Providing Power to the DSC 8000

Providing power to the DSC 8000 varies depending on the site and national and/or local safety codes and practices.

Power is routed from the building’s -48 VDC supply source to the PDU high power input terminals. This power is then distributed from the PDU high power outputs to the DSC 8000 shelves (see the following figure).

DSC 8000 Power Connection Diagram

Before you start any of the procedures in the section, make sure that the DSC 8000 is properly grounded (refer to Grounding the DSC 8000).

For more information about power management, refer to Power Management. For information about power requirements, see Verifying Power Requirements.

The DSC 8000 must be connected to properly rated power sources. For permanently connected equipment, a readily accessible disconnect device should be incorporated in the building wiring installation. Circuit breakers should be rated to handle the current indicated in the input specifications listed on the product identification label on the rear of the DSC 8000 shelf.

It is recommended that you review and thoroughly understand the information contained in this section before installing any power connection.

Connect Facility Power to the PDU

The maximum power consumption for the DSC 8000 platform is 2,200 W per shelf. Depending on your configuration, each shelf in a multi-shelf configuration consumes different levels of power, up to the maximum power capacity limit of 2,200 W.

Power is routed from the building’s -48 VDC supply source to the PDU high power input terminals. The power then is then distributed from the PDU high power outputs to the platform shelves.

The following table describes the required Power Distribution Unit (PDU) power connection hardware.

Connect the PDU to Facility Power

Start

1. If the power service panel cover is attached to the back of the PDU, use a Phillips head screwdriver to loosen the two retaining screws holding it in place.

   
     

2. Position the power service panel cover so the screw heads align with the wide part of the keyhole cutouts in the cover.

3. Remove the power service panel cover to reveal the PDU power terminals.

4. There are two sets of power inputs, A and B. Each power input block contains two inputs, labeled “Battery,” and two return terminals, labeled “Return.”

   

   
   Power input block B, on the left, has its battery inputs on the left and its returns on the right, while power input block A on the right has its returns on the left and its battery inputs on the right.

    
     

5. Using an appropriate wire cutting tool, cut two 4 AWG cables no longer than 15.2 m (50 ft.) with red insulation for the PDU battery (-48VDC) power input blocks.

6. Using an appropriate wire cutting tool, cut two 4 AWG cables no longer than 15.2 m (50 ft.) with black insulation for the PDU return power input blocks.

7. Remove approximately 12.7 mm (0.5 in.) of the insulation on both ends of each cable.

   Warning

   An exposed wire lead from the DC input power source can conduct harmful levels of electricity. Make sure that no exposed portion of the DC input power source wire extends from the ring terminal.

              

8. Insert one end of a cable into a 6.86 mm (1/4 in.) double ring lug connector such as the Panduit LCDX4-14B-L, or equivalent, and using the appropriate crimping tool for this terminal, crimp the terminal onto the wire.

9. Repeat for each end of all four cables.

10. Remove the nuts and lock washers from the two return posts on the PDU power input block A.

11. Place a double-hole ring terminal attached to one of the black cables on the two return posts.

    Tip

    The closest metric equivalent for a 1/4 in. ring terminal is a ring terminal for an M6 stud. This ring terminal has a 6.86 mm hole.

                    

12. Thread a lock washer and nut onto each return post. The nuts and lock washers on the posts are 7/16 in. Use the appropriate torque wrench to securely fasten these nuts and lock washers onto the posts using 5.0Nm (45 lbf-in) torque.

13. Feed the cable to the appropriate fuse panel or breaker switch from which the shelf DC power is supplied and attach to the return conductor according to the appropriate electrical code.

14. Remove the nuts and lock washers from the two posts on the PDU power input block A marked “Battery”.

15. Place a double-hole ring terminal attached to a red 4 AWG cable on the two battery posts.

     
      

16. Thread a lock washer and nut onto each battery post. The nuts and lock washers on the posts are 7/16 in. Use the appropriate torque wrench to securely fasten these nuts and lock washers onto the posts using 5.0Nm (45 lbf-in) torque.

17. Feed the cable to the appropriate fuse panel or breaker switch from which the shelf DC power is supplied and connect according to the appropriate electrical code.

18. Repeat steps 10-17 for the return and battery posts on the PDU power input block B.

    

     
    

19. Locate the power service panel cover and position it so the screw heads align with the wide part of the keyhole cutouts in the cover.

20. Push the screw heads through the wide part of the keyhole cutouts in the cover and reposition the cover so the screw heads align with the narrow part of the keyhole cutouts.

21. Using a Phillips head screwdriver, tighten the two retaining screws until they securely hold the power service panel cover in place.

