Sabvoton 7260 strange throttle Control, pleas help

matschi140

10 mW
Joined
May 26, 2019
Messages
31
Hello,

I am new here, and need some help please.

Can anybody help me with Sabvoton SVMC 7260??

Its mounted in an electric scooter with 1500watt 60V HubMotor.
And 60V60AH Lithium NCM Battery.

I have connected 3 speed plug, on low speed everything is ok, but on high speed when going over 50kmh and releasing throttle it brakes really hard until stop, even with regen deactivated.
Can it be that the motor has some kind of overspeed protection?

Hall test all went good, i just dont know the exact magnet count, i let it
On stock 23

Also the Throttle control is very twichy, from half twist to full twist it does not change really much and holding same speed is really hard, either it accelerates or it brakes

Any help appreciated

Thanks
 
Here the setup:
I tried both rated dc current 30A and 60A but same problem... With 30A just accelerates not that fast.
 

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Find 12v or 5v brake settings. High or low voltage brake and turn it off if you have it. Mine did also brake in the begining and stopped after I turned of that setting.

It is weird that it is only on that setting it is deaccelerating as you specify. Also when going fast of course you'll lose alot of speed when turning back the throttle.

You can change throttle settings by changing "throttle mid voltage (V)" to 2-4v and it will change how fast it will change speed when you turn your thottle. Also you can change throttle "mid current (A)" to higher or lower value. Change one setting first and se what happends and then change the other setting after that.
 
Yes this is exactly what i was thinking too, so i tried with regen off and with ebrake off in the settings but still the same issue. Or do you mean to disconnect the brake wires from Controller completely?

The strange thing is, that it does it only when driving above about 55kmh, when i drive at low speed example 40-45kmh all is good.

I was thinking that maybe the motor has sone kind of overspeed protection maybe?

The motor is rated for 60V 1500Watt only, but with sabvoton it pushes 4000watt peak when accelerating hard, and no problems with that. Only when speed is over 55kmh and throttle is released it brakes like ebrake with 100A current, it nearly blocks the wheel...

The only thing i dont know is the magnet count, can it cause this problem when magnets are set wrong?

Now its set to 23 poles i don know if its right? But as i know this is only needed for speed reading..
 
matschi140 said:
I have connected 3 speed plug, on low speed everything is ok, but on high speed when going over 50kmh and releasing throttle it brakes really hard until stop, even with regen deactivated.
Can it be that the motor has some kind of overspeed protection?

Thanks for the screenshots,

It's a bit weird. I never had this problem but I never used the 3 speeds so that migh be related.
I would try to play with the "Internal speed limit", "Mid speed limit" and "Low speed limit" setups. Also check what options you have in the "speed limit mode".
I don't think this is related to your motor poles and stuff, if you did the calibration properly, which it seems like you did since it apparently works fine on the other gears, this should be fine.
Never hurts to do it a few times though. Can you describe how you proceeded for the motor calibration (just a sanity check to make sure that you did it properly)

Also, if you don't use ebrake or regen, put 0 in their current values. I don't think it makes any difference but who knows how well the app and firmware are coded...

An other thing: you have set a reverse speed limit. Does it imply you have some kind of reverse switch? In which case, are you sure its wire is plugged as it should?

matschi140 said:
Also the Throttle control is very twichy, from half twist to full twist it does not change really much and holding same speed is really hard, either it accelerates or it brakes

I don't know what throttle you are using, but you might want to adjust its settings.
Min voltage should be OK.
Max voltage might be more around 4.8-5V, you should be able to see it from the app when you twist the throttle to the maximum position in the home screen page.
For Accelerate (ms) and decelerate (ms) I usually go with 50ms, it makes the throttle more predictible and reactive.
Throttle mid voltage is ok, you can play a little with it to adjust the throttle curb later
Throttle mid current is too high, basically you ask your controller to deliver all the power when your throttle reaches 3V, hence that "ON/OFF" feeling. Try to set it to half the value of your rated max phase current, should make things better. Then adjust higher if you find it too weak.
 
Thanks for your Help!,

About the Hall Test, i set the amps to 15A then start the Test, the Wheel turns slowly and in the App it shows status "in progress" after that it stops and says "Hall Test OK" then i save the settings, thats it, i think this should be fine.

About the reverse limit, i never touched that setting as i dont need it. i also have no wire connected and no switch for it. I will try to set it to 0, then Test again when weather gets little better here.

Throttle is Standard hall Throttle, i already set the upper voltage to 5V, i will try reduce the throttle mid current, hope it will be more linear and controllable then.

This is already the 2nd Controller, the first one blew up the fets on the 1st test ride but it did the same strange hard braking like this new one now..

Thanks so far
 
matschi140 said:
Thanks for your Help!,

About the Hall Test, i set the amps to 15A then start the Test, the Wheel turns slowly and in the App it shows status "in progress" after that it stops and says "Hall Test OK" then i save the settings, thats it, i think this should be fine.

