High-Speed Counter Frequency Measurement - Omron CP1L-EL20DR-D Operation Manual

High-speed Counters
Restrictions

High-speed Counter Frequency Measurement

Procedure
1,2,3...
Restrictions
Specifications
When the High-speed Counter Gate Bit is turned OFF again, the high-speed
counter will resume counting and the counter PV will be refreshed.
• The Gate Bit will be disabled if the high-speed counter's reset method is
set to Phase-Z signal + Software reset and the Reset Bit is ON (waiting
for the phase-Z input to reset the counter PV.)
This function measures the frequency of the high-speed counter (input
pulses.)
The input pulse frequency can be read by executing the PRV(881) instruction.
The measured frequency is output in 8-digit hexadecimal and expressed in
Hz. The frequency measurement function can be used with high-speed
counter 0 only.
The frequency can be measured while a high-speed counter 0 comparison
operation is in progress. Frequency measurement can be performed at the
same time as functions such as the high-speed counter and pulse output with-
out affecting the performance of those functions.
1. High-speed Counter Enable/Disable Setting (Required)
Select the Use high speed counter 0 Option in the PLC Setup.
2. Pulse Input Mode Setting (Required)
Set the High-speed Counter 0 Pulse Input Mode (Input Setting) in the PLC
Setup.
3. Counting Mode Setting (Required)
Set the High-speed Counter 0 Counting Mode in the PLC Setup.
If ring mode counting is selected, set the High-speed Counter 0 Circular
Max. Count (max. ring count) in the PLC Setup.
4. Reset Method Setting (Required)
Set the High-speed Counter 0 Reset Method in the PLC Setup.
5. PRV(881) Instruction Execution (Required)
N: Specify the high-speed counter number. (High-speed counter 0: 0010)
C: 0003 (Read frequency)
D: Destination word for frequency data
• The frequency measurement function can be used with high-speed
counter 0 only.
Item
Number of frequency
measurement inputs
Frequency measurement
range
Measurement method
Output data range
Specifications
1 input (high-speed counter 0 only)
High-speed counter 0:
Differential phase inputs: 0 to 50 kHz
All other input modes: 0 to 100 kHz
Note: If the frequency exceeds the maximum value, the
maximum value will be stored.
Execution of the PRV(881) instruction
Units: Hz
Range:
Differential phase input: 0000 0000 to 0003 0D40 hex
All other input modes: 0000 0000 to 0001 86A0 hex
Section 7-1
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