Hitachi EC702MP-BB3, Operation Manual

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E-Compact MP-BB3 Series
Stacking antennas
When using this system, the distance between them depends on the kinds of antenna used and the kind
of stacking used. This must be studied thoroughly in order to obtain the best solution for each case.
Cables and Connectors
All cables must be carefully installed in order not to be twisted during the installation process. When using
7/8" or 1/2" cables, please pay attention to their bending that must not be made in spaces smaller than
80cm. The cables can't force the connectors in the Input/Output of the equipment. The entry holes for the
cables in the shelter must be done in a way to avoid the water from entering them.
Follow the manufacturer's instructions when assembling them. All splices done outside the shelter must
be isolated with a special plastic tape and/or a plastic insulation material.
Avoid using silicon to coat the isolation made with auto-fusion tape. It has been verified that the silicon
chemical characteristics may provoke the drying of the auto-fusion tape.
3.4. Indoors Equipment Installation
Small equipment must be placed on a table in a way to provide easy access from all sides and be at
least one meter far from the walls.
Do not compromise the equipment’s air flow by placing objects on its top panel, which is its natural
ventilation.
The equipment must be placed directly on the shelter's floor as long as it is flat and they must be placed
at least one meter far from the walls to avoid obstruction of its ventilation system.
Some of these air outlet must be connected to the outside of the shelter through PVC tubing.
The AC cable has two terminations to be used exclusively in the equipment.
3.5. Equipment Grounding
Assemble the grounding separately from the power supply, with a rig and a grounding terminal that
comes with the equipment.
Normally, the retransmission sites are located in the highest spot of the chosen location, making them
more vulnerable to lightning strikes.
These discharges carry a great amount of electric energy, putting at risk not only the antenna and its
structure but also the equipment in the shelters. In order to minimize this effect and guarantee their
protection and continuous service during thunderstorms with lightning, the use of a reliable grounding
system is mandatory.
Lightning is a transient, high-current electric discharge that happens between the ground and the clouds.
Therefore, the most important part of a lightning protection system are the parts that are on the ground.
In order to maintain the low impedance of the technical grounding system, it must be carefully executed