Specifications

Advanced Configuration Features
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In most cases, an output module that has one of its channels dedicated to a reflex
action goes to its configured fallback state if the module loses communication with
the fieldbus master. The only exception is a two-channel digital output module that
has both of its channels dedicated to reflex actions. In this case, the module may
continue to solve logic after a loss of fieldbus communication. For more information
about reflex actions, refer to the Reflex Actions Reference Guide.
Configured Fallback
To define a customized fallback strategy for individual modules, you are required to
use the Advantys Configuration Software. Configuration is done channel by
channel. You can configure a single module’s multiple channels with different
fallback parameters. Configured fallback parameters (implemented only during a
communications interruption) are part of the configuration file stored in the NIM’s
non-volatile Flash memory.
Fallback Parameters
You can select either of two fallback modes when configuring output channels with
the Advantys Configuration Software:
z hold last value: In this mode, outputs retain the last values they were assigned
before the fallback condition was triggered.
z predefined value: In this (default) mode, you can select either of two fallback
values:
z 0 (default)
z some value in acceptable range
The permissible values for fallback parameters in the predefined value mode for
discrete and analog modules and reflex functions appear in the following table:
NOTE: In an auto-configured system, default fallback parameters and values are
always used.
Module Type Fallback Parameter Values
discrete 0/off (default)
1/on
analog 0 (default)
not 0 (in range of acceptable analog values)