A neutral-ground bond is the connection between the neutral conductor and the grounding system. It should only be made at the main service entrance panel. The neutral carries current. If it is bonded to ground anywhere else, such as in a subpanel, return current gets parallel paths back to the source through the ground system. How much current flows on those stray paths depends on the imbalance between the two lines and on the resistance of each path. Current on the ground system can energize equipment enclosures, metal piping and even the ground underfoot. This can cause electrocution, equipment damage or serious injury. Equipment differs: some backup interface versions must not have the bonding jumper installed, while service-entrance-rated versions include neutral-ground bonding that depends on the AC installation. Some string inverters warn against fitting a neutral-to-ground jumper when the neutral conductor is connected, because this can damage the unit and void the warranty. Always follow local code requirements and check with the authority having jurisdiction or a master electrician before adding or removing a bond. Bond points can be checked with continuity or bond-resistance tests, which look for a low-resistance connection.
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explainsc1 drafted · lead Electric shock
A neutral-ground bond made anywhere other than the service entrance can put return current onto grounded parts such as enclosures, pipes and the ground itself, which creates a risk of electrocution.
sec=h8 h=b1b83d29d236sec=h6 h=c778f65a11ebrelated_toc2 drafted · lead SolarEdge Backup Interface proposed
The jumper should not be installed on the BI-NU version. On the BI-EU version, which is service-entrance certified and includes neutral-ground bonding, it depends on the AC installation.
sec=h8 h=b1b83d29d236sec=h24 h=f77798657429c3 drafted · lead Partial-home backup
When loads are moved to a backup subpanel, neutral and ground must not be bonded at that subpanel.
sec=h6 h=c778f65a11ebc4 drafted · lead Authority having jurisdiction
Bonding must follow jurisdictional rules. Consult the AHJ when in doubt.
sec=h8 h=b1b83d29d236sec=h6 h=c778f65a11ebc5 verified · fact Touch voltage on enclosure proposed
An improper bond can energize equipment chassis and metal piping.
sec=h8 h=b1b83d29d236sec=h6 h=c778f65a11ebverified by: review-workflowverified on: 2026-10-24review note: support check: partial - Passages say improper bonding can electrify equipment chassis and metal piping, but they never mention touch voltage on an enclosure as a symptom by name; the relation is implied.