What are FETs?
FET is a short form of mosfetFet. FETs in an esc is just an electronic switch which switches voltages between the three wires which causes the motor to turn. what often happens is that the FETs have a lot of switching due to high current draw and that causes them to over heat and fail.
Or sometimes the heatsink are not properly in contact with them, which causes them to over heat and fail!
Here's a few steps on fixing your fried ESC:
Step 1: YOU WILL NEEDED!
• An Old Motherboard
• A FRIED ESC
• A Soldering Iron
• Piece Of Heatshrink (could use tape)
• A Heat Gun (optional (If you are good at desoldering with a solderig iron then there is no need to buy one or if you have it use it )
Step 2: EXTRACTION OF THE FET's!!!
• Use a Heat Gun (the gun which blows out hot air)
• After a couple of minutes take a screwdriver and slide the FET out of place.
You could also use a soldering iron if you are skilled. (trust me don't do that. But if you can do it, do it) This way may damage the FET.
OR The other way!- this way is dangerous but faster!
• Find the FETs closest to the border of the PCB.
• Turn on your cooking stove to high flame!
• heat the under side of the FETs (Don't heat for too long (less than 25 seconds) and DON'T INHALE THE SMOKE Given out)
• Take a screwdriver and slide out the FETs. (lol I used a lighter at that time :P)
Step 3: Removing the Failed FETs From the ESC
• Take apart the ESC's heat shrink
• Remove the heatsink (the aluminium thingy)
• find the faulty FET (Usually the FET will be half broken or it may be bulging out)
• use a heat gun or desolder it (heat gun would be better)
• if using the heat gun heat the FET for 30 -40 seconds
• try to move the FET with a screwdriver while heating it.
• finally it should come out!
The next step has the video of me removing and replacing the fet with a soldering iron!. so watch that video :)
Step 4: Placing the FETs On!
Just tape it up or put some heatshrink! and you are ready to go!
Oh and don't forget to replace the heatsink!
(After soldering please check for shorts in the circuit)
Step 5: DONE!
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