Omron CQM1 Operation Manual page 74

Transmission Delay Time
Reducing Transmission
Delay Time
Existing System
Unit 1
Transmission delay time (Slave I/O delay time = 1.5 ms)
Tmax = ((28+2+2) x 1.2 x 2 ) + 1.5 = 78.3 ms
Modified System
System 1
Input Slaves 8 x 4-point,
total 32 points
4-point
input
Slave
System 2
Input Slaves 8 x 4-point,
total 32 points
4-point
input
Slave
Transmission delay time (Slave I/O delay time = 1.5 ms)
Tmax = ((14+0+2) x 1.2 x 2 ) + 1.5 = 39.9 ms
Refer to the CQM1H Operation Manual (W363) or the CQM1 Operation Man-
ual (W226) for details about the CQM1H/CQM1 and unit response times.
Refer to I/O Terminal Series Catalog (X044) for details about the Slave I/O
ON/OFF delay times.
For the system shown in the word allocation example on page 53, the time
(Tmax) between the input type Slave input signal turning ON, being read by
the Slave, and then being read by CQM1H/CQM1 from the Master is calcu-
lated as follows (assuming the Slave input ON delay time is 1.5 ms.).
Example calculation of transmission delay time:
The maximum transmission delay time (Tmax) for a system comprising seven
Slaves and one Expansion Master is Tmax = (7+1+2) x 1.2 x 2 + 1.5 = 25.5
ms.
The transmission delay time can be reduced by replacing a large system
using multiple Expansion Masters with multiple Masters configured as sepa-
rate systems.
Unit 2
Input Slaves 16 x 4-point,
total 64 points
4-point 4-point
input input
Slave Slave
4-point 4-point
input input
Slave Slave
4-point 4-point
input input
Slave Slave
Using one 16-point Unit instead of two 8-point Units reduces the number of
Units, and therefore decreases the transmission delay time.
Output Slaves 8 x 4-point +
4 x 8-point, total 64 points
4-point 4-point
input output
Slave Slave
Output Slaves 4 x 4-point +
2 x 8-point, total 32 points
4-point 4-point 8-point
output output output
Slave Slave Slave
Output Slaves 4 x 4-point +
2 x 8-point, total 32 points
4-point 4-point 8-point
output output output
Slave Slave Slave
Section 4-3
4-point 8-point
output output
Slave Slave
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