In this article, an emergency stop is modeled using two methods. In the first method, the emergency stop is monitored as a zone and in the second, the emergency stop is modeled as a CMZ.
An emergency stop can be modeled in different ways. To be able to start, the emergency stop must be inactive.
Logic layer:
There are two different ways of defining the emergency stop in the system layer.
Option 1:
Here, the emergency stop is created as a Zone In. An I - Interlock Check is set in each step of the inverted zone. The sequence now constantly monitors whether the emergency stop is not active.
System layer:
Option 2:
An emergency stop can be modeled as a CMZ or TCMZ. The CMZ - Constantly Monitored Zone refers to the entire system, a hardware zone or a sequence in a machine that is constantly monitored by sensors or other monitoring mechanisms. In this case, the input is automatically monitored in each step and the automatic process is stopped. The "Inverted" option must be activated for this. A reset is required after troubleshooting.
