Acom 06AT User Manual page 67

User's Manual | ACOM 06AT | Automatic Antenna Tuner and Switch
8) All cables entering the building should only be laid out in one zone, low in building foundation,
and the cable braids and grounding terminals of their pulse overvoltage limiters (surge
arrestors) should be grounded immediately after coming out from underground, in a common
point called the main grounding plate of the building, to which are connected the mains
neutral, (this would not be permitted in the UK) and the structural metal elements of the
building – concrete reinforcement, metal pipe installations, metal frames, electrical panels,
and other electrically conductive elements of the building (dangers with much plastic tubing
in use in domestic water and central heating pipe systems).
The main grounding plate of the building should in turn be equipped with a special individual low-impedance
grounding system, driven or buried directly in the ground, deep enough under the expected frost level of soil
in your area, and in compliance with all requirements of the local standards and regulations for electric safety,
fire safety and lightning protection.
The expected frost level of soil in your area can be obtained from the local electricity company or weather
service. This is very important, since when soil freezes, its resistance dramatically increases. While the frost
level of soil is not normally critical in the case of buried counterpoises of RF antennas, an insufficient depth
of driving or burying in the ground could increase the resistance of the protective grounding system to exceed
the standard requirements several times, i.e., you may be often left without electrical and lightning
protection in the winter.
9) All objects located in the room of the radio station should be grounded to a common point
called the main grounding plate of the radio station, which in turn should be connected
through a low-impedance connection to the main grounding plate of the building (see Point
above).
10) The grounding terminals of all equipment in the room, the shields of all cables coming in and
going out of the room (including telephone, telegraph, network, video, Internet, TV, etc.), as
well as the grounding terminals of all pulse overvoltage limiters (surge arrestors), that normally
supply any of the wires of these cables, should be connected to the main grounding plate of
the radio station.
October 2022 S e c t i o n APPENDIX 1 | Lightning Protection | Page 67 of 70
8)