What is the recommended maintenance test voltage for insulation resistance on a 3-phase rotating machine rated 5kV line-to-line per NETA standards?

The recommended maintenance test voltage for insulation resistance on a 3-phase rotating machine rated at 5kV line-to-line aligns with the specified range of 1000-2500V according to the NETA standards. Testing at this voltage range is effective and adequate for identifying insulation integrity and any potential failures without risking damage to the insulation system.

Using 1000-2500V ensures that the testing voltage is sufficient to produce reliable results while remaining within a safe range to avoid overstressing the insulation, which could lead to false readings or additional wear on the machine if tested at higher voltages. Such careful consideration is crucial in maintenance practices to ensure the longevity and reliability of electrical equipment.