Install the P12V middle bus bar

Use this information to install the P12V middle bus bar.

Procedure

1. Align the P12V middle bus bars to slots on the P12V front bus bar. Then, slide the P12V middle bus bar into the slots to install it to the tray.
   1. Install the left-side bus bar.
   2. Install the right-side bus bar.
   Attention

   • Make sure to follow the bus bar installation sequence: Left-side bus bar > Right-side bus bar

   • Pay extra attention and care when moving the P12V middle bus bar. Make sure the bus bar does not hit the connectors on the GB200-NVL4 board.

     Figure 1. Prevent P12V middle bus bar hitting the connectors on GB200-NVL4 board
     
     

   Figure 2. Installing left-side P12V middle bus bar
   
   

   Figure 3. Installing right-side P12V middle bus bar
   
   
2. Install and fasten screws to secure the bus bar according to the table below.

   1a Install two (2x) PH1 screws, on right-side bus bar 2a Install one (1x) PH1 screws, on left-side bus bar Install the screws with a torque screwdriver set to 5.0 +/- 0.5 in-lbs, or 0.56 +/- 0.056 N-m.

   1b Fasten four (4x) T15 thumb screws, on right-side bus bar 2b Fasten four (4x) T15 thumb screws, on left-side bus bar First, install the screws with a torque screwdriver set to 1.5 in-lbs, or 0.169 N-m. Then, set the torque screwdriver to 17.5 in-lbs, or 1.977 N-m, and tighten the screws again.

   Figure 4. Installing screws on the P12V middle bus bars
   
   

   Figure 5. Installing screws on the right-side bus bar
   
   

   Figure 6. Installing screws on the left-side bus bar
   
   
3. With a torque screwdriver set to the proper torque, install the eight (8x) T30 screws to the P12V front bus bars.
   Note

   For reference, the torque required for the screws to be fully tightened/removed is 15.0 +/- 0.5 in-lbs, or 1.69 +/- 0.056 N-m.

   Figure 7. Installing P12V front bus bar screws
   
   
4. Connect cables to the GB200-NVL4 board, CX8 mezzanine board, and MCIO breakout board. See Internal cable routing.