The Supertester 680 R contains a glass fuse (typically 0.5A / 250V) to protect the current circuit.

Leo downloaded it. The file was 847 pages long, but the first 600 were blank. Page 601 began:

in Milan, Italy. Renowned for its precision and durability, it has been a staple for electronics professionals since the 1960s and 1970s. Manual & Documentation Resources

Session 4 — Maintenance, Troubleshooting & Safety

You can find and download the through the following digital libraries and technical repositories:

You can find various editions of the PDF manual and schematics online: