Rockwell Automation 1753-DNSI DeviceNet Safety Scanner for GuardPLC Controllers - Manual (Page 93)

Publication 1753-UM002A-EN-P - July 2005
Monitor Status 10-9
Connection Status You can monitor the HSP and DeviceNet Safety and standard
connection status using the scanner’s connection status bits and the
related GuardPLC application signals as discussed in the following
sections.
DeviceNet Connection Status Bit Behavior
The following table describes the combined operation of the
DeviceNet connection status bits.
Connection
Fault Idle Mode Safety Connection Operation Standard Connection Operation
0 = Valid 0 = Run Data is actively being controlled by the producing device. The producing device is in the Run mode.
0 = Valid 1 = Idle The connection is active and the producing device is
in the Idle state. The safety data sent to the
controller from this connection is reset to zero. The connection is active and the producing node is
in the Idle state. The data sent to the controller for
this connection is ‘hold last state’.
1 = Faulted
1 = Idle
(1) The connection is faulted. The state of the
producing device is unknown. The safety data sent
to the controller from this connection is reset to
zero.
A safety connection status bit is set to Faulted any
time the connection is not established or not
operating error-free.
Not applicable.
1 = Faulted
0 = Run
(1) Not applicable. The connection is faulted. The state of the
producing device is unknown. The data sent to the
controller for this connection is reset to 0. At start
up, the standard fault bit defaults to 0. If the first
attempt to connect to the slave device is not
successful, then the connection will be reported as
faulted. When one or more of the standard
connections to the slave node timeout, the
corresponding fault bit is set. When all of the
connections to a slave node are in the established
state, the fault bit is set to 0.
The fault bit for the slave-mode interface is not
used; it is always 0.
(1) This value is meaningless when the Connection Fault bit is 1 (Faulted).
IMPORTANT
The bits in the table above are only accurate if the
HSP connection is established.
IMPORTANT
As with any communications channel, you must use
the connection status bits in your application
program logic to achieve a SIL 3 system.