Hi. Anyone got Fardriver controller with 14: MOSFET Lowside error? Trying to diagnose for a friend. He has two ND961800's with same error! Has anyone repaired one? Aluminium power mamagement PCB with DPAK MOSFETS. No shorts from phase 1,2,3 to + or -. No burnt components. Fun. Would one open circuit phase winding in motor cause this? No obvious shorts on motor. Maybe motor hall sensors wired wrong? Any info most appreciated. Also - has anyone replaced any of the DPAK MOSFETS on the power board? Looks like a lot of heat needed to desolder / resolder. Thanks in advance. Cheers.
Fardriver fault: 14 MOSFET Lowside error. Help!
- Thread starter DDSparx
- Start date
Open circuit to the motor always shows me Mosfet error, with every of my three Fardrivers ND72680, ND96850, ND721800
Short circuit on the phase wires will be recognized by the controller. Perhaps some of the weldings inside the motor failed.
Just measure the resistance of the motor phase wires. They have to be near zero.
Short circuit on the phase wires will be recognized by the controller. Perhaps some of the weldings inside the motor failed.
Just measure the resistance of the motor phase wires. They have to be near zero.
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Did they both fail after a time of working correctly, and if so, under what specific circumstances and conditions?
If not, then when did they fail or did they ever work? If they did work, what happened between the time they did and the time they stopped?
Those are useful bits of info for you to get from the friend, so you can fix the problem and to ensure it doesn't happen again.
If you have connection problems from controller to motor, the controller can't supply current to it correctly--a poor enough connection that isn't actually an open circuit could even arc and damage FETs so that they dont' work correctly but dont' show shorted FETs (their resistances might be different from working FETs, though).
Exactly. I'm suspecting motor connections. I don't know fully at this stage how the units failed but will be doing the detective work this week. The owner mentioned re-soldering one of the phase connections to the motor as it was a bit iffy after my first visit so he may have cured the problem already. 5 out of the 60 MOSFETS show a different reading to the others in circuit. Not shorted. I have some MOSFETS on their way from the east so if they test as genuine I will replace the duff ones and try again. Poor guy has spent about £2000 on controllers and 3 years building his bike and still hasn't used it! I call that a mission! Game on.
From this I'm assuming then if the controller is powered up off the bike with no motor connection it will throw a MOSFET error? Makes sense. It can obviously handle a short circuit as there is a max phase current sense so would shut down if over current. Open circuit will just confuse the poor thing I guess. Will be back to look at the bike this week so will get to fully test the motor and connections then. Here's hoping it can be fixed. Poor guy is balls deep into the project and has a very expensive ornament that does not work in his apartment at the moment. Thank you.
Yes, I can confirm. Controler powered and no motor connected >>> Mosfet error
To test the controller you have to connect the hall sensors or an encoder and the motor, otherwhise it will show errors.
I can also confirm that the overcurrent/short circuit protection works. I melted and shorted my AWG6 / 13.3mm² phase wires during testing my ND72680, 23kW uphill was to much for them.
To test the controller you have to connect the hall sensors or an encoder and the motor, otherwhise it will show errors.
I can also confirm that the overcurrent/short circuit protection works. I melted and shorted my AWG6 / 13.3mm² phase wires during testing my ND72680, 23kW uphill was to much for them.
