1. System Installation Requirements
1-19
TI 33Q01J10-01E
1.4
Grounding
To avoid shock hazards and minimize the effects of external noise, the installed devices
must be grounded with a ground resistance of 100 ohms or less and a grounding bus
of 22 mm
2
or thicker. Do not ground the CS 3000 system to the same ground as devices
of other systems. In the CS 3000 field control station (FCS), expansion I/O cabinets, and
console type human interface station (console type HIS), grounding bars are provided.
When the power supply is plug-in rather than hard-wired, use the power cable for
grounding.
The reference-grounding bar and the concatenation grounding bus, which is for potential
equalization defined with the relevant standards, or grounding including meshed earth
described in IEC 60364, IEC 62305 and IEC 61000-5-2 can be selected to satisfy the
specification of 100 ohms or less.
The term “independent grounding” means to avoid any impedance caused by grounding
the system to the same ground as devices of other systems, and it does not necessarily
forbid equipotential bonding, nor require to install a grounding electrode independently.
May 18, 2007-00
