Connecting Dc Power Supplies With Power Sources - Cisco Nexus 7702 Hardware Installation Manual

Connecting DC Power Supplies with Power Sources

Warning This product relies on the building's installation for short-circuit (overcurrent) protection. Ensure that the
protective device is rated not greater than:
250V, 20 A
Step 4 Turn the power supply switch from standby to on (from 0 to 1 as labeled on the power switch).
Step 5 Verify that the power supply is receiving AC power and outputting DC power by making sure that the INPUT and
OUTPUT power supply LEDs are lit and the FAULT LED is not lit or flashing. For an explanation of all the power
supply LEDs and the conditions that they indicate, see
When you first activate the power supply, you can verify the functionality of the LEDs by checking that each
Note
LED turns on for a couple of seconds.
If the Fault LED is flashing red, turn the power switch to standby (labeled as 0), check the power connections on the
power supply and the AC power source, and then turn the power switch back on (labeled as 1). The Input and Output
LEDs for the connected power supplies should be green and the Fault LED should be off.
Connecting DC Power Supplies with Power Sources
Connect each installed DC power supply with a DC power circuit as follows:
Note If you are using combined power mode (no power redundancy) or power supply (n+1) power mode,
connect all of the power supplies to the same power circuit (grid).
Before You Begin
• The power supplies are installed in the chassis.
• A DC power source is within reach of power cables that will be attached to the power supplies.
• Power cables are available to connect each DC power supply to the DC power source.
Step 1 Turn the power switch to standby (labeled 0 on the power switch).
Step 2
Turn off the power at the circuit breakers for the portions of the DC grid power that you are connecting to and verify
that all of the LEDs on the power supplies are off.
Before performing any of the following procedures, ensure that power is removed from the DC circuit.
Warning
Step 3 Size the power cables to the distance between the power supply and the DC power grid. If you need to cut the cable, cut
it at the end that connects to the DC power grid, remove 0.75 inch (19 mm) of insulation from the cut ends, and attach
them to the DC power system. Be sure to connect the negative cables to negative lines and positive cables to positive
lines.
For all your power connections, if you are using cables with two different colors, use one color cable for all
Note
positive circuits and the other color for all negative circuits.
Hazardous voltage or energy may be present on DC power terminals. Always replace the cover when the
Warning
terminals are not in service. Be sure uninsulated conductors are not accessible when cover is in place.
Cisco Nexus 7702 Hardware Installation Guide
70
Installing or Replacing Modules, Fan Trays, and Power Supplies
Power Supply LEDs