Which statement correctly identifies the most common lifecycle count for IEC contactors?

• A. One million electrical operations
• B. Ten million electrical operations
• C. Ten million mechanical operations
• D. One hundred thousand electrical operations

Answer: (C)

The main idea here is that IEC contactors are rated for both mechanical life and electrical life, with the common, widely cited endurance being a high mechanical life. The mechanism can cycle many times without current flowing, so its wear is dominated by parts like springs, linkages, and the drive mechanism. That mechanical endurance is typically about ten million operations, which is why the most common lifecycle count is ten million mechanical operations. In contrast, electrical life—the number of cycles under load before the contacts wear or weld—is much lower because arcing and contact wear shorten life. So statements about one million electrical operations or ten million electrical operations reflect electrical life, not the usual mechanical endurance, and a much smaller figure like one hundred thousand electrical operations would be unusually low.