Section 5

Section 5
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17
Example Program
Step 14:
Assigning a
Nickname to the
Preset Output
If you decide to assign a nickname to V2000, you will need to document that this
address will hold the preset for the timeout counter CT0 . Use a nickname that
describes the function. Move the cursor to highlight the OUT box for the V2000.
Select Tools from the upper menu bar. Next select the Documentation Editor or
press CTRL + D.
The dialog box shown below will appear. It will have V2000 in the box labeled
Element. Immediately to the right is the Nickname Box. Type in the nickname, in
this case use the name CT0 Preset.
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Example Program
After typing in the nickname information, Close the Documentation Editor when
you are finished.
Click on Close when finished.
The nickname will appear inside the OUT box above V2000. You are now ready to
create the second rung of ladder logic.
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Example Program
Step 15:
Adding an Internal
Relay to Start the
Timer
In this next rung youwill start a timer, have it timeout at a certain preset value, and
then reset itself. Choose to use C0 as the start relay; and of course, T0 is the timer
“done” bit for the TMR T0 timer.
Insert the “start relay” C0 first. Use a shortcut this time to create the normally
open contact on the rung. You may recall on the first rung, the normally open
contact icon was selected on the tool palette in order to create the contact. This
time, move the cursor to the point where the contact is to be placed and press
the F2 key. This opens the input box shown below and you can fill in the
information as before. The shortcut keys are much faster than the icon selection
method as you become more familiar with DirectSOFT.
Move the cursor to the
point of insertion.
Use F2 to bring up the
element dialog box.
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Example Program
Step 16:
Assigning a
Nickname to the
Start Contact
Next, document that C0 is the “start switch”. You could pull down the
Documentation Editor from Tools on the horizontal menu bar to enter this
information as a nickname. However, for learning purposes, use the hot key
equivalent–CTRL + D. This will bring up the Documentation Editor without having to
use the pull-down sub-menu of Tools.
If your cursor was on C0 when you used the CTRL + D combination, the browser
should have the C0 in the Element column. Type Start Switch in the Nickname
column.
Close the Documentation Editor, returning to the rung. The nickname should
be above the element C0.
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Example Program
Step 17:
Next, move the cursor further to the right on the rung to the point where you want to
Adding a Normally place the normally closed contact for the timer “done” bit (T0). Use shortcut key F3 to
bring up the dialog box for a normally closed contact. Type in T0. Finish by selecting
Closed Contact
the check mark.
Bring up the Documentation Editor again by using the CTRL + D combination.
Enter Ten Second Timer in the Nickname column. Close the Editor when
finished.
Step 18:
Adding a Nickname
to the Normally
Closed Contact
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Example Program
After the Documentation Editor closes, you will return to the rung where the
words Ten Second Timer will be above the normally closed T0 timeout relay.
Step 19:
Move the cursor to the end of the rung to enter the timer TMR T0. Since a timer is a
Inserting the Timer box command, you can use the shortcut key F7 to bring up the box instruction dialog
of the Instruction Browser. Once you have opened the dialog box shown below,
Instruction
move the cursor in the Box Class window to Timer/Counter/SR , move the cursor in
the Boxes window to TMR, and click on OK.
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Example Program
The element box shown below will appear. This is the element input window for the
timer. The first thing to do is allocate a particular timer. This example uses internal
timer TMR T0, therefore type in T0. The indicator light of the box should turn green to
tell you this is a valid entry. Notice also the nickname assigned earlier to the timeout
relay T0 appears above the first entry window. A second window also requires you fill
in a preset value for the timer. Use the Tab Key or click with the mouse to move to the
second field. The preset must be entered in tenths of a second. Therefore, K100
would be one hundred tenths of a second (100/10), or 10 seconds.
When you type in T0, the nickname
is automatically added.
Enter 10ths of a second
Click on the check mark to accept your entries. DirectSoft returns you to the rung
of ladder logic for further programming.
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