Seems fine, that's the correct process.
I usually put a bit more amps than this, but my wheel is probably much heavier than yours so I don't think it's a concern here.

matschi140 said:
About the reverse limit, i never touched that setting as i dont need it. i also have no wire connected and no switch for it. I will try to set it to 0, then Test again when weather gets little better here.

Yeah, you can try that.
You can also try to completely disable the gear switch, by default it will go to max speed if disabled. In which case you should be able to know if this issue involves any kind of wrong setting in the gear switch itself.

Lastly, maybe you can try to set up a very slight regen, like one or two amps, and see if you still have the problem.

matschi140 said:
Throttle is Standard hall Throttle, i already set the upper voltage to 5V, i will try reduce the throttle mid current, hope it will be more linear and controllable then.

Yeah, it will for sure.

matschi140 said:
This is already the 2nd Controller, the first one blew up the fets on the 1st test ride but it did the same strange hard braking like this new one now..

Mhhh, that's some new info, quite puzzling.
If both controllers had the same issue it is possible that the controller is not the problem. Might be the motor, sounds a bit like a short between phases. But I can't think of any reason why this would occur only in such specific conditions.
That would also explain why your first controller blew up, shorting phases is really bad for the FETs, most controllers can't take it. I'm not sure the Sabvoton is protected agains phase short, and even though it were, it wouldn't quite like it for too long.
 
If both controllers had the same issue it is possible that the controller is not the problem. Might be the motor, sounds a bit like a short between phases. But I can't think of any reason why this would occur only in such specific conditions.
That would also explain why your first controller blew up, shorting phases is really bad for the FETs, most controllers can't take it. I'm not sure the Sabvoton is protected agains phase short, and even though it were, it wouldn't quite like it for too long.

If its really a short, should it then not be present all the time?

I tried to repair the first one, i replaced the fets and measured all against positive and negative, noshorts in the controller, the i connected it to the scooter and turned it on. i twisted the throttle and it blew up again before the wheel moved, also triggered the dc circuit breaker. i took it out, measured it and there is again a short between green phase and negative.

Then i placed the 2nd controller in and it works again, so ithink maybe the motor is not the problem..
 
matschi140 said:
If both controllers had the same issue it is possible that the controller is not the problem. Might be the motor, sounds a bit like a short between phases. But I can't think of any reason why this would occur only in such specific conditions.
That would also explain why your first controller blew up, shorting phases is really bad for the FETs, most controllers can't take it. I'm not sure the Sabvoton is protected agains phase short, and even though it were, it wouldn't quite like it for too long.

If its really a short, should it then not be present all the time?

Yeah, that's what puzzles me, a short usually occurs all the time.
Except maybe if there were a tiny scratch somewhere in the insulation, and under particular circumstances like a specific vibration, the wires would come into contact.
That doesn't make much sense to me but I can't really come with a satisfying explanation. Two controllers having exactly the same issue for no apparent reason doesn't seem much more logical to me.

Do you have an other motor you could test the controller on?
Can you give more details about what your exact setup is?
 
Do you have an other motor you could test the controller on?
Can you give more details about what your exact setup is?

i have a 5kw Ebike running a SVMC7280 with Cycle analyst and 72V60AH Battery, its pushing 6.6KW Peak with that setup and works perfect on throttle mode as well as on PAS mode with SEMPU torque sensor.

Its all wired up and i dont want to take it all apart for testing, but if there is no other solution i will have to do it.

Another strange thing is that when i have the scooter on the stand with rear wheel in the air, this issue is not present.

I can accelerate to max rpm and release the throttle, it just spins slowly out (when regen is disabled) or it brakes slowly (when regen is enabled with a low current)

so for testing another motor i would need to ride it..

the stock controller is a cheap chinese 30A squarewave controller without regen, and battery is a 60V 60AH NCM Pristmatic cells. But the stock controller also dont get the speed up over 50kmh.
 
Yesterday the weather was ok so i took it out for a ride.

I set throt mid current down to 80A, and throttle control got much better, but i had no chance to test at full speed, because it stopped totally, i think the BMS has blown.

I can measure 57V on Controller Input, but as soon as i turn on ignition it fall totally down to a few volts and i can see the headlight just flickering on and off.

It also dont take a charge, but when i turn on ignition it charges. as soon as i turn off ignition, the charge stops.

Any Ideas? otherwise i will take out the BMS and replace it for a bluetooth one i think.
 
matschi140 said:
Yesterday the weather was ok so i took it out for a ride.

I set throt mid current down to 80A, and throttle control got much better,

Good, at least this part is solved.


matschi140 said:
but i had no chance to test at full speed, because it stopped totally, i think the BMS has blown.
I can measure 57V on Controller Input, but as soon as i turn on ignition it fall totally down to a few volts and i can see the headlight just flickering on and off.

Yeah, that sounds like a BMS cutoff.