22. Label all cables for future identification as required.

Connect Power to the Shelves

The maximum power consumption for the DSC 8000 platform is 2200W per shelf. Depending on your configuration, each shelf in a multi-shelf configuration consumes different levels of power, up to the maximum power capacity limit of 2200W.

Power is routed from the building’s -48 VDC facility supply to the PDU power input terminals. The power is then distributed from the PDU high power outputs to the shelves.

Before performing any task in the following procedure, make sure that the -48 VDC power source that you are connecting the shelves to is turned OFF. Ensure there is a tag or label over the power source switches or breakers (lock-out/tag-out) to indicate that the power source is turned OFF intentionally.

The following figure shows the DC Power Entry Module (PEM) grounding and power connections.

DSC 8000 Direct Current PEM Connections

Connect the Shelf to the Power Distribution Unit (PDU)

Start

1. Ensure that the DSC 8000 is properly grounded (refer to Verifying Ground Requirements).
2. Verify that the DC input power source is de-energized.

3. Remove the protective power input cover to expose the DC power input panel on the PEM. Grasp the cover with your thumb and index finger, then flex the cover to either side and lift the opposite side.

   
    

4. Starting at the Power Distribution Unit, connect the cable from the A Return on the PDU to the RTN A (Return) connection on the PEM (see Figure DSC 8000 Power Connection Diagram). The PDU and PEM cable connections are labeled as shown below.

   

   
     

5. Starting at the Power Distribution Unit, connect the cable from the A Battery on the PDU to the -48 A connection on the PEM (see Figure DSC 8000 Power Connection Diagram).
6. Torque the terminal nuts [11mm (7/16 in.)] to 3.4-4.0Nm (30-35 lbf-in.).

7. Repeat steps 4 through 6 to connect the -48 DC power to the “B” Terminal and its Return.

   Tip

   There are four cables to be connected on each PEM (shelf).

            

8. When all cables have been connected to the PEM, snap the plastic power input panel cover in place.

   
     

9. Repeat steps 4 through 8 for each shelf.

Power Up the Platform

When you have provided the appropriate power input and grounds to the DSC 8000 platform (refer to Grounding the DSC 8000 and Figure DSC 8000 Power Connection Diagram), the power modules in each shelf are automatically enabled.

The system is properly powered when the PM In Service LEDs display steady green. The PM LEDs show the power input status for each module. The LED of a redundant PM displays a steady amber (see the following figure).

Power Module (PM) LEDs

If the PM LEDs display red, do the following:

• Check that all power feeds are properly connected and that the breakers are not tripped.
• Check that all power feeds are working. If there is a power feed that does not work, the LEDs to all the even (2 and 4) or odd (1 and 3) numbered power modules on a shelf are off.
• Check the power modules. If a single LED displays red that PM is faulty.

Start

1. Make sure that the DSC 8000 shelf is properly grounded (refer to Grounding the DSC 8000) and all power connections are properly installed.
2. Turn on the -48 VDC power source to which the platform is connected.
3. If the PM LEDs are red, do the following:
   
   1. Check that all power feeds are properly connected and that the breakers are not tripped.
   2. Check that all power feeds are working. If there is a power feed that does not work, the LEDs to all the even (2 and 4) or odd (1 and 3) numbered power supplies on a shelf are off.
   3. Check the power modules. If a single LED displays red, that PM is faulty.
4. If the shelf power is connected as expected, remove the tag or label over the power source switches of breakers (lock-out/tag-out) that indicated the power source was turned OFF intentionally.

Connect the PDU Alarm Relay Contacts to an External Monitoring System

Start

1. At the rear of the panel, pull to extend plastic reference card below alarm terminals. (See figure below.) With PWR ON A lit (normal operation)—but with PWR ON B LED off (failure operation)—test power-fail relay and contacts at PWR ALM terminals on the rear of the panel:
   • Expect an open circuit (∞Ω) between Terminals C and NC.
   • Expect continuity (0Ω) between Terminals C and NO.
     
     
     
     
2. Test the fuse alarm relay contacts at the FUSE ALARM terminals on the rear of the panel. For both the VIS (visual) and AUD (audible) indicator contacts,
   • Expect continuity (0Ω) between Terminals C and NC.
   • Expect an open circuit (∞Ω) between Terminals C and NO.
     
3. Repeat Steps 1 and 2 to power up Side B. PWR ON A and PWR ON B must both be lit.
   
4. With PWR ON A and B lit (normal operation), test power-fail relay and contacts at PWR ALM terminals on the rear of the panel:
   • Expect continuity (0Ω) between Terminals C and NC.
   • Expect an open circuit (∞Ω) between Terminals C and NO.