Bonding Jumper Size Calculator

Determine the minimum load-side bonding jumper size based on OCPD rating.

Inputs
Results
Minimum Bonding Jumper Size
6
Minimum Bonding Jumper Size6
OCPD Rating Used200 A

· Based on NEC Table 250.122 for 200A OCPD.

· Minimum equipment grounding conductor: 6 AWG copper.

· If conduit or cable armor serves as the EGC, verify continuity and suitability.

· Always verify against the current edition of the NEC and local amendments.

· This tool sizes load-side bonding jumpers per NEC Table 250.122. Supply-side bonding jumpers are sized per Table 250.66 / 250.102(C), which may require a larger conductor. Consult a licensed electrician for service entrance work.

How It Works

Bonding jumpers connect metal parts of an electrical system to ensure fault current has a low-impedance return path.

This calculator sizes load-side (equipment) bonding jumpers per NEC Table 250.122, based on the OCPD rating ahead of the circuit. Supply-side bonding jumpers (service entrance, separately derived systems) are sized per Table 250.66 / 250.102(C) and may require a larger conductor. Consult a licensed electrician for service entrance bonding.

Example

A 200 A OCPD requires a minimum 6 AWG copper load-side bonding jumper per NEC Table 250.122.

Frequently Asked Questions

Is this the same as the grounding electrode conductor?

No. The grounding electrode conductor (GEC) connects to the earth ground rod or other grounding electrode. Bonding jumpers connect metal parts together. Both are required but serve different functions.

What is an equipment bonding jumper?

A conductor that connects two metal parts of an electrical system to ensure continuity, for example between metal enclosures on opposite sides of a flex connector.

These numbers are for reference only. We are not liable for any decisions you make or how you use these results in the real world. Check the current NEC and your local codes, and have a licensed electrician sign off before you install or buy. Full disclaimer