Axis limit switches are overtravel switches that, when tripped, cut power to the servo motors and should be located 2 or 3 degrees beyond the software limits.

• A. They should be located exactly at software limits
• B. They do not affect power
• C. False
• D. True

Answer: (D)

Limit switches act as a safety boundary for each axis. When such a switch trips, it cuts power to the servo motors, producing an immediate stop to protect the machine from damage. Placing these overtravel switches a small distance beyond the software limits creates a protective margin that accounts for timing delays, inertia, and mechanical tolerance. If motion heads toward a software limit, the hardware switch will trip first, ensuring power is removed before the axis reaches the software limit or the hard stop. The 2 or 3 degrees beyond the software limit is a practical gap to guarantee a safe shutdown under real-world conditions. That’s why this statement is true: the switches are safety devices that cut power, and they are placed beyond the software limits to provide that margin.