Got the MKSESC75200 (for just 123$ on ali) and upgrade to FSESC 75200 alu FW6.0 went well. I wonder if there are also older FW versions for this model available? Vesc tool6.0 crashes after downloading the archive so I don‘t see what is in there. Or should I use 75300 R2 with filters manually switched off, for older releases?
I would also like to lathe down the cooling rips to get a flat surface but I couln‘t get the pcb out of the case. It is glued with silicone and sticks quite well. Any hints on how to get it out without damaging the pcb?
For GitHub you click on the file you want (I’d recommend VESC_default.bin) then click “Download”
Firmware 6.00 is 512 KB
Firmware 5.03 and earlier is 384 KB.
Probably best to download the 6.00 tool so it won’t complain about the file size. Then it’s just a matter of following the instructions on the first post. Load the bootloader. Load the firmware through the custom tab. Let it reboot and it should be showing 75_100_V2 on the firmware tab.
Sounds like there might be some bad hardware here.
Some basic tests you can do:
- Check resistance between all phases. Should be the same, somewhere around 60-120kΩ. I forget the exact value on those. If one is way off there is probably a shorted mosfet.
- Check the resistance between 3.3v and ground, as well as 5v and ground with it powered off. If it’s really low resistance, like 1-5 ohms, then the STM32 is probably short (3.3v) or something is short in the buck converters (5v).
- If you can connect, click on the heartbeat in the tool and try running “foc_openloop 50 1000”. That runs the motor in open loop at 50A and 1,000 eRPMs and it doesn’t need a proper motor detection. It’s a good test for the power stage. If that works then you can work on tweaking the motor detection parameters or the observer to see if that makes a difference (stuff needed to run closed loop). If you suspect the hardware is bad, then it’s a good idea to do this with a CC power supply or a charger with at least 5-10A rather than a battery. That will limit the current so if something does go wrong you aren’t pulling like a thousand amps from the battery and blow open a bunch of mosfets/the PCB traces.
What current level do you have the lab power supply set to? It only needs about 40mA to power up, but needs 5-10A to spin up a motor.
I’d guess there is something wrong with the hardware if you have experience with other VESCs and getting them to run well. For the bluetooth module, make sure tx on the module goes to rx on the controller, but if USB doesn’t connect it seems like there is another issue.
Since there are no red flashing lights, only a blue light with no USB, they might have forgot to load firmware in the first place. Generally blue light = 5v power, green light = turned on by firmware, red light = fault, controlled by firmware. If you have an ST-LINK v2 you can try to load it manually (maybe also use it to see if there is anything on there). There are instructions at the bottom of the first post.
The reality is that these are super cheap, and quite powerful with great thermals when they work right, but it is Flipsky after all… and the quality control / testing seems lacking.
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There is an archive section on the first post that has a bunch of old firmware files. You could use the 75100 V2 no limit firmware for the 75200 ALU. From a firmware standpoint it’s basically the same thing. 6.00 has a lot of improvements though so I’d run that unless it’s causing problems compared to 5.03.
The archive crashing was fixed in the beta release, so if you download the beta tool from the vesc project website (same place as the regular tool) it will work… but there are no older versions on the archive for these controllers. 6.00 was the first release I uploaded files for.
There might be some info here on how he was able to separate the PCB from the heatsink. Just be aware that he gets quite a few technical things wrong about the controller.
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Thanks, I got the PCB out, takes quite a bit of force, forunately, the aluminium of the power board ist solid enough, it did not bend
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Yes, I’m getting the strong impression the firmware is not loaded or corrupted. Thanks for your advice, and also your work on the firmware 
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You think they have inferior bits in the cheaper?
My flipsky version with ur firmware has been rocking!
This is max current up a hill. Why does it only do 60 amps even though set to 200 motor and 140 battery? The motor starts to magnetically saturate at 60 anyway … does the esc know there’s no point in supplying more amps?
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Glad to hear! We recently found out that the 75200 is pretty noisy in terms of current and back EMF measurements due to a poor hardware design (op amps running off 5v instead of 3.3v). But the 75100 alu doesn’t have these issues and seems to work pretty well.
There could be some soft limits activating (voltage cut-off, thermals, erpm/duty start limit), current measurement noise, or just simply not enough load. If you can send me the full log as well as your settings (file → save motor config xml) I can take a look.
You can also try applying the brakes while going uphill to increase the load and see if you get more amps.
Maybe. I did a saturation test on a 63100 and ran it up to 230A. Efficiency slowly dropped, but I never found the point where torque just fell off a cliff. It must need a lot more amps before it hits that point.
