Grounding

Module from the Electrical Engineering Curriculum curriculum.

Module 7 - Grounding and Bonding · Learning Objectives · 1. Apply IEEE Std 142 Green Book for plant grounding system · 2. Design grid for 1 ohm or less resistance to earth · 3. Select solidly grounded, high-resistance grounded (HRG), or ungrounded · 4. Size neutral grounding resistor (NGR) per IEEE 142 for <10 A ground fault · 5. Apply static bonding for tank loading and high-flow transfers · System Grounding Methods

Method	Ground Fault Current	Pros	Cons	Typical Use	Notes
Solidly grounded	Full fault current	Simple, lowest cost	Arc-flash high, trip on fault	LV (<600V) systems	Most common
Low-resistance grounded	200-1000A	Limit damage	Still trips fault	MV industrial	Heavy pumping stations
High-resistance grounded	<10A	Run on first fault, alarm	Needs detection scheme	4.16kV continuous process	Most refineries MV
Resonant (Peterson coil)	Very low	Self-extinguish arcs	Complex tuning	Rare	Long overhead lines
Ungrounded	Capacitive only (few A)	Run on fault	Transient overvoltage risk	Legacy only	Avoid

Source: Electrical_Engineering_Curriculum_v1.xlsx · Sheet: Grounding

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