CSLB C-46 Solar ContractorElectrical and Plumbing CodesMedium
A solar contractor is installing a battery energy storage system (BESS) as part of a hybrid PV installation in a commercial building. According to the National Electrical Code (NEC), what is the minimum required working clearance in front of the BESS if it contains uninsulated live parts that require examination, adjustment, servicing, or maintenance while energized?
- A36 inches
- B48 inches
- C30 inches
- D24 inches
Show answer & explanationAnswer & explanation
Correct answer: A. 36 inches
NEC 110.26(A)(1) specifies a minimum working clearance of 36 inches (3 feet) in the direction of access to live parts operating at 600V, nominal, or less, for equipment that requires examination, adjustment, servicing, or maintenance while energized.
Why the other options are wrong
- B. 48 inches is a common clearance for higher voltages or specific conditions, but not the minimum for this general scenario.
- C. 30 inches is the minimum width of the working space, but not the depth.
- D. 24 inches is insufficient for the specified conditions.
NEC BESS Working Clearance
The minimum unobstructed space required by the National Electrical Code (NEC 110.26) in front of a Battery Energy Storage System (BESS) or other electrical equipment containing live parts for safe access, examination, and maintenance.
- Applies to equipment requiring access while energized.
- Ensures worker safety.
- Minimum depth is 36 inches for most common voltages.
Memory trick: Give live parts three feet of freedom to work safely.