Can any Sabvoton user/experts answer this?

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ebike11   100 kW

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Can any Sabvoton user/experts answer this?

Post by ebike11 » May 13 2020 9:00am

Hi guys
I have a 72200 model and I know its not the proper thing to do but Im willing to take the risk, regarding increasing the voltage a BIT higher. Is it even possible to bypass/override the controller voltage limit to let me try a 24s or 25s pack? The controller throws an error if 23 or more cells are connected which is a great safety feature since the bike will not operate. I have the program and cable so just wondering if this voltage can be manipulated and/or has been done?
I might open mine up and see what the fets and caps are rated at..i have no idea
Thanks!

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MadRhino   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by MadRhino » May 13 2020 9:30am

The mosfets in your controller are Techcode TDM31026, rated 100v
So, you could run 24s but there is a risk feeding the max rated voltage. I do it for a very long time, with various controllers, for speed but also because a series of four 6s rc lipo bricks is very practical. My experience is that mosfets are not equal. Some will take more than their rated voltage, while some will not survive very long even a tad under their rated spec. So I had to replace fets, many of them over the years on controllers that were not lasting. But, once I have a full set of mosfets that are good to exceed their spec, the controller does become reliable and can last a lot of mileage.

72v controllers usually have caps that are rated 100v or better.
Make it fool-proof, and I will make a better fool.
Current bikes
Street:
Trek Session 10 mod. Variable geometry. 70mph
Dirt:
Santa Cruz V10. 50mph

john61ct   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by john61ct » May 13 2020 10:35am

Are you saying to keep the **charging** voltage well under 100V ?

Or should the controller just be disconnected from the battery + charger?

Or do you mean, if the battery is sitting above 88V, to pull it down below 87V before hooking up the controller?

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MadRhino   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by MadRhino » May 13 2020 12:49pm

I bulk charge 24s lipo a tad above 100v, with the controller unplugged. I never discharge lower than 89v. I never leave a battery plugged on a resting bike. I never charge if I am not going to ride right after. I never leave batteries charging alone, since I charge them very fast. Long time habits that proved safest.
Make it fool-proof, and I will make a better fool.
Current bikes
Street:
Trek Session 10 mod. Variable geometry. 70mph
Dirt:
Santa Cruz V10. 50mph

john61ct   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by john61ct » May 13 2020 1:22pm

OK, so you find the controller is OK with an 89V full pack, just disconnect while charging.

And there is only one version of this MQCON "Sabvoton" 72200 ?

http://www.sabvoton.net/svmc/svmc72200.html


Could you link to good FETs that are good, exceed their spec

to replace the usual Techcode TDM31026?

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DogDipstick   10 kW

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Re: Can any Sabvoton user/experts answer this?

Post by DogDipstick » May 13 2020 1:51pm

john61ct wrote:
May 13 2020 1:22pm



Could you link to good FETs that are good, exceed their spec

to replace the usual Techcode TDM31026?
What are you trying to achieve with a better Field Effect Transistor?

This determines the actual choice. Cool running? High amps? Or high volts? Resistance drain, gate to source? things like that. Make the difference.

For instance, the FET in my sig.. is a 150v FET.. but slightly higher Rd-s.... and therefor loses more watts to heat... at high currents. So they are amp restricted (proportional to working voltages) compared to the 4110 FET (that only goes up to 100v... ) and has lower Drain to Gate resistance.

3077, 4110, and 4115 by International Rectifier - Infineon Technologies- are common good choices in the sizes and packages we need. All availible in surplus bulk from reputable suppliers such as PLCCenter/Radwell: Intl... If you cannot find them in a "current " listing on Digi or Mouser.
83.1v of Ironhorse XC.. :) :bolt: by Chevy :bolt: :D Broke 10 horsies :twisted: (..about 80% healed..).. :? Waddyamean? You cant tell me how many amperes/Ft.^2 of the plate ?!?!? WTF. :x :| (gottenymoem4115thangs?Yall?) :confused: Fabricator @ BSECo. Inc.

