Uses for 150-300 amp transistors?

They can be used as switches, but are also used as current controlled amplifiers - a small current into the base controls a much larger current through the collector and emitter, giving current and voltage gain, with a load placed between the collector and the supply.

Leon

Thanks.

In other words, two if these guys could be used to build a large single phase inverter, IF I find a way to control them properly with small current.

And six of them could be used to make a phase converter, if I also use at least 2 isolation transformers.

First pair -> phase 1 Second pair -> isolation transformer -> phase 2 Third pair -> isolation transformer -> phase 3

Phases 1, 2 and 3 could have one side of each joined together to form a neutral. All I have to make sure is that the signals to the transistors to switch current, should be offset by 120 degrees.

Is that right?

Something like that should be feasible. I'd try designing a low-power version first, with small Darlington transistors - less dangerous and expensive if you blow something up.

Leon

I cannot tell the difference (and will appreciate clarification), but some are indeed SCRs. I have no idea what is an SCR. I do not want to post model numbers, so as not to make an impression that I am trying to sell this stuff here.

It's a Darlington transistor pair designed to reduce the amount of drive current needed to control the main circuit. This one has a minimum gain of 75, so you need about 4 amps of base current to switch the main load. But note also that it has a forward voltage drop of 2 volts, so at full load (300A), it will be dissipating 600W of heat -- better have a serious heat sink attached.

These modules require s> After pillaging my UPSes, I am left with a few 150-300 amp

I still have heat sinks for them. Big heavy ones. Also very many fans.

thanks.

Got it. Thanks.

Aside from their suggestions--- an active load for testing car batteries. Maybe an induction heater, but that's a bit too high frequency probably. Control for DC motor (eg. electric vehicle). Or perhaps as part of a dynamometer (using it as a load on a generator).

Best regards, Spehro Pefhany

Indeed, a great way to load down alternators, etc. I have 2 such units at work...

I already have a real alternator testing kit (load bank), 12/24v, military surplus. Could not sell it on ebay and decided to keep for the future, just in case. Good for at least 100 amps.

Funny how I knew who posted this just by reading the text, before looking at the "From:".

It sounds like they are from a large online UPS. They're probably MOSFETs if they are black rectangular boxes or SCRs if they are have a giant threaded stud on them. What sort of UPS are they from?

Ignoramus17647 wrote:

From a big data general 60 amp UPS, 1 ferrups 3 kva UPS (to be converted to a meat smoker), and 2 clary 5 kva UPSes.

Some are IGBT, some are rectifiers, some are SCRs, and some are rectangular mysterious thingies that weigh over a pound each.

That datasheet is a bipolar transistor, with switching times (from

:>

:> Ignoramus17647 wrote: :>> After pillaging my UPSes, I am left with a few 150-300 amp :>> transistors, rectifiers etc. I am curious, what could they be used :>> for, besides being in a UPS. I am especially curious about the :>> transistors. The rectifiers are of more obvious nature. I tried to :>> read about them, but it was some gobbledygook to me. :>> :>> One pdf for one such transistor is at :>> :>>

I agree but high voltage, high energy projects are not for the beginners.