Master Electrician Exam (NEC)Grounding and BondingMedium
A master electrician is installing a new panelboard in an existing commercial building. The panelboard is fed by a feeder from the main service panel. The raceway consists of EMT. Which of the following statements is true regarding the use of the EMT as an equipment grounding conductor (EGC) for this feeder circuit?
- AEMT is permitted as an EGC only for circuits operating at 120V or less.
- BEMT is permitted as an EGC if the fittings are listed for grounding and installed correctly.
- CEMT is never permitted to be used as an EGC.
- DEMT is permitted as an EGC only if it is liquidtight flexible metal conduit.
Show answer & explanationAnswer & explanation
Correct answer: B. EMT is permitted as an EGC if the fittings are listed for grounding and installed correctly.
NEC 250.118 lists acceptable types of equipment grounding conductors. EMT is specifically listed in 250.118(4) as an acceptable EGC when installed in accordance with Chapter 3, and all fittings and connections are made up tight. This means the fittings must be listed for grounding and properly installed to ensure electrical continuity.
Why the other options are wrong
- A. The voltage rating of the circuit does not restrict EMT's use as an EGC, as long as it meets other installation requirements.
- C. This is incorrect; EMT is a commonly used and permitted EGC.
- D. Liquidtight flexible metal conduit is a different type of raceway and has its own rules; it does not dictate EMT usage.
EMT as Equipment Grounding Conductor
Electrical Metallic Tubing (EMT) is recognized by the NEC as an acceptable equipment grounding conductor when properly installed with listed fittings that ensure electrical continuity.
- Permitted by NEC 250.118(4).
- Requires listed fittings and proper installation.
- Provides a low-impedance path for fault currents.
Memory trick: EGCs: wire, conduit, or cable armor.