In March 2002, Spectrum Technologies provided 20 Class 1 E safety related
Cutler-Hammer A2001
NEMA Size 1 starters to Rochester Gas & Electric Company - Ginna Station. Spectrum Technologies had purchased the starters as
commercial grade items from
Cutler-Hammer, and dedicated them per
EPRI NP5652, method 1, Special Tests and Inspections.
Ginna Station advised Spectrum Technologies that they had installed one of these starters in the circuit for their Boric Acid Storage Tank (BAST) Heaters. Approximately eight (8) weeks later they received an alarm for low BAST temperature. Investigation found an open coil on the starter and replaced the starter. The failed starter was sent to the Ginna Materials Laboratory for analysis. This analysis indicates that a manufacturing defect caused the failure.
The Ginna Materials Laboratory examined the starter using a low power binocular microscope for signs of defects, overheating, or cracks. Resistance measurements between the two coils in the starter were taken and they were then subjected to X-ray radiography. Subsequent to this, the coils were disassembled and sectioned to reveal the defect. The failed coil wire was also examined using scanning electron microscopy for signs of overheating or melting.
It was determined that the failure is the result of a manufacturing defect in the epoxy surrounding the coil. The open circuit was caused when the epoxy cracked at the defect and broke a wire running through the epoxy. This wire connected the two coils and this failure caused the open circuit.
Spectrum Technologies has provided the above information, including all figures, to
Cutler-Hammer for them to investigate/evaluate the situation. Spectrum Technologies has requested that they provide a formal report addressing what caused the condition and whether it is unique or a common problem, what other components may be affected, and what will be done to prevent recurrence.