Neutral Ampacity & Re-closers

Q: In Exhibit E of your proposal you state that cable replacement should be utilized rather than cable injection if the “cable neutral has lower than required ampacity …” I was able to find on Novinium’s website the limits for neutral corrosion, but nothing on the neutral ampacity limits. What are the neutral ampacity limits? Keep in mind that on three phase cable installs we use one-third neutrals. In Exhibit F of your proposal you define “Abnormal Operational Excursion(s).” One of the identified excursions, item (3), is “repeated operations of re-closers.” We use re-closers on all of our circuits. Does this mean that the warranty is void?

Neutral Corrosion Progression

Q: Can you please explain the rate of neutral corrosion? Specifically, do neutrals corrode linearly or in some other fashion? Also, an engineer asked me about stray voltage. We were discussing how Novinium will provide a warranty for a cable segment if 50 percent of the neutrals are good. He said, “Okay, but because of the neutral corrosion, I am having stray voltage issues affecting livestock on dairy farms. This can kill livestock. Stray voltage is also showing up sometimes on communications circuits.” How should I respond?

DC Testing to sectionalize faults – Warranty Impact

Q: We use a 10kV hipot DC to sectionalize URD faults. We actually use this on several sections at a time so it will go through good sections of cable until it reaches the bad section. We split the run of cables fed by a common fuse in half and hipot one way (could be 4 or 5 sections of cable) and if it is not found we hipot in the other direction. Do we have to wait 120 days after this and if so how do we track it?