Omron NX-ECC201 User Manual page 260

12 Communications Performance
 Tmax-OutTrans
This is the longest output transmission time of the EtherCAT Coupler Units in all of the EtherCAT
Slave Terminals in the same EtherCAT network.
The output data transmission time is the time that is required for the EtherCAT Coupler Unit to read
the output data from the EtherCAT communications path and send the data to the NX Units.
With synchronous I/O refreshing, the data transmission is completed before the Sync0 timing.
Use the following formula to find Tmax-OutTrans.
Formula: Tmax-OutTrans = Max(T#1-OutTrans,
"Max" indicates the maximum value in the parentheses.
*1. T#1-OutTrans is the output data transmission time of the EtherCAT Coupler Unit in the EtherCAT Slave
Terminal with node address 1.
*2. T#2-OutTrans is the output data transmission time of the EtherCAT Coupler Unit in the EtherCAT Slave
Terminal with node address 2.
*3. T#n-OutTrans is the output data transmission time of the EtherCAT Coupler Unit in the EtherCAT Slave
Terminal with node address n. "#n" indicates the node address of the EtherCAT Slave Terminal. "n" is the
address.
Use the following formula to find T#n-OutTrans.
Formula: T#n-OutTrans = 11.71 × (Integer quotient of total byte size
*1. This is the total byte size of the output data of the NX Units in the EtherCAT Slave Terminal.
*2. Round down the value that results from the calculation in parentheses to an integer. It is expressed as
follows with a Microsoft Excel function:
ROUNDDOWN(Total_byte_size_of_all_NX_Unit_output_data/32,0)
*3. This is the remainder. It is expressed as follows with a Microsoft Excel function:
MOD(Total_byte_size_of_all_NX_Unit_output_data/32,0)
*4. This is the number of NX Units for which there are I/O assignments to BOOL output data in the EtherCAT
Slave Terminal. For example, the NX-OD3121 meets this condition because it is an NX Unit that has
BOOL output data. However, the NX-OD4121 does not meet this condition because it is an NX Unit that
has BYTE output data.
*5. If there are no NX Units in the EtherCAT Slave Terminal that have I/O assignments to BOOL output data,
use 0 for the calculation in parentheses.
*6. This is the total number of NX Units in the EtherCAT Slave Terminal.
12 - 6
+ 0.46 × (Remainder of quotient of total byte size *1 of the NX Unit output data ÷32)
+ (0.19 × Number of NX Units with BOOL output data
+ 0.38 × Number of NX Units
+ 0.014 × Total bytes size of NX Unit output data *1
+ 30.40
*1 *2
T#2-OutTrans, ...T#n-OutTrans
*1
of the NX Unit output data ÷32)
*4
*6
NX-series EtherCAT Coupler Unit User's Manual (W519)
*3
*5
+ 2.93)
(Unit: μs)
*2
*3