
BusWorks® 965EN Module User’s Manual Modbus TCP/IP mV/TC Input
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This module includes special messaging functionality (i2o, input-to-output
communication) that allows it to send its input level to an output channel on
an Acromag 972EN-400x or 973EN-400x analog output module. The I/O
Mapping page is used to specify the static IP address of the 972/973EN
module to send input data to, the specific Holding Register address of that
module (which channel), an update rate, and to set the scaling.
IMPORTANT:
This module is designed to function as a Modbus TCP/IP
slave/server. Normally, Modbus servers are not allowed to initiate messages
on their own and may only respond to client/master requests. The I/O
mapping function is a special application that may cause confusion for
master/client devices linked to the same network. Other master devices
should be restricted from attempting to control i2o target devices.
Each input channel of this device may be mapped to one or two output
channels of Acromag 972EN-400x (current output), or 973EN-400x (voltage
output) modules. The output channel that is to be controlled in this manner
is determined by the Map-To Holding Register address specified. The data
written will be scaled to percent-of-span units. Subsequent messages will be
sent at a periodic rate specified via the update time. Note that the target
output channels may still be controlled independently, but their level will be
overwritten by subsequent mapped messages when enabled.
WEB BROWSER
I/O Mapping Page
(Optional i2o Function)
This messaging function works
best if the target module(s) are
already online and ready to
receive messages. It will still
work if the target output
modules come online after the
input module, but may take
several minutes to “discover”
all the network targets and
begin transmitting to them.
If the input module or the
target module(s) go offline,
remote messaging will resume
on its own when the
connection is re-established,
but this “healing” function may
take several minutes
depending on which device(s)
went offline, why, and for how
long.
Note: Remote messaging
may only be configured via the
built-in web browser page as
there are no Modbus registers
for specifying these
parameters.