EXFO FTB-200 v2 Compact Modular Platform - Manual (Page 188)

Maintenance
178 FTB-200 v2
Recharging the Main Battery
To recharge the main battery:
Connect the unit to a power outlet using the AC adapter/charger. The
charge cycle will start and end automatically.
I
MPORTANT

Batteries are not charged at the factory. Fully charge them
(about 3 hours) before using the unit for the first time.

The time required to charge batteries depends on various
factors such as the type of modules currently in use and the
ambient temperature.

To ensure that batteries function or charge properly, keep them
in temperatures between 10 °C and 40 °C (50 °F and 104 °F).
Store below 50 °C (122 °F).

Depending on the way the unit is used, after a while, the charge
status icon may no longer correspond to the actual power level
of the battery (for example, icon indicates that power level is
sufficient, but unit turns off because battery is too weak). A
complete calibration cycle will be necessary (see Recalibrating
the Battery on page 179).