Chapter B Using DC Power 95
Caution – Ensure that you do not turn on power to the array module or the
connected drive modules until this guide instructs you to do so. For the proper
procedure for turning on the power,see ““Connecting Power Cables” on page 94.”
Caution – Electrical grounding hazard – This equipment is designed to permit the
connection of the D.C. supply circuit to the earthing conductor at the equipment.
▼Connecting the Cables
1. Disconnect the two-pole 20-amp DC circuit breaker for the storage array.
2. Ensure that all DC power switches on the DC-powered array module and all
DC power switches on any connected, DC-powered drive modules are turned
off.
3. Connect the DC power connector cable to the DC power connector on the back
of the array module.
Caution – The three source wires on the DC power connector cable (–48 VDC)
connect the array module to centralized DC power plant equipment, typically
through a bus bar located above the cabinet.
4. A qualified service person is required to make the DC power connection per
NEC and CEC guidelines. A two-pole 20-amp circuit breaker is required
between the DC power source and DC-powered modules for over-current and
short-circuit protection. Connect the DC power source wires on the other end
of the DC power connector cable to the centralized DC power plant equipment
as follows (see “DC Power Connector Cable and Source Wires”on page 92).
a. Connect the brown –48-VDC supply wire to the negative terminal.
b. Connect the blue return wire to the positive terminal.
c. Connect the green/yellow ground wire to the ground terminal.
5. If applicable, connect a DC power cable to each DC-powered expansion tray in
the storage array.