Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) Algorithms, Tables and Sequential Logic Functions - Manual (Page 154)

Logic Functions - Book 2
CONFIGURING THE SEQUENCE BLOCK
11-8
Table 11-6. Step, Output and Transition Logic Definition Procedure
Step Procedure Comments
1 On the SEQ properties display, select the Steps menu.
2 Select Add and type the Step name Idle.
3 Enter the transition expression
IF LevelLO && !Draining THEN Fill
This is the expression required to
control the change from Idle (Step 1)
to Fill (Step 2). It means that if the
digital input StartPB is true, and the
digital input Draining is not true, then
go to the Fill Step. The ELSE portion
of this statement is implied as else do
nothing.
The expressions are not case
sensitive and no punctuation is used.
The spacing must be entered exactly
as shown. There is a space between
each word, no space in the logical
AND (&&) operator, and no space
after the logical not(!) operator.
4 Modify the output data for the idle step as defined in
Table 11-5 Step 1.
5 Using the procedure of Steps 2 through 4, define the
expressions for sequence steps 2 through 6 as follows:
Step 2 Fill, type:
If LevelHi then Heat
Step 3 Heat, type:
If Temp == HeatSP then Cook
Step 4 Cook, type:
If Time >= 1:00:00.000 then Cool
Step 5 Cool, type:
If Temp == CoolSP then Drain
Step 6 Drain, type:
If LevelLO then Idle
The attribute NEXT (Next Step) can
be used in the expression instead of
the step name when the required
transition is to the next step in the
sequence.
There is no space in the equals (==)
and greater-than-or-equal (>=)
operators.
When time is used in an expression,
the >= operator must be used
because the time data may not be
scanned when its value is precisely
equal to the configured value.
6 Select OK to close the block. This action completes the
configuration of the Sequence Block.
The remaining configuration
requirements for this application
example are:
•
Defining the I/O Modules
•
Connecting the I/O Modules
•
Compiling the data base