Figure 3-1. Grounding in Lower Frequency Equipment
The wire tables show that No. 13 AWG wire has a cross-sectional area of 5,178 circular mils and could be used.
However, No. 12 AWG is more commonly available and would probably be used instead.
Where an insulated ground wire penetrates a metal sheet such as the equipment case, adequate
physical protection must be provided with grommets, plastic sleeves, or other protectors to ensure continuous
isolation between the floating chassis and the equipment case or cabinet.
22.214.171.124.3 Color Code. To aid in distinguishing the signal ground terminal from other terminals on the
equipment, it should be clearly marked with a permanent yellow label or color code.
126.96.36.199.4 Cabinet Bus Bar.
Each rack or cabinet containing two or more separate pieces of lower frequency equipment should
have a bus ground installed that is insulated from the rack or cabinet.