AH500 Hardware and Operation Manual 
 
  Constant Scan Enable 
 This sets the minimum scan cycle time. 
 Disable: Disables this function. 
 Enable: When the actual scan cycle time is less than the setting time, the CPU module waits until the   
  setting time is met, and then starts the next scan. When the actual scan time is longer than   
  the setting time, the CPU module starts the next scan after the actual scan time completes. 
 
  Constant Scan Time 
If you selected Enable in the previous option, you set the scan cycle time here. If the actual scan time is   
 less than the setting time, the CPU module waits to begin the next scan until the setting time is met. If the     
 actual scan time is larger than the setting time, the CPU module ignores the setting time and operates   
 according to the actual scan time. If you set the scan time longer than the watchdog timeout set, a   
 watchdog timeout occurs when the CPU module operates. 
 
  Interval Interrupt Time 0~3 
An AH500 series CPU module provides four interrupts. You can set intervals of triggering the interrupts in 
Task, corresponding to Task252~255.   
 
  Remote Run Enable 
If the Enable Remote Run checkbox is selected, you can specify an X device which controls the state of 
the CPU module. For example, the CPU module runs when the state of X0.0 is ON, and the CPU module 
stops running when X0.0 is OFF.   
 
  Communication Loading of Scan Time 
If the Communication Loading of Scan Time checkbox is selected, you can specify the ratio of 
communication and scan time. Currently this function is only available for AH5x1 and AH560 Series.   
 
  Redundancy 
Currently this function is only available for AH560 Redundancy Series. Once this function is enabled, the 
backplane here will be changed to extension backplane automatically. And you will find two main 
backplanes in the Hardware Configuration area. The right backplane is the mirrored version of the left 
backplane. Thus you can NOT add, remove, or modify the backplane on the right. Refer to AH560 
Redundancy System Operation Manual for more information.