EXFO FTB-500 (Window XP) - Manual (Page 281)

Troubleshooting
FTB-500 271
LED Indicator Color Codes
LED Color and Status Message
Battery (external
power not
connected)

Not lit

Yellow

Yellow,
blinking

Red

Above LOW charge level

LOW charge level

Module and platform could be using more
power than what is available from the
batteries at any time. Connect AC power
as soon as possible.

Battery error
Laser

Red, blinking

One or more laser sources are on.
Alarm Varied

Each application using the Alarm LED
provides its alarm level to the platform
when needed (Red/Yellow/Green/OFF).

If more than one application uses the
alarm LED, the LED is displayed using the
color of the most severe alarm with red as
the most severe, followed by yellow and
finally green.

If more than one application uses the
alarm LED, the LED is blinking.
Remote Control Green

Unit is controlled remotely.