AC blowing fuse

My condenser fan fuse (7.5) keeps blowing soon as blower+ac is activated in on position Any ideas?

disconnected condenser, still blows
disconnecting compressor power stops the fuse from blowing
always in on position, doesn’t matter if the car is running.

It was told it was a almost new compressor, but it sat for like 5 years. I loaded it with freon to 28lbs instead of the recommended 32-34 (ran out), the ac ran great for about 4 hours Then I turned it off for like 5 minutes, now it just blows fuses.e

No one has any input on this?

I’ve heard the compressor could be doing this internally (short in coil or switch)
Anyone know a good way to diagnose this? I have a multimeter.

Check the resistance in the compressor… Switch the multimeter to ohms and make sure the compressor has no power going to it take ur 2 leads one to ground and other to power …find the allowed resistance for the compressor if u get a “ol” or blank reading your compressor has an open or a short which will lead u into buying a new compressor