EXFO FTB-9100 for FTB-500 Optical Switch - Manual (Page 13)

Getting Started with Your Optical Switch
Optical Switch 7
Inserting and Removing Test Modules
7. While applying slight pressure to the module, turn the retaining screw
clockwise until it is tightened.
This will secure the module into its “seated” position.
When you turn on the unit, the startup sequence will automatically detect
the module.
Turn retaining screw knob
clockwise
FTB-500 left panel