Summit 550 W DC power supply units must
connect to a –48V source.
The DC power connection at your facility must be made by a qualified electrician,
following these instructions.
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Warning
Always make sure that the DC circuit is de-energized before connecting or disconnecting
the DC power cables on the DC power supply.
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Caution
Provide proper
connection and strain relief on the DC power cables in accordance with all local and
national electrical codes.
- Verify that the DC circuit
is de-energized.
- Attach an
ESD-preventive wrist strap to your bare wrist and connect the metal end to an
appropriate ground point on the rack.
- Slide the cover off the
terminal block.
- On each terminal, loosen the screw
enough to allow the spade terminal to slide underneath the captive square washer.
-
Connect the DC power
input cables as follows:
-
Slide the spade terminal
of the negative
wire (–48 V) under the captive square washer on the negative terminal
(labeled –).
Connecting the
Negative Power Wire to a –48V Source (550 W DC Power Source)
-
Slide the spade terminal
of the positive
wire (–48 V RTN) under the captive square washer on the positive terminal
(labeled +).
Connecting the
Positive Power Wire to a –48V Source (550 W DC Power Source)
-
Tighten both screws on the terminal block to 7
in‑lb (0.79 N m).
-
Snap the cover into place over the terminal
block.
- Connect the cables to the
DC source voltage, using hardware appropriate to the installation site and following
local and national electrical codes.
- Energize the DC circuit.
Leave the ESD strap permanently connected to the
rack, so that the strap is always available when you need to handle ESD-sensitive
components.
You can now connect network interface cables to the switch, using
the instructions in Connect Network Interface Cables.