EXFO FTB-2 - Manual (Page 19)

Introducing the FTB-2 and FTB-2 Pro
FTB-2 and FTB-2 Pro 9
Power Sources

Lithium-ion rechargeable batteries (automatically take over if you
disconnect the unit from its external power source). The number of
batteries that power your unit and that come with it depends on the
model that you have purchased. The table below gives detailed
information.

Possible to switch from an external power source to battery power
or vice versa without affecting operation.

The battery recharges automatically when the unit is connected to
an external power source (with the AC adapter/charger).
Note: When the ambient temperature is below 0 °C (32 °F) or when it reaches or
exceeds about 40 °C, the batteries can either charge more slowly than
usual, or not charge at all, depending on the internal temperature of your
unit.
For more information, see Electrical Safety Information on page 16.
Model
Number of batteries
that power the unit
Number of batteries
provided with the unit
FTB-2 1
Battery must be inserted
in the first battery slot
(use the markings at the
back of the unit to guide
you). The second
battery slot does not
power the unit. It only
serves as storage for an
extra battery that you
would swap in the first
battery slot when
required.
1
You can purchase an extra
battery and store it in the
second battery slot.
FTB-2 Pro 2 2