Delta AH500 - Page 254

AH500 Module Manual
7-22
Number of input pulse
Count cycle
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
Buffer register
Number of
sampled pulses
Value stored at the first time
Value stored at the second time
Value stored at the third time
Note: The number of pulses sampled in N cycles is divided by N.
Value stored at
the firs t time
Value stored at
the second ti me
Value stored at
the second time
Buffer register for data conversion:
Time
333
1
12
11
6
7
8
9
10
5
4
3
2
1
2
2
3 3 3
4
4 5
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