Mitsubishi MELSEC-Q Series User Manual page 213

5
PROCESSING TIME OF QCPU IN MULTIPLE CPU
SYSTEM
(b) Calculation of auto refresh time
Q02CPU
Q02HCPU, Q06HCPU,
Q12HCPU, Q25HCPU
Q02PHCPU, Q06PHCPU,
Q12PHCPU, Q25PHCPU
The automatic refresh time of the CPU shared memory is calculated in the
following equation.
1) For Basic model QCPU
(Auto refresh time)
= (N1 + (No. of transmission word points)
(N3 + (No. of other CPUs)
• The number of received words is the sum of the numbers of words
transmitted by the other CPUs.
(Example) When No. of CPU is set to 3 and the host CPU is CPU No. 1
The number of received words is the sum of the numbers of
words sent by CPUs No.2 to No.3.
• For N1 to N5, use the values in Table5.3.
Basic model QCPU
Q00CPU
Q01CPU
2) For High Performance model QCPU/Process CPU
(Auto refresh time) = (N1 + (No. of reception word points)
+ (N3 + (No. of transmission word points)
• The number of received words is the sum of the numbers of words
transmitted by the other CPUs.
(Example) When No. of CPU is set to 4 and the host CPU is CPU No. 1
The number of received words is the sum of the numbers of
words sent by CPUs No.2 to No.4.
• Use the values in Table5.4 for N1 to N4.
High Performance model
QCPU/Process CPU
Univwesal model QCPU
N2)) +
N4 + (No. of reception word points)
Table5.3 Auto refresh time
N1 N2
63 s 1.13 s
57 s 1.03 s
Table5.4 Auto refresh time
N1 N2
82 s 0.52 s
27 s 0.44 s
5.2 Factors for prolonged Scan Time
N5) (µs)
N3 N4 N5
63 s 161 s 0.88 s
57 s 146 s 0.80 s
N2) (No. of other CPUs)
N4) (µs)
N3 N4
106 s 0.17 s
27 s 0.08 s
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