36
2TLC172001M0211_A
Output examples 2:
Contact expansion with expansion relays and safety relay
The examples give the same degree of safety and have the same advantages and
disadvantages as output examples 1 and can be used for the same type of applications.
Output examples 3:
Short circuit protected
Connection and monitoring of contactors with protection against short circuit, for applications
with very high demands on safety integrity level. (Category 4). In the example using output Q2
the conductor is protected with a shield connected to protective ground. Examples are
applications for safeguarding the operator of manual operated machines like presses and press
brakes.
B
Q1
A
0V
Q2
B
A
Monitoring
0V
/IQ_
+24
I_/IQ_
I_/IQ_
Monitoring
/IQ_
+24
+24V
+24V
B
A
Q0
-24V
(Minus)
InA
Test
InB
B
B
Q0
A
Q3
A
/IQ_
+24
0V
I_/IQ_
0V
I_/IQ_
Q2
+24
/IQ_
(+)
(-)
(+)
(-)
A
B
Monitoring
Monitoring
Q1
A
B
U
I_/IQ_
Q2
(+)
(-)
(+)
(-)
/IQ_
+24
B
A
Monitoring
