What action must be taken if insulation resistance test readings exceed acceptable limits?

When insulation resistance test readings exceed acceptable limits, the appropriate action is to repair the installation first. High insulation resistance readings generally indicate that the insulation is functioning adequately and is not likely to pose a risk of electrical leakage or short circuit. However, it is vital to understand that exceeding acceptable limits does not necessarily mean the insulation is defective; it can sometimes indicate a need for further investigation into the installation conditions or methods.

Thus, repairing the installation first ensures that any underlying issues that may lead to future faults are addressed. This may involve fixing any physical damage, properly fastening connections, or addressing environmental factors affecting the insulation integrity. Once the repairs are completed, subsequent tests can confirm whether the insulation resistance has improved and meets safety standards.

In contrast, the other options present various actions that may not align with best practices in electrical safety and compliance. For instance, replacing wiring immediately may not be necessary and would incur unnecessary costs. Documenting the readings and proceeding treats the situation as if there is no concern, ignoring the potential risks associated with compromised wiring. Ignoring minor excesses without evaluation can lead to unsafe conditions and potential system failures. Therefore, taking corrective measures by repairing the installation is the most appropriate response in this scenario.