Iwatsu ADIX VS, Техническое руководство

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Chapter 4 – System Location and Environment
19
Grounding the ADIX-VS
Example 1. Using the AC Power Cord Ground Conductor
Once it has been determined and verified that the electrical outlet that the system is connected to is a
dedicated and isolated telecommunications earth ground, as defined by the National Electrical Code
and the TIA / EIA as stated above, the electrical power cord ground conductor can be used as the
system’s reference to earth ground potential.
This means that the ground receptacle of the outlet is connected directly to a dedicated ground
conductor that is secured to an effective earth ground of known potential. This is defined in detail
the Articles above.
If the origin or quality of the electrical outlet ground is suspect, or is known not to have been wired
in accordance with the National Electrical Code and the TIA / EIA as stated above, the AC Power
Cord Ground is to be considered a poor ground. In that case, an external ground conductor must be
used as the effective ground reference as defined below.
The ground conductor of the AC Power Cord is to be secured on the bottom of the Control Module
frame as illustrated in Figure 3.
Example 2. Use of an External Ground Conductor
An external ground conductor must be used as the system’s reference to an effective earth ground if
it has been determined that the AC Power Outlet Ground is ineffective or is not a dedicated
telecommunications quality ground as defined by National Electrical Code and the TIA / EIA.
The ground conductor is to be secured on the bottom of the VS-KSU Control Module frame as
illustrated in Figure 3. The opposite end of the ground conductor must be bonded to an effective
earth ground potential as illustrated in Figure 3. The conductor must be bonded to an earth ground
rod of a known potential.
The use of cold water pipes that have historically been used for ground reference should be avoided.
The prevalent use of PVC pipe in most construction today renders this ground source unreliable. It
should also be noted that the use of a copper water pipe is prohibited by many building codes.
The grounding conductors must be a minimum of 12 AWG. Use wire that is either green or green
and yellow striped. Use crimp terminals for all stranded wire.
Figure 3 illustrates the proper ground termination points for ground straps between the VS-KSU
Control Module and the earth ground conductor.