Cisco NCS 4000 Series Hardware Installation page 212

Powering On the Chassis
Step 3 Set the power tray switch for Feed A to the ON (1) position. This powers on slots PWR MOD 0 through PWR
MOD 3.
Step 4 Verify that the Power Output LED on each power module in the tray is lit.
Step 5 Repeat Step 3 and Step 4 for Feed B.
Hardware Installation Guide for Cisco NCS 4000 Series
192
Installing Power Components