Originally Posted by quinten
Possibly because
the fuse at the battery isnt the only ground point ... so doesn't break all connections
whats not shown on the diagram is
the old finned rectifier had its own ground .

Originally Posted by john healy
... and suggest that the fuse should have been put on the ground side of the battery. Well, in 1966 they did just that, but they discovered: if the fuse failed while the bike was running the bike would keep running and damage the rectifier. The next year they change the harness with the fuse on the feed side of the battery

I don’t understand that. I probably need Stuart to explain it!

Yes, a bike can keep running on the charging system with the ignition switch on and the battery isolated, such as by a blown fuse. I don’t see what difference it can make whereabout the battery circuit is broken: near the live terminal or near the return terminal.

I must take a look at the later Triumph diagrams.