HP 8112A Operating, Programming And Servicing Manual page 178

5. Check that the case is isolated from the power-cord power-pins
in accordance with IEC & VDE. If a problem exists, it must be
investigated and fixed before proceeding.
6. Check that the correct line fuse is fitted.
7. Check that all safety covers are fitted.
8. Check that all inter-connecting co-axial and flat cables are
properly connected.
9. Check that all boards are properly fitted.
10. Check that the heatsink connections between the main board and
the front frame member are secure.
11. Inform Hewlett-Packard of any repeated failures of any of the
checks, or any other safety features.