Allied Telesis Removable Power Supply and Fan - Manual (Page 15)

Removable Power Supply and Fan
14
• AT-PWR01 DC is grounded at the GND terminal. In order to avoid
large circulating ground currents, the wires of each grounding cable
must be 18AWG or thicker.
• All grounding points are at the same ground level. That is, all power
connectors share a common power distribution unit.
Warning When mounting one or two AT-PWR01 DC PSUs to a grounded
rack, ensure that the ground level of the rack and the DC power connector
are the same.
Warning For x900-24 models, when using an AT-PWR01 AC power supply
and an AT-PWR01 DC power supply in the same switch, then the ground-
terminal of the DC power connector must be connected to the same
ground as the AC ground pin of the AC power connector.
If this is not possible, then you must ground the AT-PWR01 AC only, and
leave the AT-PWR01 DC power connector ungrounded. In this case, as a
safety precaution, ensure that the rack is also grounded.
Warning When SBx908 devices are connected with VCS stacking cables
(either HS-STK-CBL or XEM-STK-CBL), each individual stack member
chassis must be additionally grounded by using the rear grounding-terminal
on each device. In order to avoid large circulating ground currents, the wires
of each grounding cable must be 18AWG or thicker.
4. Connect the positive feed to the + (positive) terminal and the negative feed
to the - (negative) terminal. Tighten the terminals to between 2.4 and
4.0Nm (21.3 and 35.4 lbf in).
Note that the DC return input terminal must be connected as an Isolated
DC return (DC-I).
5. Ensure that there are no exposed cable strands.
6. Replace the cover. You must replace the transparent plastic terminal cover
before continuing.
7. Secure the supply cable to the rack framework or a similar object to ensure
that connections are isolated from any force applied to the cable.
8. Ensure that the circuit breaker for the supply circuit and the Run/Standby
switch on the PSU are off. Press and release the Run/Standby switch so that
it is not pushed in (which is the Off position).
9. Connect the supply cable wires to the circuit breaker.
10. Turn on the PSU by pushing in the Run/Standby switch.