/ Field knowledge · NEC 100 · Sparky Edition

“It has a ground” is not a connection spec.

NEC Article 100: “it has a ground” is not an equipment-connection specification. A three-phase motor may not need a neutral. The packaged controls might. The EGC is not the intended normal load-current return.

Educational 2026 NEC Article 100 terminology. Confirm the adopted edition. This is not a bonding location, conductor size, or field correction detail. Distinct from grounding vs bonding.

The complete equipment wiring diagram settles whether a replacement RTU, pump, or control panel needs a neutral — not a guess from the largest motor. A visible color is an observation, not proof of function. An EGC need not always be a separate wire; permitted wiring methods depend on adopted rules. Qualified verification establishes the complete permitted path, not a count of green wires.

Add a neutral at a convenient enclosure

Do not add a neutral-to-equipment connection downstream to “make a ground.” Improper connections can put normal current on metal paths. Write the uncertainty precisely: equipment control-power neutral requirement not reconciled with the approved wiring diagram; electrical designer and vendor to resolve before feeder release. “Check grounding” is not actionable.

Source: Sparky neutral/EGC · tool: neutral screen · voltage: 208Y/120.

What to send

The package wiring diagram / nameplate and the feeder schedule (safe photos only).

If the RTU swap “already has a ground”

Send the wiring diagram. Masterbuild will say whether Article 100 even has a neutral on that package — or the EGC was used as a substitute.

Send Project Background

+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com

Masterbuild provides engineering services under a written scope. Nothing on this page is project-specific engineering advice, a code interpretation for your project, or a representation about permit approval. Sparky Edition uses the 2026 NEC as model-code education. Confirm the adopted edition. Field observations do not establish electrical safety; only qualified personnel using required safe-work procedures should access electrical equipment. This page does not size conductors or pick bonding locations.