Norman P400D problems

I have an old P400D power pack which blows the main fuse whenever it is triggered... Anyone have experience with these, or this problem?

This has been sitting around quite a while & a friend is looking for an affordable small studio system.

I'm thinking I might take this to a repair tech, if the repair wouldn't be too spendy.

I've owned a P800D and P2000D and haven't had that problem, but it's either a short, or you don't have the right fuse. You could check with Photo-Control (which owns Norman) or a place like Flash Clinic in New York to confirm the fuse type.