Frequency Measurement With Integration Time - Siemens SIMATIC ET 200S Operating Instructions Manual

1Count5V
3.7 Measurement Modes
3.7.3

Frequency measurement with integration time

Definition
In frequency measurement mode, the 1Count5V counts the pulses that arrive within a set
integration time.
Integration time
You preset the integration time with the integration time parameter (see table).
Table 3- 10 Calculation of the Integration Time
Boundary conditions
Non-isochronous mode
Isochronous mode
Any digits after the decimal point that come about after dividing by T
1
It is not permitted to violate these limits. If these limits are violated, the 1Count5V generates a parameter assignment error
and will not go into isochronous mode.
Frequency measurement
The value of the calculated frequency is made available in the unit 10
frequency value can be read in the feedback interface (byte 0 to 3).
Figure 3-24
170
Integration time
Any T n x 10 ms
DP
T < 10 ms n x T
DP
T ≥ 10 ms n x T
DP
Frequency Measurement with Gate Function
Range of n
n
min
1
(10 ms/T [ms]) +1
DP DP
1
DP
are omitted.
DP
Operating Instructions, 06/2010, A5E00124867-07
n
max
1000
1000
1
10000 ms/T [ms]
DP
Hz. The measured
-3
Technological Functions
1