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30v power suppy problem

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cobra974life

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hope i did this post right but i have a vap-5a30v2 regulated power supply,it old cant find any info on this at all,but the problem im having is when u turn it on it instantly goes to 48+ volts ,i cant do anything with ajustment knobs, the fuse blew i replaced it ,and this is the resaults i got, i checked diods and resisters and transformer all is good ,it has a relay switch could that be bad,but i here it clicking when u turn the power on.from the secondary off tranformer 5 wires that plug into board orenge has 36.4 volts red has 19.5 and 13.6 with ground as green wire the other reading were brown wire as ground.
 
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The relay is meant to switch the input voltage down as you reduce the selected output voltage. So when the PSU output is between 18V and 30V it uses the 36.4V, when its between 11V and 18V it uses the 19.5. When the output is less then 11V it uses the 13.6V.
There is a series transistor between the selected voltage and the output terminals it looks as though its short circuit.
Frank
 
ok ill check that i dont mean to sound stupid but is there a way to test transistor to tell if it is bad
 

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