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Spoon
2006.06.16, 10:10 PM
I have compiled a short but comprehensive FET guide that will hopefully answer a lot of questions. The excerpt below comes from a more detailed article (http://mini-zracing.com/blog/_archives/2006/7/11/2093568.html) posted at mini-zracing.com (http://mini-zracing.com/blog).

A stock Mini-Z circuit board has two FET chips that control the motor. The FETís will be located close to the motor terminals and probably near a big black bock on the circuit board.

Every FET can only pass so much current before it overloads and burns out. You can overload a FET by using a motor that draws too much current or by overloading your drive train. If you hold the throttle down while you are against a wall or you are trying to tow something with your Z, you can easily blow the stock FETís. Basically if you ask too much from your car, you risk burning out the FETís...

The remainder of the article addresses the following topics.


Which FETs do I have?
How do I know I have a blown FET
What if I blow my FETís and/or I want more performance?
Do I need a FET upgrade?


Enjoy and feel free to leave a comment on the article.

briankstan
2006.06.20, 11:54 AM
you might just want to add that some "stock" forms of racing don't allow for upgraded or fet stacking.

great work.

imxlr8ed
2006.06.20, 06:01 PM
IRF is pretty helpful in understanding more than you want to know ! :o

http://ec.irf.com/v6/en/US/adirect/ir?cmd=catNavigateFrame&punchInID=71

Here's the PDF of those 7317s I used to use... actually, I'm pretty sure a few of the others listed would work as well, still looking for the 3010's info.

Lotta learning to do myself... current questions:

Do fets only operate within certain recieved "signal" parameters ? (is this the ID channel column ?) Is the rating shown a minimum... ? Somebody smart... please help ! It would be very cool to know exactly what fets are compatible with the Zs... I have a feeling it's all been guess work up until now. (or has someone already gone through this process ?)

imxlr8ed
2006.06.20, 06:12 PM
Whoa... diggin deep now !

http://www.me.sc.edu/courses/emch367/Download/Func_bx/mosfet_edited_Brian.doc

imxlr8ed
2006.06.20, 06:29 PM
For example, how do I know if something like this would work ?

8 volts ! 3.0 amps... interesting !

imxlr8ed
2006.06.20, 06:42 PM
Aha !!! Think I found the 3010s... they're Hitachis apparently.

imxlr8ed
2006.06.20, 06:48 PM
Are these the 3004s as well ?

Sorry I'm dumping all of this on here... just trying to find where to get the 3010s, and if I can't get them, what is comparable?

sciencemike
2006.06.20, 07:33 PM
Yes imxlr8ed, the 3010's are hitachis. Not IRF. I had ph2t tell me that same bit of trivia a few weeks ago. BTW, i took my 3010's off my AD board, in lieu of a nelly. So they are up for sale, dont know right now for how much. But i have 4 of them..

Mike