It’s it a jst connector? You have a pic of what the connector looks like? I do have basic soldering skills so maybe i could solder directly on
JST, or just standard 2.54mm pin headers if you really want. I might able to supply those. Just need to be careful and make sure they are connected the right way. (Silkscreen is labelled).
Actually, if the JST connectors don’t arrive in time, I’ll just solder female pin headers and supply male pin headers.
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Sounds good. I basically just need to solder on xt60s right? Are you sending the prototypes out for free? Also you have a link to a fuse you would recommend to solder in line? The fuse is soldered onto the positive lead right? The only prob i might have is that it might Be a tad too big I’ll open my enclosure to make sure it will fit before your ready to send it out. what’s the approximate height of it?
Dimensions are 55 x 39mm
You will need to solder wires to the pads (and xt connectors to those wires)
By inlining a fuse, there are some inline fuse holders for ATC blade fuses you could use, or what I did is I got some auto-link fuses and using ring terminals, bolt the fuse inline.
I’ll send them out for free. They are prototypes after all. All I ask in return is feedback and test information.
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You have a link to a recommended fuse? Does the fuse go on the positive or negative leave? And before or after the switch?
Before the switch, doesn’t matter positive or negative, but I would recommend positive side.
https://www.arrow.com/en/products/142.5631.5702/littelfuse
These are the ones I’m using (I think) There are different amperage ratings. The bolt holes are slightly too small for 1/4" 20 bolts, so either #14 will work, or you could do what I did and drill it out.
Derp, the bolt holes are M5
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Okay, so I soldered together the first prototype.
Not sure what happened, but when I tried to spin up a motor, there was a loud POP and one of the drain pads was blown clean off.
The MOSFET was also arch-welded to the PCB.
The MOSFET also failed open-circuit, which is REALLY weird.
The ESC I was testing with is also dead, it’s a short circuit.
Did the switch kill the ESC or did the ESC kill the switch? The 70A fuse on the 10s lipos I was using is still intact. (It’s a slow blow automotive fuse)
The ESC was having problems prior, maybe the ESC died short-circuit, and then the switch saw a few hundred amperes and the single MOSFET I soldered on was like NOPE, K BAIIIYEEEEEEE.
EDIT: okay I think the short on the ESC killed the MOSFET. The exposed source pad on the MOSFET is a short with the drain pins, BUT the source PINS are open circuit. The ESC failed short, the few hundred amperes caused the MOSFET to fail short, but the MOSFET’s internal bond wires to the source pins to burn. Now the question is, was the ESC going to die on its own or did the switch do something to bring about its death?
I’m guessing it was the ESC, the ESC was having problems with having one or more phases being undriven. I’m guessing the gate on one of the MOSFETs ended up floating after being driven high, and shoot-through occurred.
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What if you try with a heating element as a load instead of an ESC? To eliminate any uncertainty.
Like, a straight capacitor, nothing else; then a straight heater/resistor, then both.
I’ll try a 10 ohm resistor once the primary MOSFET turns on.
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Good news, I tested with the 10 ohm resistor and a throw-away VESC.
Resistor got super hot.
throw-away vesc had no problems with FOC detection and keyboard input. I used modest current settings, ±20A everything, 6S lipo test pack.
Pretty sure the first ESC was on its last lengths, I heatguned the crap out of it xD. It’s too bad it took a nice MOSFET with it.
I’ll assemble the other two prototypes later this weekend and hopefully ship them out on Tuesday.
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I love smd soldering
Don’t ask about Q3
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What happened to q3
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Good work on the proto & debugging
On your next pcb, get a seringe of paste and hot air the whole thing, it will make it so much easier
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Thanks, but
I don’t have a hot air station reeeeeeee.
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SMD reflow is incredibly easy. You can use anything, oven,skillet. Give it a try and you will never go back. Order paste stencils with your boards.
In some circles, if you mention “skillet reflow” you’ll get an ass-kicking.
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If you don’t have hot air or a $50 mini oven, a skillet will work fine. An electric skillet at 100C helps with large rework as a preheater also. People can complain about it if they want, doesn’t mean it won’t work. Also,use leaded paste.
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Next tool on your wish list then. Even before an oven
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So, anyone still interested in testing out the two prototypes?
Also, I just checked the dead ESC, Phase B is a short between power rail and ground xD. Must’ve messed up a solder joint on one of the gate pins when I was reflowing with a heatgun.
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