FLIPSKY new 20s 100A tiny controller (vesc based)

mxlemming said:
Phase amps is the correct way to rate a controller.

With 100 battery amps you can generate pretty much any amount of phase amps. Currently on my test bench I'm generating 270 phase amps from 17A battery at 24V.

Battery amps has no useful meaning.

Not exactly true if you are running very high phase resistance motors like typical ebike motors :)
But I agree that you should look at phase amps first and how long the controller can sustain THEM.
 
BalorNG said:
mxlemming said:
Phase amps is the correct way to rate a controller.

With 100 battery amps you can generate pretty much any amount of phase amps. Currently on my test bench I'm generating 270 phase amps from 17A battery at 24V.

Battery amps has no useful meaning.

Not exactly true if you are running very high phase resistance motors like typical ebike motors :)
But I agree that you should look at phase amps first and how long the controller can sustain THEM.
Ummm .. yes it really is true.

At very low speed you can equate power in to I^2R losses.

100A battery at 72V is 7.2kW

For a typical crappy hub motor, phase resistance is less than 100mohm; phase to phase 200mohm. That gives a current of about 190A.

But that's a hub motor that would melt with a small fraction of that power. Scale to a qs205 with 0.065 ohm phase to phase and you're at 330A... Scale that to the motor on my desk with 10mohm phase to phase and you got 850A and a fireball.
 
OP states the unit can handle 7000W?

My point is not that Flipsky "should not" give us at least a ballpark phase amps spec.

But so far they haven't,and that is the reality we need to deal with.

I am sure over time some range will be revealed by the tech-savvy early adopters

along with all the other IRL data points we'd like to see

and then those holding off purchasing due to insufficient information will feel more comfortable
 
john61ct said:
OP states the unit can handle 7000W?

My point is not that Flipsky "should not" give us at least a ballpark phase amps spec.

But so far they haven't,and that is the reality we need to deal with.

I am sure over time some range will be revealed by the tech-savvy early adopters

along with all the other IRL data points we'd like to see

and then those holding off purchasing due to insufficient information will feel more comfortable


...
They did, this is 120A and this is basically package limit an firware limit. Maybe you can hack it, but the legs will basically act as fuses :) Not the worst that can happen, btw.
 
But since we know the fets are 120amps package limited, max phase amps should be 120A or did I miss something?

Can we Say that Current flowing in phase A motor wise, is equal to current flowing between the legs of the mosfets ON related to phase A?
 
BalorNG said:
They did, this is 120A and this is basically package limit an firware limit.
Ah so I missed that.

100A battery maximum

120A phase maximum

Is that correct? At this point definitive as the vendor rating?

 
john61ct said:
BalorNG said:
They did, this is 120A and this is basically package limit an firware limit.
Ah so I missed that.

100A battery maximum

120A phase maximum

Is that correct? At this point definitive as the vendor rating?

YES, this IS vendor rating:
https://flipsky.net/collections/electronic-products/products/flipsky-75100-foc-75v-100a-single-esc-base-on-vesc-for-electric-skateboard-scooter-ebike-speed-controller
 
Is there an agreement that an antispark switch needs to be used with one of these controllers as well?
Is that switch pre-charging the controller as well as limiting sparks at the connection?

I have a dc solar circuit breaker I was using as a main switch that was keeping sparks away from my connection at the battery. They seem a little expensive for simply spark reduction considering they have no other protections (no circuit breaking for high amps, no built in temperature protection, no reverse polarity protection)
 
Chito said:
https://youtu.be/qxhpl2UHU5k

What happened at 3m30? Looks like the BMS cut out?

This seems like a lot of power for such a small box.
 
mxlemming said:
Chito said:
https://youtu.be/qxhpl2UHU5k

What happened at 3m30? Looks like the BMS cut out?

This seems like a lot of power for such a small box.

It is the bms that had it set to cut at 80a. then when i got home i turned it up to 95a
 
And if its the motor temp is correct, running at 80+ too much will kill the magnets.
 
I like the way fets cool from 70degrees to 50 within few seconds. May I Ask you where you live?

What's the limit regarding temp ?

