Fuse keeps blowing

HDRchampion

Before you sell me something, ask how well my baby
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So i got a new power supply on ebay & was working...I tried the adjust the voltage & then i blew the fuse. I ended up ordering 250v 4A fuse which i think is the same as the previous fuse but keeps blowing too.

Not sure if i have the correct fuse or not. If i do what can be causing the issue? This is for an Astro City PSU.
 

Xian Xi

JammaNationX,
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Sounds like a short. Most PSUs don’t pull more than 3A on the mains so if it’s blowing at 4A I’m guessing there’s a short.
 

HDRchampion

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Does Slow/Fast Blow fuse make a difference? This is probably dumb but how do i go about looking for a short. Never had an issue with any of my cabs before.
 

titchgamer

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Disconnect everything from the PSU then try it again.
If it blows the fuse again its a fault with the PSU.

If not then its something further down the line.
 

HDRchampion

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The PSU fuse is the one that is blowing...
 

Xian Xi

JammaNationX,
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The PSU fuse is the one that is blowing...

Correct but like mentioned, disconnect everything and power on then one by one attach things back to the PSU and see if/when the fuse blows. And stick with fast blow. Slow blow is for other things.
 

MKL

Basara's Blade Keeper
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check the bridge rectifier.
 

HDRchampion

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Disconnect everything? As in everything that has quick disconnects?
 

titchgamer

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As in everything thats on the output side of the PSU.

Once all the outputs are disconnected power it up and see if its ok or not.
If it blows again the PSU is duff.

If not reconnect the outputs one at a time and test to see if it blows.

This will narrow it down to one circuit.
Remember to connect any shared grounds first.
 
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