Connect Power to a DC-Powered Router

Connect DC power to the router by inserting power cables from external DC power sources into the quick-connect terminals on the faceplate of each power supply. Power and grounding cables are not supplied with the router. For information about the required cable type, see DC Grounding, Connection, and Cable Specifications.

The router must be connected to at least two separate external DC power sources.

There is no standard color coding for DC power cables. The color coding used by the external DC power source at your site determines the color coding for the leads on the power cables that attach to the terminal studs on the power supply faceplate. You must ensure that power connections maintain the proper polarity. The power source cables might be labeled (+) and (–) to indicate their polarity.

To connect DC power to the router, follow this procedure (see Figure 25:

1. Verify that there is no power flowing from either external power source, so that the voltage across the leads of the power cables is 0 V. Ensure that there is no chance that the cable leads might become active during the procedure.
2. For each power supply, verify that the power switch on the power supply faceplate is in the OFF (O) position.
3. Connect the grounding cable to a proper earth ground for both external DC power sources, if it is not already.
4. Verify that a licensed electrician has attached the cable lug provided with the router to the grounding cable.
5. Using a Phillips screwdriver, remove the screw that is next to one of the grounding symbols along the upper edge of the chassis rear. Secure the grounding cable lug to the chosen grounding point by reinstalling and tightening the screw.
6. If necessary, strip a short section of the protective cladding from the end of each power cable so that the metal core can come in direct contact with the quick-connect terminal.
7. Thread the power cables through the hook located on the faceplate to the right of the quick-connect terminals.
8. Insert the exposed end of each power cable straight into the appropriate quick-connect terminal:
   • Insert the positive (+) source cable into the return terminal, which is labeled RTN.
   • Insert the negative (–) source cable into the input terminal, which is labeled –48V.
9. Using a 3-mm flat-blade screwdriver, turn the screw on each quick-connect terminal clockwise to tighten the terminal connector around the cable.
10. Verify that the DC source power cabling and the grounding cabling are correct, that they are not touching or blocking access to router components, and that they do not drape where people could trip on them.

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