PNP/NPN??? What are you talking about, this is a mosfet????? As for "Real 100A Fet", the specs should be taken with care. At 100A that mosfet will EXPLODE, it CANNOT take 550W of heat (100x100x0.055 from I^2 x 0.055 mosfet Rds) No way Hose!!!! BTW as you can see from the maths, VOLTAGE does not affect power loss as heat here! Something like an IXFK160N30T would stand a much better chance (it has 0.019 Rds and is designed for large heat transfer to a heatsink, so the now reduced 190w (at 100amps) is doable! Gat capacitance might be a problem, as SSR's are not exactly known for they high gate drive (or speed), and during the transistion there is a brief time of MASSIVE power loss (I am talking thousands of watts), so this must be kept short or once again the mosfet will EXPLODE!!!!!!!! :)
@@windpowerandmore6310 hauuuuhh???? I know what they are, and they are NOT a mosfet, ....what are you saying???? fiy I am a retired electronics design engineer, I do know what I am talking about most of the time :)
These SSR's seen here seem to be a real "CON JOB" by the manufacturer , a TO-247 device package shown here can handle it's I^2R power dissipation only with an adequately sized & cooled heat spreader/heatsink..( the one shown looks inadequate.. 2) D/S leads must be as short as possible 3) gate drive of 3 -7 volts is inadequate..it should be 10-15 volts at least... 4) for better understanding of such high power device packaging & power handling please see the internal construction of power modules (70-200Amps) of reputed device manufacturers like .. SEMIKRON , TOSHIBA , SIEMENS, FUJISTU , etc. & related application notes.
I know all that and I agree with you. You'll also see in the video I said I wouldn't put 100amps through it even with the real 100a fet . I also trigger with 12v minimum
If you read into the specs for these SSRs, as the current capability goes up, you need more then just the air cooled heat sink. They require water cooled heat sinks. I was looking for a 50amp relay, and that required water cooled. I was looking for a TRIAC type, for AC switching. But the cheap chinease copies are no where capable of the marked current.
@@windpowerandmore6310 RU-vid randomly suggested your video. I was hoping you were fixing the TRIAC type. My application was to use an SSR for a minisplit, to cycle power with a timer. The local power company adopted a KWHr price per time of day. From 4pm to 10pm, it's over $.16, and that's only going to get crazy in the future. No clue where all the green energy for charging vehicles is going to come from. At any rate, I shut the AC/HP down during that time. Some thermostats support time off on a clock. Not this unit, and it requires a custom thermostat, just two wires with DC and diplexed digital on top of that. So to fix that, use an external timer that 'unplugs' the power with a relay. This is a 42KBTU, with 50amp requirement, and reading up on the SSRs, found they need water cooling at that current. Gee's who's going to add that complexity to a relay? Not me! The FOTEK branded SSRs from eBay are mostly counterfeit from China, and need a 50% derating. I did burn one up, 40amp. It was running a 3KW radiant heater in the shop. I have them as dual, as well a mechanical thermostat in series as a high-limit as I don't need a shop fire.
