. 4.5 lbs pull. you just do what works best. so if a smaller gap works then use it. it is all about experimenting, I do not have 2 wheels that run the same even on the same batteries. I think you need to run just straight 470 ohm resistors, no other base resistance. you are getting good charging already. its just a matter of seeing how you can improve things with tweaks to the system. in attraction mode there is no "sweet spot" usually. you are pushing your batts to 15.3 which is good. discharge the minute the charging is done, and do it at C20 you will be fine.

on the BM3 group we asked for 20 maybe 30 runs at a fixed resistance to allow the machine to settle in and for a nice data set.

Tom C

[Tom C]

they are set up to run in attraction mode per the instructions. take out those final resistors and run straight 470 ohm resistors. Tom C

[Tom C]

discharging immediately helps keep the gains in the battery from the radiant. peter lindemans battery secrets lecture goes into this. Tom C

[Branch Gordon]

Gotcha. I'll start doing that consistently then. Thanks Tom.

discharging immediately helps keep the gains in the battery from the radiant. peter lindemans battery secrets lecture goes into this. Tom C

[Branch Gordon]

So..I've restarted my runs just running the straight 470 ohm resistors. Give me a few days and I'll post if there is any improvement.

Question...back when I was looking at my scope shots, I noticed that I had an h-wave from just running straight 470 ohms, up to an additional 50 ohms resistance on the potentiometer...then I would start getting multiple pulses and I would lose it. So i have quite a big gap of "sweet spot" there.

Curious...does the coil gap affect the range of resistance that the h-wave appears? If the coil is further away, does this range get smaller, and is that desirable?

[Branch Gordon]

2nd question...I just noticed that my output current is different when my primary battery is fully charged vs. when it's closer to 12V. Fully charged my charge input amps are 210 mA. At the end of the charging cycle, I'm at 190 mA. Obviously this affects COP calculations. Should I just go with the higher number for charting purposes?

[Tom C]

yes higher number.

Tom C

[Branch Gordon]

Tom-

Just an update on my runs with just the straight 470 ohm resistors.



Again, just taking 2 AH out and putting 2 AH back in. Up to .96 COP...so almost there. I'll be continuing on with the runs and watching changes...hopefully I can creep up to 1 COP here soon.

Here is a link to my spreadsheet to view as the photo is kinda small: https://docs.google.com/spreadsheet/...0E&usp=sharing

Branch

p.s. Oh, that first run has a low spot because my CBA III came unhooked for awhile on accident. Oops!

yes higher number.

Tom C

[Branch Gordon]

Getting ready to start run #9 tonight. Really seeing some nice changes in my charge curve. Here is a chart showing how the curve is changing.



I'm expecting to hit a COP of 1+ here in the next 5 runs.

[Branch Gordon]

Starting run 16 now. Still haven't gone above 1 COP. Hanging around .97.

Question....do the charge input amps change as the battery is conditioned? I haven't rechecked with an amp meter since the first run, but I'm curious since the battery impedance seems to have changed if the charge input amps are lower now?

Branch

[Tom C]

charge battery input is related to rpm... which is related to how long the base is open. conditioning will not reduce draw, but as the battery charges quicker you will see shorter charge times so you cop will go up. your current will drop a bit as the primary battery runs down.

Tom C