Which Mosfets
Which Mosfets
Can someone please tell me which mosfets I need for an Ali Express 1000w grid tied inverter. I have 2 blown, they have no numbers on them. The mosfets I have give a different reading.
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Re: Which Mosfets
Different reading than what?
If they have no markings, are you certain they are MOSFETs? There are a number of different kinds of parts that come in the same component packages that FETs do, and some of them are used in similar applications.
Some parts may appear to have no markings, but actually have lightly laser etched markings on them only visible at the right angle and lighting.
Some may have had them ground off to make it slightly harder for another company to copy their stuff, or to repair (so you have to buy new ones), or to hide that they used insufficiently-rated parts for the purpose, or counterfeit parts, etc. Those you don't have much chance of figuring out what they were.
To find compatible FETs you have to know the voltage they must handle, worst-case maximum peak, and the current they must handle, worst-case maximum continuous.
Without knowing what the originals were rated for, you might be able guesstimate from the unit ratings.
How much voltage is the unit rated for, maximum?
How much current is the unit rated for, maximum?
How many FETs are in parallel (to divide that current to guesstimate a rating)?
Also, if you use FETs that have different ratings (especially RDSon) and potentially the gate (Qg, etc) ratings and switching times, etc., the original FETs and the new ones won't share current as well as they were designed to, so either the new ones or the old ones will take more load than they should, and further failures may occur.
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Re: Which Mosfets
The fets in the inverter have a different reading to all the ones that I have in my toolbox. I was hoping that someone had the part number as these must have been replaced many times 9n these inverters.
If not I will take the longer route to get the info.
If not I will take the longer route to get the info.