KEYENCE Visual KV Series - Manual (Page 268)

4.7 Examples of Direct Clock Pulse Output
3-244
Visual KV
Series
4
Chapter 4 High-speed Counters
■ Example
Count value
• Sets the pulse output from output relay 0501 with special utility relays 2204 through 2207.
In this example, turns OFF 2204 to enable direct output from 0501 and turns ON 2207 to
reverse the output each time the CTH1 value reaches the CTC2 value.
• Turns ON 2203 to set CTH1 to be cleared when its value reaches the CTC2 value.
With this setting, the operation which clears the CTH1 current value when it reaches the
CTC2 preset value is repeated.
• The RES CTH1 instruction resets the CTH1 current value when operation starts. This
ensures that the first clock pulse is output at the proper pulse width.
Turn ON the input enable relay for CTH1 all the time when CTH1 is used to output the
clock pulse.
Coding
Note :When the input enable relay for the high-speed counter is used to start/stop
the clock pulse, the response is delayed by a maximum of one scan when output
starts. Moreover, if the response is delayed by one scan when output stops, the
clock pulse stops but the output may remain ON.
■ Tips
•
Use special utility relay 2205 to control (enable/disable) the clock pulse output by
external inputs.
• Use the SET-RES pair or KEEP instruction to turn special utility relay 2205 ON/
OFF.
• With this setting, the clock pulse is always turned OFF when it starts as well as
stops.
• When either of the following programs is added to the example on the previous
page, the clock pulse is output from 0501 only when 0000 is ON.
When SET-RES instructions are used When KEEP instruction is used
0000
0000 2205
RES
2205
SET
0000
0000
RES
KEEP
2205
SET
CTC2
ON ON
y a l e r y t i l i t u l a i c e p S k c o l c l a n r e t n I e u l a v t e s e r p 2 C T C
0 0 2 2 0 . 1 µs 0 0 5
1 0 2 2 0 . 0 1 µs 0 5
2 0 2 2 0 . 0 0 1 µs 5
2203
SET
2204
RES
2205
RES
2206
RES
CTH1
RES
2008
2002
#00050
CTC2
CTH1
2201
0001
0002
0003
2207
SET
Line No. Instruction Operand Line No. Instruction Operand
0000 LD 2008 0008 CON
0001 SET 2203 0009 SET 2207
0002 CON 0010 CON
0003 RES 2204 0011 RES CTH1
0004 CON 0012 LD 2002
0005 RES 2205 0013 CTH 1 2201
0006 CON 0014 CTC 2 #00050
0007 RES 2206
KVNKA Chap 04_2.p65 08.3.11, 0:08 PM 244