Chapter
6
Operating Instructions
Flexi Soft Gateways
154
© SICK AG • Industrial Safety Systems • Germany • All rights reserved
8012664/XB29/2013-06-11
Subject to change without notice
Fieldbus gateways
Life guarding
Life guarding is performed by the gateway itself. The node life time is calculated in the
gateway from the values of SDO 100C (guard time) and SDO 100D (life time factor). If the
gateway does not receive a node guarding message at least once within this node life time
from an NMT master, the gateway generates an internal “cable break” error that can be
processed by the CPU main module and the NS LED will start flashing
Red.
Cable break detection is possible for the gateway either if life guarding is activated, i.e.
if both objects SDO 100C and SDO 100D have a value other than 0. In this case life
guarding starts when the first node guarding request is received from an NMT master
and ends if the master sends a “Reset communication”.
Alternatively, cable break detection is possible if the gateway is configured as a heart-
beat consumer. In this case, the cable break detection is performed by the gateway
itself.
Heartbeat (producer) works without node guarding. In this case, the gateway can not
detect a fieldbus cable break.
Heartbeat and node guarding/life guarding can not be used simultaneously.
If the configuration is changed from activated life guarding to no life guarding or vice
versa a complete power reset of the Flexi Soft system is required to setup the CANopen
network communication properly.
The following table gives an overview of the supported guarding protocols depending on
the configuration of SDO 1016 and SDO 1017 (heartbeat), SDO 100C (guard time) and
SDO 100D (life time factor).
SDO
1016
SDO
1017
SDO
100C ×
100D
Gateway heartbeat
Gateway
life guarding
NMT master
node guarding
0
0
0
Not allowed: Always use either node guarding or heartbeat!
0
0
> 0
Deactivated
Cable break
detection
Required
> 0
0
0
Cyclic heartbeat
(consumer)
Cable break
detection
Possible for other
slaves
0
> 0
0
Cyclic heartbeat
(producer)
Not possible
Not possible, but
guarding as heart-
beat consumer is
possible
> 0
> 0
0
Cyclic heartbeat
(producer and
consumer)
Cable break
detection
Not possible
> 0
> 0
> 0
Not allowed
It is not useful to use heartbeat and life guarding at the same time.
Notes
Tab. 129: Guarding protocol
overview and comparison
Note