Weird fuse arrangement

[Alex Eisenhut]

I have this Commodore 128 power supply I need to deep clean so I took it apart. It works fine, it's just filthy.

It has a user accessible fuse holder, you can see it on the bottom of the supply. But it's not what it seems.
 
First time I see an arrangement like this.

Did someone change their mind too late in the design, or is this some weird regulatory thing maybe?

It's made in Japan during the late '80s.

[UnijunctionTransistor]

In the background, on the photo where the bodged fuse appears, there is this ironic message of: “for continued protection replace only with the same type fuse”.

[macboy]

I can only guess but perhaps this unit was sold in a market where user replaceable fuses are not allowed for safety/other reasons.

[Alex Eisenhut]

The Commodore 1541 drive has a user-accessible fuse on the mains side.

This power supply fuse is on the 9VAC secondary. There's another fuse on the board on the other secondary that feeds the 5V switcher.

The 9VAC line is quite lightly loaded on the 128. Why put that fuse accessible but not the other one? I don't know what the logic is here. Just funny. At least it's cleaner now.