In our previous issue, we showed that Art. 516 is not as complex as it appears. Essentially, you choose from three options. After you make your choice, however, you have three additional possibilities to consider. Sections 516.3(D), (E), and (F) tell you to do the following:

  1. If equipment is within a Class I location, then apply the requirements of 516.4.
  2. If equipment is not within a Class I location (or a Class II), then apply the requirements of apply 516.5.
  3. Read through 516.10 to see if any of the equipment you’re working with is considered "special equipment."

One last note on Art. 516: It has some terminology misuse in 516.10(6) and 516.16. These refer to "grounding." However, grounding the items mentioned in these requirements serves no purpose from a technical point of view. So what did the Code Making Panel (CMP) mean when they wrote this?

To answer that, we merely need to read the definitions of grounding and bonding in Art. 100 and then read the actual requirements of 516.10(6) and 516.16. The CMP meant bonding (metallic path), not grounding (connecting to earth). Make these installations conform to Art. 250, Part IV.