Rockwell Automation 1753-DNSI DeviceNet Safety Scanner for GuardPLC Controllers - Manual (Page 14)

Publication 1753-UM002A-EN-P - July 2005
1-4 Before You Begin
How Data Tables Work
To exchange data, the GuardPLC controller and the 1753-DNSI use
two pairs of data tables: one pair for safety input and output data and
one pair for standard input and output data.
Standard DeviceNet Explicit Messaging connections are limited to
read-only access to safety data.
How to Distinguish Between Standard Data and Safety Data in
RSLogix Guard PLUS!
In the HSP Signal Connection dialogs (in RSLogix Guard PLUS!),
signals that are transferred over safety connections are shown in white
text on a red background. Signals transferred over a standard
connection are shown in blue text on a gray background.
Connection Type Scanner Inputs Scanner Outputs
Safety
Scanner is the
originator. Data the scanner reads from
its target nodes. The data
layout is defined by the
target node’s configuration. Data the scanner writes to
its target nodes. The data
layout is defined by the
target node’s configuration.
Scanner is the
target. Data that one other CIP
Safety originator may write
on the scanner’s target
output connection point. The
data signals to be written
are selected in RSLogix
Guard PLUS!. Data that one or more other
CIP Safety originators may
read from the scanner’s
target input connection
point. The data signals to be
read are selected in RSLogix
Guard PLUS!.
Standard
Scanner is the
master. Data the scanner reads from
its standard DeviceNet
slaves. The data layout is
defined by the target node’s
configuration. Data the scanner writes to
its standard DeviceNet
slaves. The data layout is
defined by the target node’s
configuration.
Scanner is the
slave. Data that one other
standard DeviceNet master
can write on the scanner’s
slave mode outputs. The
data signals are selected in
RSLogix Guard PLUS!. Data that one or more other
standard DeviceNet master
can read from the scanner’s
slave mode inputs. The data
signals are selected in
RSLogix Guard PLUS!.
ATTENTION
To maintain the safety integrity level (SIL) of your
system, you must ensure that safety data read by
Explicit Messaging is used only as standard data in
your application.