Mitsubishi Electric MELSEC-Q Structured Programming Manual page 88

FXCPU Structured Programming Manual
[Device & Common]
2) In FX /FX
3G
Counter type
Software counter
C235, C236, C238,
1-phase
C239, C241
1-counting
C237, C240, C242,
input
C243, C244, C245
C246, C248(OP)
1-phase
2-counting
C247, C248, C249,
input
C250
C251, C253(OP)
2-phase
2-counting
C252, C253, C254,
input
C254(OP), C255
*1. Number of axes used in the following positioning instructions:
PLSY, PLSR , DSZR , DTBL , ZRN , PLSV , DRVI , DRVA
• Calculation of the total frequency
The total frequency is calculated using the following expression:
Total frequency ≥ (Sum of frequency used by 1-phase counters) + (Sum of frequency
used by 2-phase counters)
• Calculation example
Example1: When DHSCS, DHSCR or DHSZ instruction is not used, and instructions related to positioning
(DRVI instruction [Y000] and DRVA instruction [Y001]) are used
Overall frequency: 200 kHz - (2 axes × 40 kHz) = 120 kHz
<Counter No.>
C235 (1-phase 1-counting) :
C236 (1-phase 1-counting) :
C237 (1-phase 1-counting) :
C253 (2-phase 2-counting) :
Example2: When DHSCS, DHSCR or DHSZ instruction is not used, and instructions related to positioning
(DRVI instruction [Y000] are used, Number of pulse width/pulse period measurement
inputs(X003)
Overall frequency: 200 kHz - (1 axes + 1 input) × 40 kHz = 120 kHz
<Counter No.>
C235 (1-phase 1-counting) :
C236 (1-phase 1-counting) :
86
PLCs
3GC
Response
When DHSCS, DHSCR or DHSZ
frequency
instruction is not used
60kHz
10kHz
60kHz
200 kHz - (Number of positioned axes
pulse width/period measurement inputs) × 40 kHz
10kHz
30kHz
5kHz
Total115 kHz
Total100 kHz
Overall frequency determined by condition of instructions used
*1
+ Number of
<Contents of use>
50 kHz is input.
50 kHz is input.
10 kHz is input.
5 kHz is input.
120 kHz (Overall frequency)
<Contents of use>
50 kHz is input.
50 kHz is input.
120 kHz (Overall frequency)
2 Devices in Detail
2.7 High Speed Counter [C]
When DHSCS, DHSCR or DHSZ
instruction is used
60 kHz - (Number of positioned axes
(Number of pulse width/period measurement
inputs × 20 kHz)
*1
× 5 kHz)