Zhone MXK, Руководство по установке оборудования

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Install the MXK
42
MXK Hardware Installation Guide
•
Use the ground bus of a dedicated AC service panel as the location/site
ground of the MXK equipment. This ground bus must already be
connected to the main service panel ground or main building ground
reference.
•
The impedance of the link between the ground terminal of the MXK and
the location/site ground to which it is connected must be less than 0.25
ohms.
•
The rack the MXK is installed in must be properly grounded.
•
Never connect a single-point-ground conductor from the MXK to
structural steel members or electrical conduits. Specifically, never tie this
conductor to a ground source or grounded electrode that is not hard-wired
to the building ground reference conductor.
•
It is recommended to avoid running in-building cabling near fluorescent
lights and other sources of high frequency radiation such as transformers.
•
Avoid spliced conductors. Use continuous conductors, which have lower
impedance and are more reliable than spliced ones.
•
Terminate all conductors in a permanent manner. Ensure all terminations
are easily visible and accessible for maintenance purposes.
•
Tag ground connections clearly with a message such as “CRITICAL
CONNECTION: DO NOT REMOVE OR DISCONNECT.”
•
Although some electrical codes permit the use of a conduit as the sole
ground conductor between equipment, it is still recommended to use a
separate insulated ground conductor through the same conduit. The
separate insulated ground conductor maintains the safety ground
connection if the conduit is corroded or disconnected.
•
Avoid a ground path via serial craft interface RS-232C. The MXK
RS-232C local craft interface has pins referenced to ground. To prevent
undesirable ground path via an attached computer, it is recommended that
you only use a portable computer. If only a desktop computer or VT-100
type monitoring equipment is available, use it in conjunction with a UL/
CSA Certified RS-232 Opto-Isolator.
Ground conductors for the MXK must meet the following requirements:
•
No smaller than 10 AWG at any point.
•
Does not carry current under normal operating conditions.
•
Must be tied to the +48V battery return at the main power Distribution
Center
•
Should be hard wired to the main ground reference.
Connect power to the front of the MXK and ground
the chassis
Power on the MXK 819 is located at the front of the chassis, see Figure 15 .