Grounding and Bonding Requirements for EV Chargers in New York
Grounding and bonding are foundational electrical safety requirements that apply to every EV charger installation in New York, from residential Level 1 outlets to commercial DC fast charging stations. These requirements are governed by the National Electrical Code (NEC), New York State Building Code, and — in New York City — the New York City Electrical Code. Proper grounding and bonding prevent electric shock, equipment damage, and fire hazards by establishing controlled fault-current paths and eliminating dangerous voltage differentials between conductive surfaces. This page covers the technical definitions, applicable code citations, common installation scenarios, and the boundaries that determine which grounding and bonding methods apply to specific EV charging equipment.
Definition and scope
Grounding and bonding are related but distinct concepts under electrical code. Grounding establishes an intentional connection between an electrical system or equipment and the earth, providing a reference point for voltage and a path for fault current to flow safely to ground. Bonding connects conductive parts of an installation — enclosures, conduit, equipment chassis — to ensure they share the same electrical potential, eliminating voltage differences that could cause shock if a person touches two surfaces simultaneously.
For EV charger installations, the NEC Article 625 — which governs electric vehicle power transfer systems — sets baseline grounding and bonding requirements that New York has adopted through the New York State Uniform Fire Prevention and Building Code. NEC Article 250 provides the overarching grounding and bonding rules, and Article 625 references Article 250 directly for equipment grounding conductor sizing, grounding electrode connections, and bonding of metallic enclosures.
New York's adoption of the NEC is administered through the New York State Department of State, Division of Building Standards and Codes. The regulatory context for New York electrical systems outlines how the state code adoption cycle works and which NEC edition is currently enforced statewide versus in New York City.
Scope of this page: This page applies to EV charger grounding and bonding requirements under New York State jurisdiction, including New York City where the NYC Electrical Code (which tracks the NEC with local amendments) governs. It does not address federal workplace installations regulated solely by OSHA, nor does it cover marine, recreational vehicle, or off-grid solar-only systems. Equipment installed in jurisdictions outside New York State falls outside the coverage of this analysis.
How it works
Grounding and bonding for EV charger circuits operate through a structured system of conductors and connections:
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Equipment grounding conductor (EGC): Every EV charger branch circuit must include an EGC sized per NEC Table 250.122, based on the circuit's overcurrent protective device rating. For a 50-ampere circuit — the most common Level 2 EVSE circuit — the minimum EGC is a 10 AWG copper conductor under NEC 250.122.
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Grounding electrode system: The EGC connects at the panel to a grounding electrode system (NEC Article 250, Part III), which must include a grounding electrode conductor running to the building's grounding electrode — typically a ground rod, concrete-encased electrode (Ufer ground), or water pipe electrode meeting NEC 250.52.
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Bonding of metallic enclosures: Any metallic conduit, junction box, or EVSE enclosure in the circuit must be bonded to the EGC. If metallic conduit (EMT, rigid, or IMC) is used as the wiring method, the conduit itself can serve as the EGC if all fittings are listed and properly installed per NEC 250.118.
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EVSE chassis bonding: The EVSE unit's chassis and any exposed conductive parts must be bonded to the equipment grounding conductor. NEC 625.10 requires that the EVSE's grounding terminal be connected in a manner consistent with the unit's listing and the applicable wiring method.
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Vehicle connector ground pin: NEC 625.10 also specifies that the EV connector's ground contact must be the first to make and the last to break during connection and disconnection, reducing the risk of energized connections.
Understanding how these layers interact requires familiarity with the broader conceptual overview of New York electrical systems, including how branch circuit wiring methods affect grounding conductor selection.
Common scenarios
Residential Level 2 installation (240V, 50A circuit):
In a typical residential garage installation, a 50-ampere circuit supplies a Level 2 EVSE. NEC 250.122 requires a 10 AWG copper EGC. If the installer uses PVC conduit, a separate 10 AWG green or bare copper EGC must be pulled through the conduit alongside the ungrounded and grounded conductors. If the installer uses EMT conduit with listed fittings throughout, the metallic conduit system itself qualifies as the EGC under NEC 250.118(4), eliminating the need for a separate wire EGC inside the conduit.
