Lost my regen - EDIT: Got it back!

[mistercrash]

I sent a PM to Lyen about this but I wanted to post it publicly also in case someone has the same little problem. I run the Lyen 18fet controller and I recently went from 51.8V to 74V. My regen worked very well before but after the battery upgrade the regen doesn't work. I tried the three settings on the controller for regen but they don't work. The shunt is set at 1.333. Help please because the regen saves a lot on brake pads.

Thanks

 

[Kingfish]

I had exactly the same problem when I went from 10S to 15S. If you changed your voltage then you need to examine the R12 setting because I suspect your Vbatt is now higher than the Regen HVC setting.

Try reading this thread for more info: R12 mod for high voltage regen

Best of Luck, KF 8)

 

[mistercrash]

R12 settings? Vbatt higher? Are you talking about the settings of my controller or the CA? I read the first 2 pages of that thread and it got me more confused. I thank you for trying to help. I'll go read again to see if I can make sense of it.

 

[mistercrash]

So reading more of that thread I learned that there's just no regen with this controller above 75V. So what's the solution to this may I ask? Ok I'll go back to reading

 

[itchynackers]

You need to reprogram your controller (assuming your controller can handle the change). Lyen will know whether you need to do the r12 mod.

 

[mistercrash]

I'm done reading, but did I understand what I read? Maybe not. The only thing that stuck in my head from this thread is the regen doesn't work above 75V and that there's a lot of suggestions on what to do, ideas on what to do, ideas for modifications, but I didn't find a definite answer I can understand to fix the problem. :|

EDIT: itchynackers, I saw your reply after I posted this so thanks, I hope Lyen checks his emails soon and gets back to me.

 

[itchynackers]

Yes, I regen my 18 fet at 102.5V. I haven't tested it for higher, but I suppose it could. Just have lyen tell you how high of a regen voltage you can go before doing a resistor mod.

 

[mistercrash]

Lyen is sending me a resistor for high voltage regen with instructions on where to solder it on the board of my controller. What a great guy.

 

[Zenid]

Lyen is sending me a resistor for high voltage regen with instructions on where to solder it on the board of my controller. What a great guy.

I use a 6.2KΩ resistor in parallel with the 1.2KΩ R12 resistor to effectively change R12 to 1.0KΩ. This adjusts the regen voltage (and lvc) by about 20% above the program settings, making the regen voltage "75V" setting equivalent to about 90V, ideal for a 72V-ish system. I have the same mod on my Lyen 18-FET controller, too.
I detailed this mod in my write-up of Lyen's 12-FET controller here:
http://zenid10.wordpress.com/2011/04/04/ohmless-and-angry/

 

[mistercrash]

Great write up Zenid. Thank you very much.

 

[Zenid]

Great write up Zenid. Thank you very much.

You're welcome! Glad it came in handy...

 

[mistercrash]

I got this from Lyen

And he told me to solder it here on my controller's board

And after reprogramming the controller, I got my regen back.

Thanks for everyone that helped. Learning lotsa cool stuff in here.

 

[Zenid]

Nice work! Looks like a 6.2KΩ resistor. Thanks for the picture of it mounted on the 18-FET board.

Is it an EB218 board, or one of the new 318 boards, incidentally?

 

[mistercrash]

It's a 318 board.