Below you can watch the video from test number five with Huntkey Green Star LW-6550SG.
What exploded were the two switching transistors. When the power supply explodes it means that the primary side is under dimensioned. When the secondary side is under dimensioned the power supply dies silently, because when a rectifier burns the short-circuit protection enters immediately in action shutting down the power supply.
So Huntkey should have used more powerful transistors and added a heatsink to the rectifying bridge, plus using rectifiers with higher current limits for the +12 V output.
Below we have some pictures of the power supply and the switching transistors after the explosion.
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Figure 19: Huntkey Green Star LW-6550SG after the explosion.
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Figure 20: Huntkey Green Star LW-6550SG after the explosion.
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Figure 21: Huntkey Green Star LW-6550SG after the explosion.
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Figure 22: Switching transistor after the explosion; see how it cracked.
