Mitsubishi Electric Q80BD-J71BR11, User Manual

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MELSEC
9 UTILITY OPERATIONS
POINT
(1) Relation between link refresh interval value and delay time in data reading
The maximum delay time (T
D(MAX)
) from when link device data arrive at the
refresh data storage area on the MELSECNET/H board until they are read out
into the user program can be obtained from the following formula.
Maximum delay time, T
D(MAX)
= T
UP
+ (n-1) x T
LS
T
UP
: Interval for reading link device data from user program
n : Specified interval value
T
LS
: Link scan time
The following shows an example of accessing LB0 under conditions: T
UP
=
100ms, n = 3, T
LS
= 120ms.
The maximum delay time, T
D(MAX)
is:
T
D(MAX)
= 100ms + (3-1) x 10ms = 120ms
(n-1) T
LS
=20ms
T
UP
=100ms
T
D(MAX)
T
LS
=10ms
User program
Read timing
MELSECNET/H
driver buffer
Link refresh
(When n=3)
Refresh data storage
area (LB0)
Link scan
9.3 Device Monitor Utility
For the operation and setting method for the device monitor utility, refer to "MELSEC
Data Link Library Reference Manual".