Outdoor pedestal-mounted charger (commercial parking lot):
Outdoor EVSE in commercial installations — such as those covered in detail on commercial EV charger electrical system design in New York — typically run underground circuits in PVC or rigid nonmetallic conduit. In this configuration, a separate copper EGC is mandatory. Additionally, if the outdoor installation is in a wet location, NEC 625.15 requires the EVSE to be listed for outdoor use, and the enclosure must be bonded to the EGC at the unit's listed grounding terminal.
Multifamily building EV-ready conduit systems:
New York Local Law 55 of 2022 and related state EV-ready building requirements mandate conduit infrastructure in new multifamily construction. For pre-wired conduit pathways, bonding continuity must be maintained through all junction points even before EVSE equipment is installed, because future electrical connections will rely on the existing bonded pathway. This is addressed in detail for multifamily building EV charger electrical infrastructure in New York.
Parking garage installations:
Parking structures present unique bonding challenges because of extensive metallic structural steel and reinforcement. NEC 250.104 may require bonding of structural steel to the grounding electrode system when that steel is within 5 feet of the grounding electrode conductor. Parking garage EV charger electrical considerations in New York covers how these structural bonding requirements interact with EVSE circuit design.
Decision boundaries
The following distinctions determine which grounding and bonding methods apply to a specific installation:
Wiring method determines EGC type:
- PVC or nonmetallic conduit → separate listed copper EGC required inside conduit, sized per NEC Table 250.122
- EMT, rigid, or IMC metallic conduit with listed fittings → metallic conduit qualifies as EGC per NEC 250.118; separate wire EGC optional but not required
- Type NM cable (Romex) → the bare copper ground wire within the cable assembly serves as the EGC; NM cable is generally not permitted in commercial or multifamily applications in New York City under the NYC Electrical Code
Location classification affects bonding requirements:
- Indoor dry locations → standard EGC bonding per NEC 250 applies
- Outdoor or wet/damp locations → EVSE must be listed for the environment; bonding applies identically but conduit seal requirements (NEC 225.22, 230.54) may add conduit sealing points that must maintain bonding continuity
Voltage level affects grounding electrode conductor size:
DC fast chargers operating at 480V or higher require larger grounding electrode conductors. NEC Table 250.66 governs grounding electrode conductor sizing based on the largest ungrounded service entrance conductor. A 200-ampere, 480V service for a DC fast charger installation would require a 2 AWG copper grounding electrode conductor at minimum.
New York City versus rest of state:
The NYC Electrical Code, administered by the NYC Department of Buildings, adopts the NEC with amendments. One key difference: New York City prohibits Type NM cable in most occupancies, which eliminates that wiring method — and its associated EGC provisions — from NYC EVSE installations. Outside New York City, the New York State Uniform Code governs, and NM cable may be permitted in one- and two-family dwellings.
All grounding and bonding work for EVSE installations requires a permit in New York, and the completed grounding system is inspected as part of the rough-in and final electrical inspection. The New York State EV charger electrical permit process outlines how grounding inspection checkpoints fit within the broader permitting sequence. Inspectors verify EGC sizing, grounding electrode connections, and equipment bonding against the applicable NEC edition adopted by the jurisdiction.
The EV charger electrical inspection checklist for New York identifies the specific grounding and bonding items that inspectors examine at rough-in and final stages, including verification of EGC continuity and proper termination at both the panel and EVSE chassis.
For installations where the main electrical panel or service entrance is involved — such as when a new grounding electrode system is required — the electrical service entrance upgrades for EV charging in New York page covers how service-level grounding changes interact with branch circuit EGC requirements.
The site home provides a structured entry point for navigating all EV charger electrical topics organized by installation type and regulatory category.
References
- [NEC Article 250 — Grounding and Bonding (NFPA 70, 2023 edition)](https://www.nfpa.org/codes-and-standards/n