It looks like 120A Can be held for almost a minute, I'm pretty amazed about this little box. Definitely killing kt controllers or any "cheap" ebike controller.
 
I wonder how much safety margin is available at 98% duty cycle. What is the switching frequency set to? The time to switch on / off can vary quite a bit under real world conditions cycle to cycle and change at different operating temperatures and vary between parts. It's pretty easy to get runt pulses or get some shoot through due to not enough dead time. The amount required also varies with the switching frequency since the time needed is fixed. Lower switching frequencies can allow for more power delivery, but they also stress the caps more.

I dislike the misleading spec of stating it will do 100A continuous even though it only has 12 guage leads. I managed to desolder some 8 gauge XT150 connectors at 100A sustained for only 20 mins, the wire was toasty. Also, XT150 connectors being rated for 150 Amps...LOL... NO!
 
I am new to Vesc as well and I am having a tough time getting mine to run correctly. It does well under no load but as soon as I encounter a hill it comes to a dead stop as if no current. Flipsky has not been much help so far they say it looks like a current roll off but have not suggested a fix. I have battery amps set to 50 and motor amps to 65. The motor is an HM CX72v4500w dual phase wires. I am running it at 16s on a 50a bms. I understand that some motors present problems for the vesc. But I am wondering if there is something I am missing that may resolve this issue. I used Vest tool 3.0 for mac to program the flipsky. Vesc tool 3.1 would not launch the ADC wizard for connecting the throttle. I understand the firmware is not supposed to be updated is there anything I can do or is this a motor compatibility issue . Thanks in advance
 
Hello. I have bought this same controller for my son's 1600w electric motorcycle. In previous projects he had used brushed motor controllers, in which with a simple switch it was turned off and on without problems.

Now I see that you are talking about non-sparking switches, and I do not understand why you have to use them. From what I read I deduce that these vesc-based controllers cannot be turned off if it is not by cutting the power from the battery, and that is where sparks are produced. Is that correct?

If someone can clarify that I would appreciate it.

Thanks
 
There are capacitors inside the controller and when you plug it to the battery the caps charge quickly Hence a high current in the connector for few millisecondes which results in sparks.

For "tiny" controllers such as this one an antispark Switch (which basically precharges the circuit via a resistor) is optionnal as it won't Fry the circuit, but for bigger controllers it's mandatory since they have bigger caps.

I have a Kelly controller, 72v 130amps, and I was quite worried about not using a Switch because it was required on the wiring diagram so I wrote to the technical service they replied it's okay without it'll just wear the connector over time.

I've Never Heard about vesc beeing killed when plugging the battery...
Correct me if I'm wrong.
 
It's quite possible to get substantial overshoot on the Vbus rail of the board when you first plug in due to the inductive nature of the cables.

The extent to which this is a problem depends on a number of things
1) length and loop area of the cables
2) Resistance of cables
3) nature of the input capacitors (big problem if only ceramics, the series resistance of electrolytic caps danois the effect)

Whether it damages the system is another question. Normally the MOS will survive since they're all off at turn on time and so the Vbus withstand is 2x the MOS rating.

The DCDC converters can be much more sensitive.

I've killed some lm5017 100Vdcdc converters by hot swapping 65V on a board with only ceramics. Scoping the input voltage at plug in showed a substantial overshoot.

With 1500uF of electrolytic caps the effect was much diminished, but the connector starts to take a beating.

This is quite application specific. Your mileage may vary.

Another tip... If you're going to hot swap connectors, make the ground connect first, battery+ after. When braking the connection do the opposite. This avoids dumping the inrush through whatever else is connected and partially grounded or not.
 
Thanks for the help. These types of drivers are new to me.

Although there is one thing that I still do not understand. Once you connect them to the battery, the only way to turn them off is to disconnect them?

If it is not going to be used for a week for example, what should I do? I can put a switch on the adc signal wire to avoid accidental acceleration, but will the controller still draw some current?
 
My VESC controllers draw about 1.2W at idle, so do the math for how long that'll last with your battery.

My guess is leaving it plugged in for a week isn't desirable.
 
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