ESC Electrical Grounding & Bonding Flashcards
6 cards from real ESC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 ESC Electrical Grounding & Bonding flashcards as text
What is the primary purpose of electrical grounding in a system?
Answer: To provide a safe path for fault current to return to the source
Grounding provides a low-impedance path for fault current to return to the source, enabling overcurrent devices to operate and clear the fault.
Which NEC article primarily covers grounding and bonding requirements?
Answer: Article 250
NEC Article 250 covers all requirements for grounding and bonding of electrical systems and equipment.
What is the primary function of bonding in an electrical system?
Answer: To establish electrical continuity between conductive parts
Bonding establishes electrical continuity between conductive components to ensure they are at the same potential and can carry fault current.
What is a grounding electrode conductor (GEC)?
Answer: The conductor connecting the grounding electrode system to the service equipment
The GEC connects the grounding electrode system to the service equipment neutral or grounded conductor.
If a single ground rod does not meet the 25-ohm resistance requirement, what does the NEC require?
Answer: Install a supplemental grounding electrode
Per NEC 250.56, if a single ground rod measures more than 25 ohms to ground, a supplemental electrode must be added.
Which grounding electrode is generally considered the most effective per NEC requirements?
Answer: Concrete-encased electrode (Ufer ground)
The concrete-encased electrode (Ufer ground) is highly effective due to its large surface area in contact with the earth and is required to be used when available.