Zebra Technologies Corporation MM4300-5800 Manuel D’Utilisation
Chapter 2: Infrastructure Device Installation
November 2007
2-10
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It is the responsibility of the Network Operator to ensure that the installation complies
with any local building codes and permits.
with any local building codes and permits.
Grounding Considerations
In order for a grounding system to be effective, a low impedance path to earth ground must be present.
The grounding system must have conductors of sufficient size to withstand the high fault currents that
must be shunted along this path. The lower the impedance the grounding system displays, the better its
capability to perform its task. The impedance requirement for a communications site is determined by
the classification of the site. Sites are broken down into 2 categories: Type A-Light Duty and Type B-
Light Industrial/Commercial. Type A-Light Duty sites have impedance requirements of 25 ohms or
less to ground whereas Type B- Light Industrial/Commercial sites have impedance requirements of
less than 5 ohms to ground. MOTOMESH networks fall into the Type B-Light Industrial/Commercial
category, and therefore must be treated with greater considerations as far as grounding requirements
are concerned.
The grounding system must have conductors of sufficient size to withstand the high fault currents that
must be shunted along this path. The lower the impedance the grounding system displays, the better its
capability to perform its task. The impedance requirement for a communications site is determined by
the classification of the site. Sites are broken down into 2 categories: Type A-Light Duty and Type B-
Light Industrial/Commercial. Type A-Light Duty sites have impedance requirements of 25 ohms or
less to ground whereas Type B- Light Industrial/Commercial sites have impedance requirements of
less than 5 ohms to ground. MOTOMESH networks fall into the Type B-Light Industrial/Commercial
category, and therefore must be treated with greater considerations as far as grounding requirements
are concerned.
Since Type B grounding requirements stipulate 5 ohms or less impedance to earth ground, things such
as soil pH, type of grounding rods, size of conductors, and ground enhancing materials must be taken
into account to achieve this goal. To verify the impedance requirements are met, a special
Earth/Ground Resistance Tester (megohmmeter) may be necessary.
as soil pH, type of grounding rods, size of conductors, and ground enhancing materials must be taken
into account to achieve this goal. To verify the impedance requirements are met, a special
Earth/Ground Resistance Tester (megohmmeter) may be necessary.
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If the MOTOMESH product is attached to a light arm and the attachment point meets
the Type B grounding requirements, then the grounding stud attachment point is not
required to be used.
the Type B grounding requirements, then the grounding stud attachment point is not
required to be used.
To avoid damage to the equipment, adequate grounding for all MOTOMESH
devices is mandatory.
devices is mandatory.
Assembling an AC Power MOTOMESH Duo Device
Use the following procedure to assemble a MOTOMESH Duo Device with AC power.
Procedure 2-3 Assembling a US AC Power MOTOMESH Duo Device
1
Place the brackets at the desired position on the pole.
2
Adjust the position of the box so that the antenna connecters are positioned vertically. Align the antennas
with the N-type connectors on the box and rotate to close.
with the N-type connectors on the box and rotate to close.
3
Insert the cable into the external Ethernet port and tighten the connector to ensure a weatherproof seal.
4
Insert the Power Plug into the 4-pin connector.
Note: For detailed wiring instructions, see the separate US Wiring instructions, generally provided with
the cable and power connector.
the cable and power connector.