EXFO FTB-2 - Manual (Page 31)

FTB-2 and FTB-2 Pro 21
3 Getting Started with Your Unit
Grounding Your Unit
When you perform outside plant tests with certain modules, you may want
to ground your unit because it can be exposed to overvoltages from the
telecommunication network. Refer to the user documentation that comes
with your modules to know if you need to ground your unit.
Note: To ground your unit, you need a grounding wire (18 AWG minimum) with a
U-shaped terminal.
W
ARNING

Not grounding your unit when it is recommended may cause
serious injuries to communication network staff or other users.

Ensure to ground the unit using a grounding method that
complies with your local regulations. If you are not sure on how
to proceed, consult a certified electrician.