Adtran TSU LT (CSU/DSU)
T1-FT1 Data/Channel Service Unit
The following table list the normal condition of the TSU LT (CSU/DSU) if any other condition exists take note of the LEDs and report it to Systems support staff. It is possible to check the history of errors this should only be done at the direction of System support staff.
| LED | PWR | ERR | ALM | TEST | TD | RD | RS | CS |
| Nomal | on | off | off | off | on/blinking | on/blinking | on/blinking | on/blinking |
| Condition |