Troubleshooting guide

Section 4, Site Preparation - Electrical Considerations
61186003L1-1D 4-3
ELECTRICAL CONSIDERATIONS
The MX2820 shelf supports dual-feed –48 VDC or ±24 VDC power inputs.
Power Wiring and Fusing
MX2820 power connections, including return connections, should be provided from the fuse
panel using insulated wire and the appropriate fuse (see Table 2-7 on page 2-6). Per appli-
cation requirements, power can be provided by a –48 VDC or ±24 VDC supply. A separate wire
should be run from the fuse panel for each –48 VDC or ±24 VDC input and for each VDC
return. Power wire with red insulation is recommended for the voltage feeds, and power wire
with black insulation is recommended for the return feeds.
NOTE
Applications which include STS-1 multiplexers should be –48 VDC
only.
Fan Module Power
Refer to the appropriate Installation and Maintenance Practice and/or Job Aid for Fan instal-
lation.
Frame Ground
Each MX2820 shelf requires a connection to frame ground using the appropriate AWG wire
size. See Table 2-7 on page 2-6.
FOLLOW-UP PROCEDURES
Once the Central Office preparation described in this section of the manual is complete, the
MX2820 shelves are ready for the installation. “NTP-001, Shelf and SCU Installation” provides
the instructions for installing the shelves.