That is for simple single panel installations.
Electrical panel neutral and grounding.
The panel that s located directly after the electric meter is the main service panel.
There are several different ways main panels are configured in homes here it is in a nutshell.
The main bonding jumper provides a ground connection between the neutral ground bus and the service panel.
The code defi nes bonded or bonding as connected connecting to establish electrical continuity and.
Three wires come from the electric meter and go into the main panel.
Neutral is a circuit conductor that normally completes the circuit back to the source.
This is a brief walk through of a simple grounding and bonding system and what happens with the flow of current in normal operation and in a ground fault c.
A second panel or sub panel should have the neutral and ground terminals or bars isolated from each other this is why the main circuit feed to the sub panel must have 4 wires with a dedicated insulated wire for the neutral and a separate wire for the ground.
Neutral is usually connected to ground earth at the main electrical panel street drop or meter and also at the final step down transformer of the supply.
Grounding a sub panel.
Basically grounding is connecting to the earth.
Another ground connection is made by the grounding electrode conductor or gec.
The ground bar is bonded internally when an external bond to earth is installed as described at the link for electrical grounding below.
For multiple panels the situation is more complex.
The code defi nes grounding as the connecting to ground or to a conductive body that extends the ground connection and the code defi nes ground as the earth.
Main panels and sub panels.
When grounding an electrical panel the following applies grounding a main panel.
If your electrical panel is the first service disconnect point and the utility has only provided normally current carrying conductors phase and neutral wires plus a ground wire then no you do not make a neutral to ground connection.
This is a bare copper wire that connects the neutral ground bus bar to a ground rod driven into the earth near the service panel or to metal rebar in the home s.
The tripped breaker shuts off the circuit s current preventing a potentially dangerous situation.
Two live hot wires and one neutral.
By shunting excess line voltage back to the panel s neutral pole the ground current forces the circuit breaker to trip.
Please see nec article 250 28 for when to make a neutral to ground connection.