IBM FlashSystem 5000 Series, Quick Installation Manual

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Connecting a DC power supply to a DC power source
An enclosure that is DC powered contains two DC power supply units (PSUs). Each unit must be
connected to a suitable -48V DC power source. To provide redundancy in a power circuit failure, connect
the two PSUs to different DC power sources.
Note: The connection to the DC power source must be made by trained service personnel. Ensure that the
connection is made in accordance with all the requirements of the equipment that is being used.
Use the supplied cables to connect the DC PSUs to the power sources. Use only the IBM supplied DC
power cable (IBM part number 00AR087) to connect the unit to a DC power source.
The supplied power must meet the input requirements that are listed in Table 20 on page 18.
Table 20. DC power supply input requirements
Requirement
Min Max
Voltage (V DC) -48 -60
Instantaneous (V DC for < 1 second) -36 -75
Inrush current at initial turn on (-48V DC) 34 A
Out of spec time before power off is signaled 5 ms
Important: Each PSU cable must be protected by a 20A circuit breaker. These instructions assume that
the circuit breaker is separate from the DC power distribution unit. Refer to the DC power distribution unit
documentation and the circuit breaker documentation for details. Follow the instructions that are given
there for connecting the circuit breaker to the power distribution unit and for connecting the DC power
cable to the circuit breaker.
One end of the cable ends in a plug that fits the DC PSU. At the other end of the cable, each individual wire
ends with a 6 mm diameter ring terminal that is designed to fit an M6 stud. Provide adequate strain relief
after you attach the ring terminals to the power source. Table 21 on page 18 lists the wire colors.
If it is necessary to replace the ring terminals with a different connector, choose a suitably sized and rated
UL-listed connector that is appropriate for the wire gauge and available current. Install the ring terminals
according to the instructions provided by the manufacturer.
Table 21. DC cable wire color coding
Color
Function
Blue Return
Green / Yellow Ground
Brown -48V
Securing the power cables
The DC power cable must be contained in a single rack and must not extend outside the rack to another
rack. The DC power cable is 4 m long. Connect it to the DC power source before you connect it to the PSU.
The PSU does not have a power switch. When power is connected, the outlets and the enclosure become
live. Review the information on securing the power cables to ensure that the cables are securely attached
to the enclosure.
18 IBM FlashSystem 5000 : FlashSystem 5000 Quick Installation Guide