schmersal PSC1-C-10 Series Installation Manual page 78

Installation manual
4.3.5.2.2 Single-channel circuit with testing
On the usage of a dual-channel output (IQQx) in conjunction with an external single-channel circuit
with testing. In particular, positively driven auxiliary contacts are required for electromechanical
devices, or valve position signal contacts are required for this purpose for hydraulic or pneumatic
components. A signaling/warning device for the indication of the failure is required. The
signaling/warning device must immediately make clear the hazardous situation to the operator.
The achievable PL is heavily dependent on the test rate, a maximum of PL d according to EN ISO
13849-1 can be achieved!
X21
IQQ02
IQQ03
IQQ04
IQQ05
X12
IQI00
IQQ01
T0
T1
X13
NC
NC
Y0
Y1
L +
L -
Dual-channel output with single-channel circuit with testing
Safety instructions:
•
Only recommended to a limited extent for safety applications! On this topic see also the
information in EN ISO 13849-1 on usage and the fault exclusions necessary.
•
For Category 2 a test rate > 100 * demand rate is required
Alternatively, testing of the safety function can now also be carried out immediately upon
request, if the total time required to detect the failure and to transfer the machine to a safe
state (usually the machine is stopped) is shorter than the time required to reach the hazard.
•
If a hazardous situation is detected during a test of the safety function, suitable control
measures must be initiated. A safe state must be initiated for PL d, which must not be canceled
until the error has been eliminated. For PL up to and including PL c, it is also possible to use a
warning or signaling device to indicate an error if a safe state cannot be initiated.
PSC1-C-10 Installation manual V2.6
Version: 57E
Page 78 of 173