Grounding and Bonding (NEC)
If you work around electricity, you’ve heard the words grounding and bonding. They sound similar, but they do different jobs. The NEC (National Electrical Code) uses both to help stop shocks, fires, and equipment damage.
👉 If you want the big-picture first, start with our NEC Overview: What It Is and Why It Matters.
What Is Grounding?
Grounding means connecting part of an electrical system to the earth (ground).
Why grounding matters
Grounding helps:
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Keep voltage levels more stable
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Reduce damage from lightning or power surges
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Give extra protection for equipment
Simple way to think about it:
Grounding gives electricity a safe “reference point” to the earth so the system stays steady.
What Is Bonding?
Bonding means connecting metal parts together (like conduit, panels, and metal boxes) so they are all at the same electrical level.
Why bonding matters
Bonding helps:
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Make sure metal parts don’t become “secretly energized”
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Create a safe path for fault current to travel
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Make breakers trip faster during a fault
Simple way to think about it:
Bonding makes all metal parts “hold hands” so if something goes wrong, electricity has a clear path back and the breaker can shut it down.
The Big Difference (Super Important)
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Grounding = connection to earth
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Bonding = connection of metal parts to each other
Here’s the key:
✅ Bonding is what usually makes the breaker trip.
Grounding helps stabilize the system, but bonding is what helps clear faults fast.
What Happens During a Fault?
Let’s say a hot wire touches a metal electrical box.
If bonding is done right:
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The metal box is connected back to the panel through the equipment grounding path
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A lot of fault current flows quickly
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The breaker trips fast
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The danger stops
If bonding is NOT done right:
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The metal box can stay energized
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Someone touches it and gets shocked
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The breaker might not trip
Common Grounding and Bonding Parts You’ll See
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Ground rod (a metal rod driven into the earth)
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Ufer ground (concrete-encased electrode—very common in new buildings)
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Bonding jumper (connects metal parts together)
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Equipment grounding conductor (EGC) (green wire or bare copper)
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Grounding electrode conductor (GEC) (wire that connects the system to the grounding electrode)
Why This Matters for Commercial Jobs
In commercial buildings, there’s usually:
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Bigger services (more power)
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More metal conduit
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More panels and equipment
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More people in the building
That means grounding and bonding mistakes can cause:
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Bigger arc flash risks
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More expensive equipment damage
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Inspection failures
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Serious safety hazards
Why Labels Matter Too
Even when grounding and bonding are done correctly, electricians and inspectors still need to identify equipment and hazards fast.
✅ At Print Pro, we make NEC-compliant electrical labels that help keep jobs clear, safe, and inspection-ready—especially in commercial electrical rooms.
Pro Tips for Contractors (Simple but Important)
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Don’t mix up grounding and bonding—they’re not the same job
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Bonding is what helps the breaker trip fast during a fault
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Always double-check bonding on:
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Conduit connections
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Panel enclosures
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Service equipment
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Metal water piping
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If you ever think “the earth will clear the fault,” stop—bonding is the real path
