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AimTrack with recoil - Failed MOSFETs?
p4lmore:
--- Quote from: AndyWarne on September 01, 2017, 06:04:51 pm ---
--- Quote from: p4lmore on August 30, 2017, 06:32:45 pm ---Yeah, I sent Andy an email a few weeks ago and followed up originally with a post on MAMEWorlds Ultimarc Forums.
I haven't seen any replies on either venue yet, so hoping someone may have an idea here =)
--- End quote ---
If we received an email of this type I would definitely have replied. So I can only conclude that the email didnt reach us for some reason. We can help with repair or replacement. The Mosfet is a 33N10 though.
Can you re-send the email?
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No worries at all but, it came from my hosted email, so most likely caught up in a filter or otherwise somewhere, I'll re-email from my gmail.
The guns I picked up from an eBay seller with the recoil kits added, at the start of this year (when I rebuilt my arcade with my income tax return lol) and since it happened during a storm, wasn't sure it would be viable for a replacement.
I will say, I've replaced the MOSFETs in 1 and still no joy, though the original ones had turned somewhat brown and when powered got EXTREMELY hot to touch.
Either way, I'll shoot you a line.
Thank you very very much, I love your products and I've always had amazing service.
Thank you.
lilshawn:
I'd be looking upstream at whatever is switching on the FET. sounds like it's getting held on partially. if it was on 100% the coil would fire and the fet would likely burn up in a flame ball within a matter of 30 seconds.
i'd suspect a snubber diode and/or a pre-drive transistor.
p4lmore:
--- Quote from: lilshawn on September 02, 2017, 01:31:02 am ---I'd be looking upstream at whatever is switching on the FET. sounds like it's getting held on partially. if it was on 100% the coil would fire and the fet would likely burn up in a flame ball within a matter of 30 seconds.
i'd suspect a snubber diode and/or a pre-drive transistor.
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Awesome, thank you!
I haven't had a chance to power them back up and take the meter to them yet. I've only begun work on one thus far, the other is still untouched.
I will say, when I first hooked them up, the actuator would click repeatedly (and very rapidly). When I first looked at the fets they were HOT, I mean I brushed my finger across it and burnt it bad. The metal on the FET is actually discolored from the heat. Hence the first inclination to replace those.
Hopefully this weekend I can find some time to probe around abit and see, but sounds like I need to start on the higher voltage out side of the MOSTFET with my probe and start checking the diodes etc up to the linear actuator eh?
Thank you
samslack:
Any ideas of a replacement Moffett that part is listed as obsolete and not available. My solenoid just keeps triggering. It stopped working all togather and it was a bad wire in the usb cable I ran a separate wire now it fires but continously. Would love to fix this. Any other sources for these boards or mosfets ?
lilshawn:
FQP33N10 replacements
IRL540N
FQP33N10L
BUK7515
BUK7520
BUK7526
BUK7528
BUK7535
BUK7540
2SK3216
2SK3218
2SK3586
2SK3590
2SK3644
2SK3920
i would start with the IRL540N (dont worry about any of the letters after... they often just designate lead free variants or parts that come on a spool or tape. IRL540NPBF or IRL540N) i would probably steer away from the "IRL540" if you could as it's internal resistance when on is slightly higher than the original part, but in all honesty, it's probably fine. it's just a solenoid and not super critical. it might mean it heats up slightly more than the original if it's being used extensively. probably a fraction of a degree. (The IRF540N also has a lower than original maximum on-resistance which is 0.044 ohms, while the IRF540 is 0.077 ohms. the original part resistance is 0.052 ohms)
or try the FQP33N10L "L" variant of the original if you can get it.
also search for part numbers containing just "33N10" it may have different letters before it chosen by the specific manufacturer and the same part may have something different.
these listed above are all pin compatible parts numbers... some of these will be the same or better than the original (higher current, lower resistance etc) but may or may not be suitable for your application. try these at your own risk of course. but for the sake of a dollar or 2 it can't hurt to try. worse case it blows up again and you end up back where you are.
your board or solenoid should have a diode ... like a 1n4004 or similar, it's probably a good idea to change it as well. it snubs back EMF pulse from the coil when it shuts off...this pulse can kill MOSFETS if it's leaky or broken.