The VESC firmware doesn’t currently have anything like this. It will happily supply as many amps as will flow through the ESC.
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It’s only 45kv and magnetically saturates at maybe only 60 amps if even that. So the esc is overkill with its amp ability.
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So sorry for the bump but i wonder if anyone bought and checked the MKS 75100/200 Alu PCB and compared them to the Flipsky’s? like component etc wise? the 75200 Alu is at ~150 which means i could probably get it into my country without getting wrecked by VAT & customs and i would enjoy the extra torque 
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Ok thank you, i just wondered cause of the price difference if they maybe used worse caps etc
The caps certainly are different, I guess the MKS one since the Flipsky uses richcap in the 75200 alu, and the MKS use ymin (same brand as in the FSESC 75100 Alu PCB) altho i don’t know which is actually better lol
There are a few differences between the MakerBase 75200 and the Flipsky one.
The 75100 of both models uses 3x INA181 current sense amps which seems to work fairly well.
The 75200 they went with a quad op amp instead of 3 current sense amps.
The MakerBase one uses the SGM8584 while the Flipsky version uses the SGM8634. It’s unclear if this was a change batch to batch, an attempt to fix something, part availability, or something MakerBase does different.
What was clear is the fact that the noise at lower RPMs is pretty bad. Specifically the back emf readings that the STM32 sees.
There is a long thread on it on the VESC discord, but in the end the wave forms on an inrunner motor looked like this with either the shipped firmware or the firmware in this thread
Compare this to something like the Stormcore 100D (DRV8353RS)
Or the SKP Solo (op amps)
and it’s pretty obvious things aren’t right
This mod was made where jruncorn unsoldered the 5v power into the op amp, bent it up, and connected it to the 3.3v rail.
Which made the wave form look like this:
Then Elwin hacked modified the firmware further to average the currents together which made it run really smooth, but it’s not well tested and there may be some drawbacks
The code difference can be seen here (not incorporated into this firmware)
And here was the motor all this was run on. It’s a fairly beefy 8 pole 4kg inrunner
I don’t know if the Flipsky 75200 performs the same, and a lot of people report both versions of this ESC running fine on ebikes and scooters, so depending on the motor or use case, it may be fine for the price… but it’s certainly not the best ESC out there.
Both versions also have this problem where the caps near the inductor for the buck are rubbing on the top case and will probably short out at some point.
(from this video)
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i have the makerbase 75100 from AliExpress, got it on black Friday i think for around $50-60. still trying to work the kinks out of it… have it installed in ninebot snsc 2.0 (max g30p) powered by 13s3p but under load it stutters and bucks. i don’t know which way to go with setting it up. oh yeh i forgot to mention it’s running your firmware for the blue board version jaykup.
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We can only hope that they’ll add phase filters and INA241’s (110-120V survivability, the 240s were 80V max) in the next iteration of the 100V whatever current models
edit: i don’t see an edit button, so well uh, ina241’s for Phase shunts rather than low side
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to add on that, the ina181’s don’t have pwm rejection like the ina24x series, my guess is that there’s also a cause of the noise
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@jaykup , any updates on that? I’ve been using this Makerbase 75200 with your firmware. and It’s really jerk an noisy at low sleeps…(the original firmware felt very similar) It can handle 200A with 16S, with no warm up, but the sound it terrible. I’m using 2 harley style hub motors… the MKBASE 75200 can handle the amps, but doesn’t work for my application. I also have some UBOX 75200 v1, they are ultra smooth with those motors, but I felt it was risk running it with more than 110A.
I mean, do you believe this hack worth the risk?, or do you know where I can find more info on it?
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You are welcome to use it, but I haven’t tested this beyond a few spin ups. There is some concern at high duty cycles that it may be an issue.
This is basically the firmware in the first post, but removes the average current from each of the sensors to get rid of the noise.
Source code is in the github link above
fsesc_75_200_alu_sample2.bin (512.0 KB)
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I will try it today. I will keep a current limit of 100A when I go over 50% duty cycle, and see how it goes. thanks! the source on github you mean the korjaa changes or your link on the top?
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Both. The hw_fsesc_75_200_alu .h and .c files in the first post along with the changes to the mc_interface.c and mcpwm_foc.c listed in the korjaa github link. He was following along in the discord thread and created that github branch, while I was just modifying the code directly and compiling to see if the changes would even work.
With some more testing this could be merged with the main project, but it’s still experimental at this point