Most BMS will recover after being plugged into the charger. Apparently yours doesn't, for some reason.
Do not make the mistake of assuming that your BMS is defective. It could be, of course, but it is much more likely that the BMS simply does its job and cuts off the power for a good reason.

First thing you'll need to do is to open your battery pack.
Then, try to unplug and then plug back the balancing wires. If there are several balancing plugs, try disconnecting the highest voltage ones first, then the lowest. And then when plugging back, plug the lowest voltages cells first, then the highest.That did the trick for me last time. It should reset the BMS, so that will clear any firmware error if that were to be the issue.

If it still doesn't work, then it could mean that one cell group has reached either the lowest voltage limit or the highest.
You need to measure the voltage of each cell group and report it here, like this:

1: 3.98
2: 3.97
3: 4.02
etc.

Then once we know that we can see how to fix it.

Wish you good luck, that kind of problems is always a pain.
 
Hello guys, some time went, but i managed now to get new BMS and wired all up already, i have now bms with bluetooth and active balancing function and i can see all battery data in real time while riding.

The Problem is still present, what i did now, i disabled the E-brake function totally and enabled regen and set it to 15A this is working now, and when releasing throttle it shows on bms +15A so this works, i can also see the Amp draw on acceleration and all cell voltages.
The problem appears only when d
Riding above 40-45kmh, if i release throttle while beeing faster than 40-45kmh it naerly is blocking the motor and i see +65A!! as regen current.

I have activated the 3 speed function and it is working, if i am in low speed mode the naximum speed is about 35kmh and o. This settings all is working as it should.

What can cause this strange behaviour?

Thanks for your help
 
I'm not sure if this could be of any help, anyway... I'm using MQCON 7245 without PAS connected, only throttle. On lcd I can choose (supposedly PAS setting) 0 to 3, but without PAS connected it sets max speed limit and max power, for 1 being the weakest and 3 being the strongest. With the wheel off the ground and PAS set to "1" I can do max 28km/h, with "2" about 60km/h and with "3" just over 90km/h. I realised that If I start going down the hill, but I leave PAS set to "1", even though I don't have regenerative braking or e-brake turned on, the controller tries to slow down the bike to max speed allowed in PAS setting "1" by applying e-brake itself. As soon as I change PAS to "2" it will continue to accelerate down the hill. Similarly, when I reach about 60km/h while going down the hill, the controller will apply braking force unless I switch to PAS "3".
 
That's very weird, can't think of anything that would cause this.
Maybe two things to try:
-If you have a QS motor with a second set of hall sensors, then try using the other hall sensor plug.
-Try to disconnect everything from your machine except for the absolutely necessary ones (throttle, phase, battery positive and negative, hall sensors and ignition), see if that solves the problem, then add the other wires one by one until you find the culprit.
 
I just had an other look at the sceenshots posted earlier, and I found something that seems weird to me:
Current limiting voltages and Over voltages seem very, very low.
Current limiting voltage is set up at 52
Over voltage is set up at 77, which sounds insanely low to me
That could explain the issue, during regen the controller might see high voltages coming from the motor and maybe it shuts down briefly because of that, or, more plausibly, raises the current dramatically to lower the voltage, causing the weel to lock.

From what I see on some screenshots I found on Google, other 72V controllers seem to have different values: 62V for DC current limiting voltage, and 95V for Over voltage, which seem to make more sense (see here on this crappy screenshot of a 72150 Sabvoton): https://sc01.alicdn.com/kf/HTB1.jCCoASWBuNjSszdq6zeSpXam/231914185/HTB1.jCCoASWBuNjSszdq6zeSpXam.jpg_.webp

Maybe you should try that, there's a chance that might work.
 
Does this have same properties as bigger models for example 72150 which seems to be popular?

Can you recommend this to Cyclone 3000w motor? I need good e-brake and most importantly field weakening. Does 7260 have that later one?

Shops say this SVMC7260 is recommended for some 1500W motors? Isn't it bit strange if this can push 60A continuous? Can this feed at least 50A continuous?
 
Hey Matschi, did find out??

i have the same issue as you, and i am sure it's not coming from the motors, it does the same on 3 motors i have xf40 xf19 and 3k turbo.

I still don't know what the hell is happening ....
 
Hey Seboon,

Yes i found out what was rhe problem. It was the field weakening function. I turned it of and it didnt do it anymore. Try set field weakening down to 0 and report if it helped.
 
Hi!
I also have the same problem. But I would really like to use field weakening as my scooter is pretty slow otherwise. Did any of you find a way to get rid of the "panic break problem" and still use field weakening? Or is there any other way of increasing the top speed without field weakening?
 
Yes ofc :lol:
That means doing a battery rebuild though. Any idea of how high voltage the Sabvoton 72v will manage?
For example running it with a 22s battery.
 
21s is save without flux weakening. With activated flux and on the main stand you can easily kill the controller.
But regen braking works only under 84V.
 
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