Infineon controler cannot handle 60 volts, is there a fix

[recumbent]

I bought 60 volt lipo's but found out my Infineon controler can't handle it. I still use my older set of PSI batteries that are 48 volts, but was wondering if i can knock down the 60 volt lipo pack. Or set my Cycle analyst to a lower amp setting.

I also have an older controler rated 48v from a year ago with 100 volt caps in it but not sure if the 12 mosfets can handle the 60 volts either. "Comcycle" sold the controler to me last year, I'll contact them to see if this older controler is safe to use with 60 volt batteries.

Is there an easy fix for my weaker Infineon controler to handle 60 volts?

I know i probly have to eventually purchase a higher voltage controler.

 

[amberwolf]

Which controller, specifically? There are several threads around about modding various ones for higher voltage. If you know which one we might be able to find the right thread to show you how.

 

[dnmun]

what about the 60V will it not handle? is it 60V or really 67V?

the stock caps are 63V and the FETs are 75V rated but can handle up to 88V it appears.

 

[recumbent]

The two controlers are from different suppliers, the newer one from Ebike.ca which was only $5 more than the 20 amp unit should have been a red flag right there.

The other one from Comcycle, also 35 amp and 48V but has 100 volt capacitors inside. But not getting much info from them so far.

I've already ordered a new one from Lyen who makes them for this type of application, plus 45 amps i believe.

Maybe i'll get someone to modify my Comcycle controler as a spare.

62 Volts is the max voltage i'll be using along a 7 ft long bike, 2x8s lipo packs paralleled to 12amp/hr. They are the new 5800mah bats. Which BTW were perfectly balanced.

Edit: Oops, it is definately 67 volts fresh off the charger, Thanks for that "Dnmun"

 

[dnmun]

did it blow up? or just not run the motor?

you should be right on the upper limit of input voltage without modifying the input power resistor if that was a 36V controller. 67V - (35mA x 300 ohm) = 56.5V to the regulator and it is limited to 40V above the output voltage so you are pulling the 12V rail up to 17V, which will not kill the drivers or FETs. imho.

 

[recumbent]

Dnmun, thanks for giving me some hope. I haven't used the lipo packs with these controlers yet because i've not been stranded yet after years of E-biking.

I'm not worried about the LVC because i use CellLog on these lipos with buzzers to warn me. Thanks again.

I was hopeing to just charge the packs to 4volts each at the beginning till i get my proper one in the mail, and hooked up.

 

[dnmun]

so when you said you found out that the controller would not handle it, you meant you decided that the voltage from a battery you are yet to build is too high for the controller? i haven't figured out what failed yet.

but if you put together that pack, i meant the stock 36V controller would be pushed a little over the limit of input voltage.

you can add another input power resistor in series if you wanna, but once the bike is under load, the voltage from the battery will drop, and the current used by the controller will increase to about 55mA so that will pull the voltage that the regulator sees on it's input well down into a 'normal' range and it should be able to maintain the 12V rail @12V, and the risk is only when at idle on a hot pack.

risk meaning the caps may be overstressed by the voltage of 67V being a little too high for the 63V spec they are built to.

 

[mwkeefer]

Hello!

I run my stock infineon 9FETs on 15 and 18S lipo without modification - that's max voltage between 63 and 75.6v. My infineons and 9C run fine with this much voltage, yes 60v is a bit over the limit but the capacitors inside (which are your first ceiling) are rated for 63v but again I find they work okay with up to 75.6 hot.

You can always swap out the caps for 100v versions then the next limiting factor is the 75v FETs.

-Mike

 

[dnmun]

i have had 90.6V on the input to a stock 9FET infineon controller too and not blown the caps, but not under load.

 

[recumbent]

Wow, that's encouraging you guys, your definately brave.
I've never tried my 16 series lipo pack on the 48 volt controler yet, but phoned the supplyer and they warned me it's not made for it because of the 60 volt fets and caps.
I've ordered a larger controler from Lyen already, wish I spotted his controlers earlier and avoided splicing wires twice cause i hard wire my system with butt connectors.

Whats the resistor mod you speak of "Dnmun" , Can i just series connect it to my 60 volt pack?
Maybe i'll just wait for the proper controler from Lyen and use my old (and partially wore-out) 48volt PSI pack for now. Thanks for the help.

 

[dnmun]

you can add a second power resistor in series with the 300 ohm resistor that drops the voltage to the LM312T voltage regulator and that will reduce the input voltage to the regulator. but from the calculation i did for you above, it appears that the regulator will still be ok even at the 67V, and when under load the 67V will drop to 60V and the controller current will increase so you should still be ok and the 12V rail will remain in the 12-15V range which is ok for the mosfet gate drivers.

in short, you can use that controller with that battery without much risk, imo.