Tuesday, March 16, 2021

Problems with 5 volt 15 amp AC Adapters

 I have been having Problems with 5 volt 15 amp AC Adapters.  Three of them have died in the last 2 or 3 months.  I opened them up and the capacitors are blowing up.  I have been looking for a solution for a while because they run too hot.  I use them to power my signs and the sign is limited in brightness so it only consumes 12 amps.  In fact I have powered one LED sign with a 10 Amp AC adapter for a few months with no issues other than a warm AC adapter.  Recently I went on Amazon instead of eBay and found a better 5 volt AC adapter!  Here is the ad on Amazon:


The advertisement even shows the insides of the Ac adapter to show how it is built better.

This next picture shows the insides of the dead adapters. You can see the blown capacitors.  One of the power supplies from Amazon is shown on the left so you can see the size difference.


I replaced the capacitors and two out of three power supplies are working again.  I think a bigger issue is the choke coil that is usually in series with the output of a switching power supply is missing.  With the coil removed, you are pulsing say 10 volts into a capacitor to get an average of 5 volts out.  This is hard on the capacitors making them run hot.






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