Vesc over_temp_fet

I have 2 4.12 VESCs both on 2.18. i changed the maximum input voltage on BLDC tool to 22V because that’s what my batteries are rated for. but both my VESCs shat themselves. I reset all settings but i cannot start the detection of the motor, because all the temp readings are between 300-400 degrees. HELP!!

First increase the maximum input voltage. Try it with 50V. Shouldn’t be a problem. Even if your batterie has less. Because if your batterie which is most likely a 6S is fully charged it will have 4,2 V * 6 = 25,2V. So it could be that the vesc shut’s down before it can detect the temperature. So give it a try.

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yeah i have 2 LiPo in 6s. the default max voltage is 57 and i get a OVER_TEMP_FET error

Leave the max input voltage at 57V.

did you change the temperature settings?

Please post a screenshot of your actual motor configuration. That would help.

I’ve left the voltage at 57V and the min temp is at 80 max 100

Get a close up picture of R1, it’s near the fets

You said in you first post that you have a 6s battery. That means at 3,7V * 6 = 22,2V,

But you set the Battery cutoff start to 33V and the cutoff end to 30V. That means the Vesc drecreases the power at 33V and stops working at 30V to prevent you to destroy your battery. And a fully charged 6S battery can only provide 4,2 * 6 = 25,2V. So you should set the correct values for a 6s batterie. For example cutoff start at 3,6V * 6 = 21,6 V and cutoff end at 3,4 * 6 = 20,4V.

So at the moment your Vesc thinks that the battery is completely discharged.

And what motor do you have. Because 40A max motor current seems a bit low.

its for a school project, and its at school right now. ill try to get a photo when i can

I’ve tried reducing the voltage limits, but that’s what made the VESC fail in the first place. they used to work on the default setting that I’ve shown there, but i know id have to change the min and the max voltage, but now after changing the settings the VESCs don’t output power to the motors

As for the motors they are 85A. So if i change the amps it might work. but as I said, the VESCs aren’t even outputting power in the first place, so I don’t know if it would make a difference

you should not play with the max voltage limits always leave it to 57V, it will only create problem.

i learnt that the hard way. is there any way to fix it if you do change it? I don’t know if I’ve fried the VESC

Take picture of R1 (that the Temps sensor) like @Blasto said, to see if the problem is coming from a broken sensors, are the blue light still lighting…

You will never get it to work with 6S and those battery cutoff values of 33V/30V.

What cutoff do you recommend?

The light is still lit yeah

Change your settings to this for 6S

Since I don know the chemistry of you battery I can’t answer this, but that table might give you an indication. It’s generally for LiPo cells.

But with 18650 for example you can go closer to the limits (means cutoff start at 3.2V and cutoff end at 3.0V since they are capable of going much lower). Still, it’s better to stay on the safe side.

:confused: got this same problem… Was running fine on a 170kv 3kw then I hooked up the enertion 6355 - reflashed firmware and mosfet temps all reading 300 - 400 degrees