Micromod MOD: 30MLTraining Manual - Manual (Page 179)

12 Sequence Lab
12.1 Foreword
Configuring a sequence, logic or batch application is easier than ever with ViZapp. You
can configure names for the inputs, outputs and steps in a sequence block and they will be
reflected in the connections and debug screen. Unlike a PLC, the user is not required to
keep track of database or memory locations, and the use of step names instead of numbers
in the logic makes adding, moving or deleting steps much less engineering-intensive.
12.2 Objectives
This lab is designed to show some of the power of the Sequence Block. We will configure
a very simple sequence that includes starting a batch, filling a tank, heating the contents
and maintaining them at a certain temperature for a certain time, cooling them down and
draining the tank.

NOTE: Because this lab is for demonstration purposes, it does NOT contain all the
logic elements that would be required for a real application.
The basic P&ID for this demo looks like this:
Figure 12 .1.
Sample Batch
Reactor
TE
LSH
LSL
The operator starts the sequence from the front panel of the controller (configured in a
later lab). If the drain valve is closed, the charge valve opens and the vessel begins to fill.
When the level reaches a certain point, a high level switch is tripped and the Charge valve
shuts. A setpoint of 90 degrees is sent to a temperature controller (also part of a later lab)
and begins heating the product.
When the product temperature reaches setpoint, it is held there for one hour, then allowed
to cool to 20 degrees (a setpoint of 20 is sent to the same temperature controller).
12 - 1