How to Make an Airsoft Mosfet

This link from higher up is what I'g using equally a guide: http://unconventional-airsoft.com/2009/08/26/how-to-make-a-basic-mosfet-switch/

And that's pretty much the mosfet I'm using other than it's likely a clone of information technology based on my reading, since I bought it on ebay. Knowing likely it would be a clone but it was cheap and I figured I'd requite it a try on this application.

And then oestrus wise, with an eleven.1v lipo information technology was getting hot enough to melt solder connections so too hot. Fairly surprisingly it didn't seem to harm the mosfet itself. Merely I'm still waiting on 100ohm one/4w resistors to test and run into if that is somehow causing the oestrus issue. With 7.4v it seems to get hot but not hot enough to worry about, I didn't take time to hitting it with the IR temp to come across what it was actually but felt adequate.

I absolutely don't understand how that mosfet works, IE I don't know the reason for the various values of resistors etc on which leg and why. I exercise know running a college resistor on the leg in place of the 100ohm caused information technology to cycle very irksome similar information technology was running on around 5v or something around that range. So I'yard not sure how the magic in the mosfet converts voltage etc, just since I don't have the correct role I'1000 sort of assuming that'due south the event. Once I get the resistors(hopefully today), and run across if that solves information technology or not. If not then my next guess would be the 3034's I got aren't whatever adept. Though I might accept and try each of them since from what I empathise if they don't switch entirely then they tin cause excess heat to be generated.

Luke

EDIT: Alright did a bunch more testing this evening and I call back I've drawn some conclusions which may or maynot exist correct.

And then the 100ohm resistor from what I can tell merely drops the voltage/amperage down for the gate on the mosfet to trigger. I found some guys who swear up and downwards that 3034 mosfet's don't fully open the gate until they striking 10v or so. So I pulled my resistor off the trigger line and redid my test. Same results mosfet still getting far too hot. And by too hot if I didn't mention above nosotros're talking the solder started to melt at the articulation. Without the IR temp gun handy I'm non certain what it was, simply freaking way too hot.

Now testing wise, what I did was shoot around 20 times on semi automobile. With the 11.1v that'due south enough to go the mosfet that hot which isn't correct. With the 7.4v it seems happy, warm/hot but non dangerous levels most what I had expected. And then my theory is that these are just garbage mosfet's that I got, the more I read the more I realized how crappy the knock off parts really were.

So I went ahead and ordered from digikey four IRLB3034's that I know are 18-carat and by then I'll have the 100ohm resistors since I'll kickoff with the build as the spec lists on the site. Simply if I find I'chiliad getting hot and so will I drop that from the excursion and attempt it the fashion information technology's wired now. I expect information technology's just bad mosfet'southward at this point, only information technology could also be wiring, but until I tin examination the new ones I'g just going to leave the wiring as is and effort a new mosfet in the existing circuit.

Then more info coming as I get more components etc. Only correct at present despite the set backs I'm cautiously optimistic. And I know at this point I could accept bought at least ane decent mosfet for the money invested, but I'one thousand still winning if I can make all this work. Since I've got a bunch of guns to install these in, and I've learned a boat load about how they work in the process which will go far much easier to diagnose and repair going frontwards.

« Last Edit: May 25, 2016, 08:44:13 PM by luke213 »

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xaos - "298,000 yen for a consummate gun. How much is that in real coin?"