This past summer, the facility incurred repeated episodes of unplanned shut down due to cable failures. The plant manager understandably wants a solution. He asked you if there’s some way to test the cables to see which ones are weak. That’s an interesting question, since your last requisition for an insulation resistance tester was turned down. What should be your recommendations to solve this problem permanently?
A plant that doesn’t have a cable testing program with trending of the results of regularly scheduled testing is living on borrowed time. Kick things off by bringing in an electrical testing firm to design and implement a cable testing program that follows industry standards. Look for a firm with third-party certification, testing association membership, and technicians with documented training in electrical testing.
The cable testing addresses only the symptom-spotting part of the problem. Find out why those cables are being damaged. The most common cause of cable damage is the transient event, something you can capture on that new power monitoring system your plant manager should be happy to sign for.
Design a tiered surge protection system; one with progressively lower energy levels of protection as you go from the service toward the final load. There’s no single-rating device that can provide complete protection.
