
X20(c)SC2212
22
Data sheet V1.141 X20(c)SC2212 Translation of the original documentation
Disable OSSD = No
Disable OSSD = Yes-ATTENTION
Error on output
Error / module
Switched off
Switched on
Switched off
Switched on
Short circuit between SOx+ (output type A) and SOx- (output type A)
X20SC0xxx
X20SLXxxx
X20SRTxxx
X20SOx1x0
Not detected
Detected
Not detected
Detected
Table 13: SO error detection
1)
If SOx is shorted to high potentials, this will be detected by the module, but the connected actuator cannot be cut off due to the "only-plus-switching" design
of the channel.
2)
Open circuit can be detected via signal "CurrentOK". However, this signal cannot be used for safety purposes.
Danger!
With "Disable OSSD = Yes-ATTENTION", the module has reduced error detection capabilities and no
longer meets the requirements for SIL 3 per EN 62061:2013 or PL e per EN ISO 13849-1:2015.
In order to meet the requirements for applications up to SIL 2 per EN 62061:2013 or PL d per
EN ISO 13849-1:2015, the user must check the safety function on a daily basis when using type B
output channels.
For type B2 output channels, it is also important to ensure that all of the module's output channels are
simultaneously in a switched-off state for at least 1 s during this test.
On X20SRTxxx modules, each output channel being used must be checked before the first safety
request and every 24 hours. For this check, the corresponding channel must be switched on and off
at least once.
Danger!
Possible error behavior of the actuators must be analyzed and avoided using corresponding responses
(positively driven read-back contacts on a contactor, pressure switch on valves, etc.).
Danger!
This danger warning applies to all the modules listed in the "SO error detection" table with the excep-
tion of output channels of type A!
If SOx is shorted to high potentials, this will be detected by the module, but the connected actuator
cannot be cut off due to the "only-plus-switching" design of the channel. Make sure that the wiring
is correct in order to rule out SOx short circuits to high potentials (see EN ISO 13849-2:2012, Annex
D.2.4, Table D.4).