8. FUNCTIONS
IMS01J02-E2
174
8.2.2 Measuring method
Can be selected periodic computation method or pulse count method.
Periodic computation method
Frequency is obtained by measuring the time required for certain pulse intervals. The number of
measured pulses can be set in the pulse range of 1 to 1000 by setting divide ratio.
Setting range
H-SIO-A divide ratio: 1 to 1000
Example: When divide ratio is set to 3.
The input value is updated every 100 ms. It is also updated every 100 ms even at a
measuring time of less than 100 ms.
If the number of pulses set by divide ratio cannot be detected within the H-SIO-A auto zero time, this
is assumed to be pulse stop and thus the input value is set to the low limit value on the display scale.
Setting range
H-SIO-A auto zero time: 1 to 100 seconds
Pulse count method
Frequency is obtained by counting the number of pulses input within the gate time.
Setting range
H-SIO-A gate time: 0.1 to 4.0 seconds
Example: When gate time is set to 1.0 second.
5
4
3
2
1.0 second
(Gate time)
1
100
99
98
97
96
Input 100 pulse per 1.0 second
100
= 100 Hz
1.0 second
Measuring time of 3 pulse is 30 ms
Divide ratio 3
= 100 Hz
30 ms
3
2
Start
30 ms
1
