Which statement about fiberglass hot sticks retesting is correct?

• A. Initial test at 75,000 V for 1 minute; retest at 100,000 V for 5 minutes
• B. Initial test at 100,000 V for 5 minutes; retest at 75,000 V for 1 minute
• C. Initial test at 50,000 V for 2 minutes; retest at 25,000 V for 1 minute
• D. Initial test at 120,000 V for 3 minutes; retest at 60,000 V for 2 minutes

Answer: (B)

Dielectric testing of fiberglass hot sticks uses a two-step voltage test to verify insulation integrity. The first step applies a high voltage for a longer period to stress the insulation and reveal any weak spots. If the stick withstands this, a second, lower-voltage test for a shorter duration confirms it will perform under normal operating conditions and that no damage occurred during the high-voltage test. For fiberglass hot sticks, the established sequence is to apply 100,000 volts for five minutes initially, then perform a retest at 75,000 volts for one minute. This order provides a rigorous stress test followed by a verification at a typical working stress. Other sequences either under- or over-test relative to this standard and don’t offer the same level of assurance about insulation integrity.