ECI XDM-300, Руководство по установке и обслуживанию

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Before You Start XDM-300 Installation and
Maintenance Manual
2-22 ECI Telecom Ltd. Proprietary 417006-2311-0H3-A00
To check for proper grounding wiring:
1. Measure and record the output voltage of the power supply at the power
supply terminals. Make sure that it is within the specified limits (XDM
equipment can use -75 VDC to -40 VDC).
2. At the RAP: Measure and record the voltage between the positive (red) lead
of the power source and the RAP metallic body. The voltage difference
must not exceed 5 V.
3. At the RAP: Measure and record the voltage between the negative (black)
lead of the power source and the RAP metallic body. The voltage
difference must not exceed the supply voltage measured in Step 1, and must
be within 5 V of the measured voltage.
For example, if the power supply voltage is -48 VDC, the voltage measured
in this step cannot be more negative than -48 VDC, nor more positive than
-43 VDC.
Rack grounding requirements
Connect the rack to the site grounding bar with a ground cable according to
ETSI recommendations (top/bottom connection).
The rack is supplied with a main copper or brass grounding bolt welded to the
rack frame. The grounding stud is identified on the rack by the ground symbol
label.
The rack grounding bolt must be connected to the site grounding bar by a
35 mm
2
(2 AWG) grounding cable or thicker, as short as possible, complying
with UL/ETSI recommendations. The bolt must be free of paint. The cable
should be made of copper strands, and terminated on both sides with bolt
terminals.
N
OTE
:
If necessary, the gauge of the grounding lead can also
be reduced to the gauge of the RAP power leads.
The rack mounting rails must be free of paint, and provide electrical continuity
to the main grounding bolt. The resistance between any rail and the rack main
grounding bolt must be less than 0.1
Ω
.
Pay particular attention to the area in which the RAP is attached; remove paint
from the rack in this area to ensure efficient electrical contact.