AT&T 3551 Switch User Manual


 
COMSPHERE 3550 Series Data Service Units
3-4 February 1995 3550-A2-GB20-10
Table 3-2
Model 3551 DSU Jumper Straps
Strap
Designation
State of
Jumper Strap
Function
J12 Left V.35 Test Mode Indication:
Left
— Enables V.35 Test Mode Indication (Pins 1 and 2).
This is the
factory default.
Right
— Disables V.35 Test Mode Indication (Pins 2 and 3).
J13 Left EIA-232-D Test Mode Indication:
Left
— Enables EIA-232-D Test Mode Indication
(Pins 1 and 2).
This is the factory default.
Right
— Disables EIA-232-D Test Mode Indication
(Pins 2 and 3).
J20 Left Alarm Monitoring (used with the –48 Vdc Central Office Power Unit):
Left
— Disables the –48 Vdc alarm monitoring function
(Pins 1 and 2).
This is the factory default.
Right
— Enables the –48 Vdc alarm monitoring function
(Pins 2 and 3); the NMS adapter cable is being used for alarm
monitoring.
J21 Right Alarm Monitoring (used with the –48 Vdc Central Office Power Unit):
Left
— Enables control of alarm monitoring via the NMS adapter
cable (Pins 1 and 2); the NMS adapter cable is being used for alarm
monitoring.
Right
— Disables control of alarm monitoring via the NMS adapter
cable (Pins 2 and 3); a standard EIA-232 cable or the NMS adapter
cable is being used for the diagnostic channel.
This is the factory
default.