Specifications

7-14 Cisco MGX 8220 Reference, Release 4.1

Connecting Power for DC Systems

These sections describes how to connect DC power to the MGX 8220 shelf.

WarningThe power to the shelf is OFF at this point. DO NOT apply power by pressing the black button until

later.

DC Power to the Shelf

DC power is connected as described in the following steps.

Step 1 Press the red button on each power entry module (PEM) so their black buttons are in the

out position. This opens the circuit breakers in the power entry modules.

Step 2 Each power entry module has a EURO Block 3-pin male power receptacle for connecting

the 48VDC power sources. The mating female connector is supplied by Cisco with the

power entry module.

Figure7-9 48VDC Male Power Receptacle Viewed facing the Rear of the Shelf

Step 3

Attach the two supplied female EURO connectors to the two cables supplying DC power

to the power entry modules. The cables should have three insulated number 12 AWG wires

(solid or stranded) with the insulation stripped back 0.25 inch (6mm) on each wire.

Test which way the female connector attaches to the male connector using the pin

assignments in Figure7-9 as a guide. For each cable, insert each of the wires into their

correct holes in the connector and secure each wire by tightening the screws in the

connector.

Step 4 Connect a cable to each of the power entry module connectors. The connectors are

polarized so they cannot be inserted the wrong way.

Step 5 Use the PEM cable clamp to secure the power cable. (See Figure7-10.) Place the cable

clamp over the connector so the small hole is positioned over the boss on the PEM. Secure

by attaching the clamp to the PEM with the captive screw. The cable clamp can be dressed

to the left or right and secured to the clamp using a tie wrap.

Step 6 If the redundant PEM module is not used, the Cover Power Entry Module must be installed

in the empty position to assure proper cooling of the rear cards.