Why Pipe to soil potential should be in the range -0.85Volt's to -1.25Volt's?

The pipe-to-soil potential should be in the range of -0.85 volts to -1.25 volts to ensure effective cathodic protection for underground pipelines. This range helps prevent corrosion by ensuring that the potential difference is sufficient to inhibit the electrochemical reactions that lead to corrosion, while also avoiding overprotection, which can cause hydrogen embrittlement. Maintaining this optimal potential range is crucial for the longevity and integrity of the pipeline infrastructure.