Harris Institute of Technical Training

Why is it important that the neutral be bonded to all metering services?

Thanks

Let's start with 4-Wire WYE metering service: the neutral provides voltage balance between the three energized phases.
In the 4-Wire WYE system: the neutral provides the current return path for phase to neutral connected loads.
Now, let's look at the 3-Phase 3 Wire Delta which is a good example of a metering service that does not use a neutral. In this service type, a corner ground might be used by some utilities but it is not a neutral.

The purpose of bonding is to ensure that no metal parts become energized. This is achieved by either tripping the main breaker or melting down the wiring if before the main. Either is preferable to energized live parts causing an electrocution.