In Scenario 230.26, what is the panelboard configuration?

• A. 120/208-V, 3-ph, 4-W panelboard
• B. 120/240-V, 3-ph, 4-W panelboard
• C. 120/208-V, 1-ph, 4-W panelboard
• D. 120/240-V, 1-ph, 4-W panelboard

Answer: (A)

Panelboard selection is driven by the service feeding it. In many commercial buildings, a 3-phase four-wire system used is a 120/208 V configuration. That means the panelboard is a 120/208-V, 3-phase, 4-wire unit. In this setup, the voltage between any two hot legs is 208 V, while the voltage from any hot leg to neutral is 120 V. The neutral allows standard 120-V loads, and the 208-V line-to-line voltage serves 3-phase equipment. This matches the Scenario 230.26 description and explains why 120/208-V, 3-ph, 4-wire is the correct panelboard configuration. The other options describe less typical or single-phase configurations and don’t fit a standard 3-phase four-wire service.