schmersal PSC1 Series Installation Manual page 72

Installation manual
4.3.4.2.3 Single-channel switching relay or semiconductor output with dual-channel external
circuit with testing
For safety applications from PL c according to EN ISO 13849-1 it is recommended or required to
operate two external shutdown elements. In addition, a device for testing the complete chain and a
signaling/warning device on the detection of a fault are required to achieve PL c or higher – see
comments in 4.3.4.2.2.
X21
Q0_P
Q1_N
Q2_P
Q3_N
X12
I12
I13
T0
T1
X13
NC
NC
Y0
Y1
L +
L -
Single-channel switching output Q0_P with dual-channel external circuit and monitoring on input 12 as collective feedback
The two external monitoring contacts are connected in series, supplied with pulse signal T0 and read
via input 12. Input 12 was used as the readback input, however it is also possible to use any another
input.
PSC1-C-10 Installation manual V2.7
Version: 57E
Page 72 of 174