The Automatic Changeover Switch (ACOS) Control Unit is designed to monitor the platform's normal and alternative supplies and select the optimum supply to be used.

The unit monitors voltage and frequency of the supplies and has adjustable setpoints :

• Under Voltage Set Point
• Under Voltage Differential (%)
• Under Frequency Set Point
• Under Frequency Differential (%)
• Over Frequency Set Point
• Over Frequency Differential (%)
• Dwell Time (S)
• Delay Time (S)