A Quantum EIO system can detect the existence of communication loss in the following ways:
-
a cable that is broken or detached, which is detected by both the 140CRP31200 remote I/O head module and a CRA3120 remote I/O adapter module
-
a CRA3120 adapter module that has stopped communicating, which is detected by a 140CRP31200 head module
-
a 140CRP31200 head module in the CPU that has stopped communicating, which is detected by a CRA3120 adapter module
The time required by the system to detect each type of communication loss is described below.
Broken Cable Detection Time
A 140CRP31200 head module and a CRA3120 adapter module can detect a broken or detached cable within 5 ms of the occurrence.
NOTE: A network that includes up to 32 140CRP31200 head modules and CRA3120 adapter modules can recover communications within 50 ms from the time the cable break is detected.
NOTE: When a broken cable (another healthy cable is in place) is connected to a remote I/O Ethernet port, wait for the LINK LED (the status of the port) to appear before removing another cable in the system. If all links are broken simultaneously, the device goes into fallback state.
Remote I/O Drop Loss Detection Time
A 140CRP31200 head module can detect the communication loss of a CRA3120 adapter module within the time defined by the following formula:
Detection time = (xMultiplier * ) + (CPU scan time), where:
|
RPI (ms)
|
xMultiplier
|
|
2
|
64
|
|
3...4
|
32
|
|
5...9
|
16
|
|
10...21
|
8
|
|
≥ 22
|
4
|
For RPI details, refer to the Connection Parameters topic in the Quantum EIO Remote I/O Modules Installation and Configuration Guide.
Remote I/O Local Rack Head Module Loss Detection Time
A CRA3120 adapter module in a remote I/O drop can detect the communication loss of a 140CRP31200 head module within the time defined by the following formula:
Detection time = (xMultiplier * RPI) + (CPU scan time), where:
|
RPI (ms)
|
xMultiplier
|
|
2
|
64
|
|
3...4
|
32
|
|
5...9
|
16
|
|
10...21
|
8
|
|
≥ 22
|
4
|
For RPI details, refer to the Connection Parameters topic in the Quantum EIO Remote I/O Modules Installation and Configuration Guide.
