AH500 Module Manual Count cycle Number of input pulse 1000 992 1002 Example: A flow counter is used. A pulse represents a flow of 5 cm 3 . The unit magnitude set is 1. Prescale value set: 5 Prescale function selected: 0 (x1) Count cycle: 0 (1 second) The figure above shows that the number of input pulses count during the first cycle is 1000. Number of sampled pulses =Number of pulses count during a cycle x Scale set by users x Magnification =1000x5x1=5000 (cm 3 /s) 3. Bit 2 in CR4/CR32/CR60/CR88: If bit 2 in CR4/CR32/CR60/CR88 is turned ON, the function of averaging the number of sampled pulses will be enabled.
If bit 2 in CR4/CR32/CR60/CR88 is turned OFF, the function of averaging the number of sampled pulses will be disabled. The function of averaging the number of sampled pulses prevents the number of pulses sampled in a cycle form being abnormal. Then number of pulses sampled in N cycles is divided by N. In the figure below, the number of pulses sampled in 3 cycles is divided by 3. Number of sampled pulses Count cycle 4 3 2 6 7 8 9 12 11 10 Buffer register Value stored at the first time Value stored at the second time Value stored at the third time Number of sampled pulses Time Buffer register for data conversion: Note: The number of pulses sampled in N cycles is divided by N.
7-22 Value stored at the first time 1 2 3 3 Value stored at the second time 2 3 4 3 Value stored at the second time 3 4 5 3 Item Value/Setting value Parameter CH0 CH1 CH2 CH3 Number of sampled pulses (Low word) -200000~200000 #20 #48 #76 #104 Number of sampled pulses (High word) #21 #49 #77 #105 Number of cycles 2~60 #7 #35 #63 #91