Attach a ground wire from one of the threaded studs (A) at the bottom of the housing, to the mounting plate (B). The ground resistance between all system parts shall be <. e G” function of ABB SACE low voltage circuit-breakers. With this function it is possible to ensure protection against: − earth faults downstream the circuit-breaker on the secon-dary side of the Medium/Low voltage (MV/LV) transformer (unrestricted earth faults or downstream earth faults); − earth. Figure 1: 3-wire 120/240-V AC single-phase secondary distribution system (From 1987 NEC, Fig. Figure. Primary distribution systems consist of feeders that deliver power from distribution substations to distribution transformers. Each DISTRIBUTION BOX and controller must be grounded. Understanding grounding and bonding for industrial control systems is no simple task.
