User's Manual

User’s Manual for Node C Network Elements
Page 88
M0121A1A_uc.doc
SMA connectors have a specified torque of 100 Ncm. Use an appropriate tool to
fasten and unfasten these. Do no over tighten the connectors or screws. The table
below shows various screws with their respective torques.
Screw Type Tallow-drop Socket head cap Countersunk head
Thread size Specified Torque (in Ncm)
M 2.0 40 not in use 40
M 2.5 82 not in use 82
M 3.0 145 100 145
M 4.0 330 330 330
M 5.0 650 tbd. 650
table 6-1 Specified torques for various screw types
) Note: Depending on the configuration of the Node C the FRU can be
equipped with a 50-Ohm termination resistor. In such a case, use
the termination resistor of the old FRU to terminate the respective
connector of the replacement part.
) Note: After the replacement of a component, check whether the system
has to be levelled anew.
) Note: Do not forget to reinstall the front cover after the replacement
procedure to ensure safe operation.
If any FRU not contained in the following chapter needs to be replaced, contact
customer service for additional instructions.
6.2.1 Power Supply
• To remove a power supply,
first disconnect all cables.
• Unscrew the seven M4
socket head cap screws by
which each power supply
is fastened to the cabinet.
• Use these screws to fasten
the new power supply and
reconnect all cables.
figure 6-1 Power supply screws