Rice Lake 720i Programmable Indicator/Controller - Installation Manual User Manual
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720i Installation Manual
Within the PCE, there are four temporary variables called user data. They are used as an interface between:
•
The steps and the database (such as reading or writing data)
•
The user and the database (such as searching by an ID)
•
The user and the step compares (such as setting a target value)
All data goes through these temporary variables as a “Get” or “Set.” A “Get” is used to get data from a user or from
a condition in a step. A “Set” is used to put data into a condition in a step.
Each variable supports a different type of data: integer (whole numbers without a decimal point); real (numbers
that can contain a decimal point); string (alphanumeric printable data); and datetime (preset format for the date and
time to be stored and printed). There is one location for each type of user data. The
User Clear
action will clear out
one of the four variables based on its type.
Performing a Merge
There are some checks to perform whenever merging is used because the editor assigns condition numbers to each
step:
1. Re-Check each step’s
Activate
and
Deactivate
to ensure they are still aimed at the correct step.
2. If any
Set
or
Get
Compare
actions are used, verify the condition number, as the editor will change it as it
builds a merged process.
3. If a
Step Compare
is used, verify the correct step is being evaluated.
Note
The above checks also apply if a step is moved up or down. If you move a step, ensure condition numbers are
updated accordingly.
Pause, Reset, and Restore Process
There are three unique actions that need a bit of clarification: the
Pause Process
,
Reset Process
, and
Restore Process
.
These actions are used to pause the process and then either restore (continue) or reset (abort) the process. These
actions are typically accomplished with a softkey or a digital input.
These actions will only affect the steps that have the
Pausable flag
set. Setting this flag in any of the actual process
steps means only those steps will be affected. When a
Pause Process
is initiated, only the pause actions for the
current step (or other enabled, pausable steps) are run. Those steps without the pausable flag set will still operate as
normal. For example, a free-running independent weight compare or any non-pausable, enabled step can continue
to activate/deactivate other non-pausable steps.
A
Pause
will stop the pausable steps. The state of each step is then saved. If a
Restore
is then executed, the steps’
states are restored and the process continues where it left off. If the
Reset
action is executed, all pausable steps go
back to the default state and the process will need to be manually restarted based on the setup of the process.
Along with the PCE Editor, there is also a Database Editor to build and download a database that can be used by
PCEE. First a Schema is built. This is the framework of the database. This will include the name, number of fields,
and the type of data each field will contain. This data can be used for displaying prompts, gathering data during a
batch process, and as a warehouse for any data that the PCE needs to use.
Use of the database is addressed using the database commands discussed later in this document.
Revolution
Whenever a PCE process is built, be sure to build a
Revolution III
hardware configuration file using the 720i
module so that all configuration parameters match the process. The
Revolution III
file will define any required
digital i/o, softkeys, and the print formats (AuxFmt) used.
In
Revolution III
, there is a Monitor Mode in the Tools tab of the editor, which can be used to set individual
parameters such as a DigOut to Output or Input.
Setting Up a Simple Three-Step Fill
The following example will set up three steps to start the process with DigIn 1, turn on DigOut 2 until the target is
reached (100 lbs), and wait for the scale to empty before allowing a restart.