It is normal for the voltages measured on the neutral line to be slightly elevated above the system’s ground due to current flow in the neutral to hot circuit.
The more load that is applied, the more current flow in the neutral wire and the more this voltage is elevated.
The difference is voltage drop due to the current flowing in the neutral line, due to its impedance, compared to no voltage drop in the ground line.
No current should be flowing in the ground line unless there is a ground fault condition, so some difference is to be expected under normal conditions.
It is usually only when equipment is very sensitive to these variations that this slight elevation would present a real issue.
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