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MadRhino   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by MadRhino » May 13 2020 4:41pm

john61ct wrote:
May 13 2020 1:22pm

Could you link to good FETs that are good, exceed their spec

to replace the usual Techcode TDM31026?
You misunderstood me. I said that mosfets are not equal, even those of the same batch. Any mosfets that you feed the max voltage of their spec, is risky because some of them might not survive very long. But some of them can survive higher voltage. It is a matter of luck, testing, patience.

If you run this controller ar 24s, you are accepting a risk. You may have to replace mosfets 3 or 4 times before you have a reliable set. There are 30 mosfets in your controller, 10 per bank.
Make it fool-proof, and I will make a better fool.
Current bikes
Street:
Trek Session 10 mod. Variable geometry. 70mph
Dirt:
Santa Cruz V10. 50mph

ebike11   100 kW

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Re: Can any Sabvoton user/experts answer this?

Post by ebike11 » May 13 2020 4:59pm

MadRhino wrote:
May 13 2020 9:30am
The mosfets in your controller are Techcode TDM31026, rated 100v
So, you could run 24s but there is a risk feeding the max rated voltage. I do it for a very long time, with various controllers, for speed but also because a series of four 6s rc lipo bricks is very practical. My experience is that mosfets are not equal. Some will take more than their rated voltage, while some will not survive very long even a tad under their rated spec. So I had to replace fets, many of them over the years on controllers that were not lasting. But, once I have a full set of mosfets that are good to exceed their spec, the controller does become reliable and can last a lot of mileage.

72v controllers usually have caps that are rated 100v or better.
Yes i am considereing doing 24s pack as well but that would put the total voltage over 100V hot off the charger. Would the 72200 handle that? I guess after a few minutes of riding the voltage would drop below 100V

john61ct   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by john61ct » May 13 2020 5:44pm

DogDipstick wrote:What are you trying to achieve with a better Field Effect Transistor?
Reliability in getting into 90V territory, obviously lower amps up there, but

as much low rpm torque as possible 400lbs up steep hills

will be limiting that based on motor temp.

If the controller can stay connected while charging then 99-101V, but only if that won't otherwise reduce reliability / longevity.


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MadRhino   100 GW

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Re: Can any Sabvoton user/experts answer this?

Post by MadRhino » May 13 2020 7:20pm

It doesn’t change a thing that controller is connected or not while charging.

I disconnect the battery all of the time the bike is not riding. That, is for the battery. Nothing to do with the controller.
Make it fool-proof, and I will make a better fool.
Current bikes
Street:
Trek Session 10 mod. Variable geometry. 70mph
Dirt:
Santa Cruz V10. 50mph

ebike11   100 kW

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Re: Can any Sabvoton user/experts answer this?

Post by ebike11 » May 13 2020 8:28pm

john61ct wrote:
May 13 2020 5:44pm
DogDipstick wrote:What are you trying to achieve with a better Field Effect Transistor?
Reliability in getting into 90V territory, obviously lower amps up there, but

as much low rpm torque as possible 400lbs up steep hills

will be limiting that based on motor temp.

If the controller can stay connected while charging then 99-101V, but only if that won't otherwise reduce reliability / longevity.
Why do you want to keep your controller and battery connected?

ebike11   100 kW

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Re: Can any Sabvoton user/experts answer this?

Post by ebike11 » May 13 2020 8:31pm

I think the 72150 and 72200 voltage cant be bypassed even if i connected 24s...

Volts   10 W

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Re: Can any Sabvoton user/experts answer this?

Post by Volts » May 19 2020 8:36am

The 96120 controller can run 24s but both motor and controller gets hot fast, I’m at 23s at the moment and it’s cool/warm and is acceptable but my guess is 22s would be the best for 96120 controller. I haven’t tested 24s on the 72200 version my guess is it would run hot stay with 21s I’d say.

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