ABB AC 800M, Аппаратное обеспечение и эксплуатация

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Power Supply Section 2 Installation
46 3BSE 027 941 R301
Type of Field Cable
Always use shielded cables for the following applications:
• Communications
• High-frequency pulse transmission
• Low level analog signals, for example Pt100 and thermocouples
• Analog applications with a system accuracy of 12 bits or more.
Unshielded cables may be used for other applications. The signal and return
conductor must always be located in the same cable.
Lightning Protection
Industrial installations and power plants are normally provided with well-integrated
grounding networks, installed as part of the power distribution system. Such
installations do not require additional lightning protection unless using overhead
wiring or suspended cables in an outdoor environment.
However, large dispersed plants such as water supply installations and oil refineries
will have an inadequate grounding system where signal cables may be routed above
ground. In such cases lightning protection equipment must be installed.
Should cables be discovered outside the grounding system (even at a short distance
such as 10 m [9.1 yds]) lightning protection equipment must be installed.
Power Supply
Under normal circumstances, the power supply required by AC 800M Controller
and associated field equipment can be obtained from the plant’s standard 120/230
V AC mains supply.
Mains Net Filter
It is not necessary to use mains net filters when using the SD821/822/823 power
supply units.