What happens to the voltage on the neutral if it is tied down?

When the neutral is tied down, it effectively means that the neutral conductor is connected or grounded at multiple points, which can create a situation where it carries less current under normal operating conditions. However, if there is an imbalance in the system—such as when a single-phase load is connected to a three-phase system—the potential can rise on the neutral due to the unequal sharing of load across the phases.

As the neutral carries the unbalanced load, and if there is an issue with grounding or if the system is not properly designed, the voltage measured on the neutral can indeed increase significantly. This increase can lead to unsafe conditions, as voltage on the neutral that is higher than expected may indicate problems in the electrical system, like overloading or improper grounding which may result in hazardous situations such as electric shock or equipment damage.

Therefore, tying down the neutral can lead to significant voltage rises if the system experiences an imbalance or if the neutral becomes overloaded.