Hitachi S10VE, Руководство пользователя

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6. Installation
6-3
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Why is grounding necessary?
- The failure of a transformer or other device might cause high voltage power to travel from a high-voltage
device to a low-voltage device. In this situation, a ground connection prevents harm to the operator by electric
shock.
- Electromagnetic shielding is used to prevent malfunction of the internal circuits and communication lines of
the equipment due to external electromagnetic noise. However, this shielding has no effect unless the shield
and cabinet are both grounded.
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Regions prone to lightning
High-frequency noise and surge voltage can damage the PCs or cause it to malfunction. In regions prone to
lightning, take measures to arrest surge voltage. These might include lightning rods and insulating transformers
(electrostatically shielded).
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Cold and hot regions
Operation of the PCs is not guaranteed in environments that are outside the specifications. In particularly cold
and hot regions, the temperature or relative humidity of the building or room where the PCs are installed might
exceed or fall below the environment specification. In this case, use an air conditioner or heater to adjust the
temperature.
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Wiring using ducts and conduits
If a signal cable of the PCs runs in parallel with the AC cable of another device, use a duct, conduit, or other
means to keep the cables separate.
You must ground ducts and conduits without fail.
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Measures against rats
The key to keeping rats out of the equipment and stopping them from damaging the cables is to eliminate any
environments that are hospitable to rats. Specifically, you must curtail their ability to move about, and not leave
any food in the area.
Take care when using professional services to eliminate rats. Certain rat repellents can cause problems with the
connectors.