GE IC695ETM001 Manual page 15

RX3i Ethernet Interface Module IC695ETM001-HV IPI
February 2016
Subject
Advanced User Parameter
wsnd_buf should not be
changed
Heavy load can block Station
Manager
One-time delay of EGD
Production (and possibly
Consumption) if more than 24
SRTP Server connections are
started simultaneously
Very heavy EGD
production/consumption at
server may cause EGD
command timeouts
SRTP Application Timeouts
must accommodate network
connection overhead
Client Channels and
Redundant IP
Idle Modbus/TCP connection
between a Series 90 and a
PACSystems may be
prematurely terminated
Attempt to open 17 or more
Modbus server connections
may appear successful
Ethernet Operational Notes
The Advanced User Parameter "wsnd_buf" should not be changed.
Changing this value may cause the LAN LED to go out and the Ethernet
Interface to drop connection.
As explained in PACSystems TCP/IP Station Manager Manual, GFK-2225,
Chapter 1, a heavy EGD and/or SRTP load can block Station Manager
operation.
If more than 24 SRTP Server connections are established simultaneously,
EGD Production may be briefly delayed for each connection after the 24th
when the connections are first made after power is applied. If EGD
consume acceleration has been disabled, then EGD Consumption is also
delayed. The delay only occurs once when the SRTP Server connection is
established for the first time after Powerup. No delay is experienced for
the first 24 SRTP Server connections.
Very heavy EGD production and/or consumption at a server device may
cause EGD command timeout errors when another device attempts to
send EGD commands to that server. If EGD commands must preempt
normal production, you may set the "gcmd_pri" Advanced User Parameter
to 2 (see GFK-2224, Appendix A). Note that by doing so, EGD exchange
production may be delayed.
The application timeouts within SRTP Channels also include the time
needed to establish and maintain the underlying network and STRP
connection. Examples are establishing the TCP connection for a new
channel, establishing communication with the remote device, and TCP
retransmissions during Channel operations. If the time needed for TCP
connection establishment or maintenance exceeds the user-specified
channel application timeout values, an application timeout will occur.
Channel application timeouts are temporary errors; the channel continues
to run.
In a Redundancy System, Client Channel COMMREQs can only be initiated
from the unit that owns the Redundant IP address. Therefore, the user
application logic should use Bit 6 in the LAN Interface Status bit area,
"Redundant IP Active" as part of their enabling logic that drives a client
channel COMMREQ.
An idle Modbus/TCP connection between a Series 90 controller and the
PACSystems Ethernet Interface may be prematurely terminated. There is
an incompatibility between the TCP "Keep-Alive" timer values on the
PACSystems Ethernet Interfaces and Series 90 Ethernet Interfaces. The
default value of the keep-alive timer for the Series 90 modules is set to a
much higher value than for the PACSystems. To keep TCP connections
open between a Series 90 Ethernet Interface and a PACSystems Ethernet
Interface, the Series 90 Interface Advanced User Parameter wkal_time
should be set to the value 750 to match that of PACSystems. With this
change, TCP connections remain open indefinitely. This also applies to
SRTP Client Channels that have infrequent traffic and can be resolved by
using the same technique.
If more than the maximum 16 supported Modbus Server Connections are
attempted, the TCP connection may succeed, but no data may be
subsequently transferred.
Description
15
GFK-2332W