What is the Voltage and Amp rating on these MOSFETS ?

https://www.infineon.com/cms/en/product/power/mosfet/20v-300v-n-channel-power-mosfet/80v-100v-n-channel-power-mosfet/IRFB3077/productType.html?productType=5546d462533600a401533d34ce491e5f

Infinion bought IR (who's name is on that part).

Good caps, but you will have to just experiment with how much more current it takes before failure. You may have tons of margin left or be under margin already and it's just a big hill away from burning.
 
I found that link too but could not figure how to tell how many volts it will handle.

I am not to concerned to much with amps, it is higher voltage I am after, like 48 volt ( 13s ) or 52 volt ( 14s )
Pretty sure it would run on 12s . but if you have doubts let me know.



liveforphysics said:
https://www.infineon.com/cms/en/product/power/mosfet/20v-300v-n-channel-power-mosfet/80v-100v-n-channel-power-mosfet/IRFB3077/productType.html?productType=5546d462533600a401533d34ce491e5f

Infinion bought IR (who's name is on that part).

Good caps, but you will have to just experiment with how much more current it takes before failure. You may have tons of margin left or be under margin already and it's just a big hill away from burning.
 
75v FETs, but you need margin for ripple and spikes, maybe 60v is reasonable and maybe 70v if you're hot rodding and don't mind things failing randomly.
 
The ratings of the fets, caps, etc don't mean a controller can be used at those ratings. It depends on what it was designed for, and what you're willing to do to beef it up if you want to go too much past that design limit. If you don't care about reliability you can push them really hard; it just makes it more likely that at some point they'll blow something up at one of those pushing moments. (in my experience, just when you need it most :oops: ).


There is a limit for the current, and it depends on how well all the FETs share, and how well they are driven by the gate circuitry, how much electrical noise, etc.

In a 6FET, there isnt' any sharing--each FET *is* the limit.

Also, the FET (phase) current is NOT battery current--battery current will be less, usually by quite a bit.


So with the 3077s, despite their package limit of 120A, I'd guess you could get 30-40A *battery current* out of the controller as a whole, max. But that depends.....


The limiting factor for current is often really heat--how fast can you get the heat out of the parts, and then how fast can you get all that heat out of the controller. Most controllers have a multistage heatpath, from FET to mounting bar, from mounting bar to controller case (some have even more stages, few have less). Each added stage means it's harder to get the heat out quickly. Most dont' have a good flat fit between the moutning bar and the case, either, no matter how tight you get the screws, and slathering more thermal paste in there doesn't necessarily make it any better (might for a while till it dries out then it's worse). This is less of a problem for 6FET controllers than bigger ones, as the bar is shorter and less likely to be bent along it's length somewhere; similarly the case is shorter and less likely to have a non-flat spot along the bar-mating-surface.

And the longer more heat stays inside the case, the harder it is on the ohter parts, especially the metal can capacitors--they lose their electrolyte and then don't do their job of smoothing out voltage and current so then other parts get worked harder and get hotter faster and then fail (often dramatically).

So...you can guess that you might be able to run a typical ebike cotnroller at twice it's rating for short periods, maybe 4-5 times that for very short bursts (a second? two? depends) as long as it isn't getting too hot at the various components inside. The higher you go, and especially the longer you do it at a time, the harder it is on everything in there.

If the controller says it's an 800w controller, you could probably put 1600w thru it for short periods, and maybe 2-3kw for very short bursts, as long as it has time to cool down afterward before you do it again--and the quicker it cools down the better. I've got this exact situation on my SB Cruiser trike with a 15fet (and a 12FET), and the controller stays pretty warm during a ride because of stop/start traffic. If I was pushing it like that the whole ride instead of just the stops/starts, it'd probably have already blown up. :)


So for a 6FET, I'd say you probably have a good chance of maxing it around 1000-1200w, for short periods and keeping it continuous at around half that. So if it's a 14s pack, call it 12A continuous, 25A short term, 40-50A very short burst.

You might get a lot more out of it, depending on the rest of the controller design, and how well heat gets out of it.

And how reliable you need it to be.



FWIW, I had a 6FET Lyen controller that I blew the caps up on more than once, usually when it was being pushed hard (beyond it's original design limits, but well within the Lyen specs). Thankfully it didn't pop the FETs, and new caps always fixed it. But it got hot quickly, and couldn't shed the heat easily, especially inside, so I ended up leaving the endcaps off, and that stopped the cap-blowing.
 
Right, the amp rating of the FETs doesn't determine the amp rating of the controller. There are a lot of other factors.
I'd guess that one should be able to handle 20A continuous if it has good cooling.
 
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