Testing Procedure

Using a 12V source and a automotive 12v light bulb:

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• connect negative to Source(S)
• connect voltmeter as shown
• connect the + side of the voltmeter to Drain (Bulb should be off)
• connect the + side of the voltmeter to Gate (will activate the mosfet)
• connect the + side of the voltmeter to Drain (Bulb should be ON)
• record voltage

Testing IRFP260 (Fake)

Measurements

Voltage: 12.09v

...

R(ds) = 0.055 ohms

Result

FAKE!

Testing IRFP260 (Real)

Measurements

Voltage: 12.06v

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