Omron R88D-1SN ECT Series, User Manual, Page: 458 / 974

5 EtherCAT Communications
5 - 20 AC Servomotors/Servo Drives 1S-series with Built-in EtherCAT® Communications User’s Manual (I586)
5-9 Cable Redundancy Function
Configuring a ring topology on the EtherCAT system enables communications to continue even if an
EtherCAT physical layer link is disconnected in the ring topology. This function is available for the unit
version 1.3 or later.
Possible causes for the ring disconnection status in which an EtherCAT physical layer link is discon-
nected are as follows:
• An EtherCAT communications cable is disconnected, loose, broken, or short-circuited.
• Failure of the EtherCAT physical layer of a Servo Drive
When the cable redundancy function is used on the Machine Automation Controller NJ/NX Series,
make the following settings.
When you build a safety system using FSoE communications, you also need to set the following item.
As for the detail, refer to the
NX-series Safety Control Unit User’s Manual (Cat. No. Z930).
This function enables communications to continue even if a cable is disconnected or broken in a ring
topology and the ring disconnection status results. A communications error may occur immediately
after the ring disconnection status occurs or during restoration from the ring disconnection status, and
cause all Servo Drives to detect EtherCAT Communications Warnings temporarily. When an EtherCAT
Communications Warning occurs, the communications error period command correction function cor-
rects the target position. Refer to
7-14 Communications Error Period Command Correction Function on
page 7-50 for details.
Even when the cable is disconnected from the ECAT IN connector on the Servo Drive B and the ring
disconnection status results as in the figure below, all Servo Drives can continue communications. If an
EtherCAT communications cable is disconnected, protect the disconnected connector.
5-9-1 Objects Requiring Settings
Index (hex)
Subin-
dex (hex)
Name
Recom-
mended
setting
Description
2200 00 Communications Error
Setting 2 or more Set the value at least two larger than the
default value because one communications
error occurs when the ring is broken or during
the restoration. The default value is 1.
Item Recommended setting Description
Watchdog Time of Safety Pro-
cess Data Communications Set-
tings Auto set value + EtherCAT
communications cycle × 2
or more
*1
*1. If EtherCAT communications cycle × 2 is less than 3 ms, add 3 ms or more to the auto set value.
Make the value at least two communications
cycles larger than the auto set value because
one communications error occurs when the ring
is broken or during the restoration.
5-9-2 Description of Operation