IBM DS4700 manual DC power source

4.Complete the wiring from the disconnect device to the terminal marked -48V of the Reliably grounded safety extra low voltage (SELV) dc power source. Connect the POS RTN and ground lines of the dc power cable to the terminals marked POS RTN and GND on the dc power source, as shown in Figure 95. For maximum protection against power loss, connect each of the two dc power supplies to a different power source.

5

1 2 3 4

Figure 95. DC wiring from DS4700 Express to disconnect device and dc power source

Table 39. DC power source wiring descriptions

Number	Description
1	Pin 1: -48 V dc
2	Pin 2: POS RTN
3	Pin 3: GND
4	DC power source
5	Disconnect device

5.Continue with “Powering on the storage subsystem” on page 119 for the initial startup of the storage subsystem.

Chapter 3. Cabling the storage subsystem 115