196
High-speed Counters Section 5-1
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.
Restrictions • 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.)
High-speed Counter Frequency Measurement
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.
Procedure
1,2,3...
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
Restrictions • The frequency measurement function can be used with high-speed
counter 0 only.
Specifications
Item Specifications
Number of frequency
measurement inputs
1 input (high-speed counter 0 only)
Frequency measurement
range
High-speed counter 0:
Differential phase inputs: 0 to 50 kHz
(J models : 0 to 10kHz)
All other input modes: 0 to 100 kHz
(J models : 0 to 20kHz)
Note: If the frequency exceeds the maximum value, the
maximum value will be stored.
Measurement method Execution of the PRV(881) instruction
Output data range Units: Hz
Range:
Differential phase input: 0000 0000 to 0003 0D40 hex
(Y models: 0000 0000 to 0007 A120 hex)
All other input modes: 0000 0000 to 0001 86A0 hex
(Y models: 0000 0000 to 000F 4240 hex)
To Next Page
Loading...
