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4-18 Micro PLC Programmer’s Guide – April 1994 GFK-0804B
Off Timer
The Off Timer turns OFF an output after a specified time period. The time period can be
from 0 to 6553.5 seconds. However, if a constant is used for the Preset value, the time
period can be from 0 to 3276.7 seconds.
To program a timer function, enter two inputs (in the example below, I1, and I2), and
two parameters (R1 and R385 in the example). In this example, the timer length is not
specified directly. Instead, this example uses the register R385 as the second parameter.
In this case, register R385 contains the value 100. The timer length can be placed in that
register either by program logic or from the Hand-held Progammer or programming
software.
When the program encounters a register location as the second parameter of the timer, it
looks in that register for the value it contains, and uses that value as the timer length. So
for this example, timing is the same as for the previous example.
The current timer value (in R1 above) will not increment beyond its programmed length
(time period), even if I1 remains closed and I2 remains open.
Programming Software Instructions
If you are using the programming software, refer to the instructions on page 4-16.
Example and HHP Instructions
Ladder Diagram Hand-held Programmer
Timing Diagram When I1 is 1, the timer is started. The
timer setting is:
100 x 0.1 = 10 Sec.
During the operation of the timer, if I1
switches to 0, the timer is on hold. When
I1 is 1 again, the timer resumes timing,
When the timer reaches the set value (10
seconds), output coil C1 deactivates.
Input I2 is used to reset the timer. When
both I1 and I2 are ON, the timer remains
reset.
I1 C1 START
START
TIMER
OUT
F1
I1
I2
R1
R385
C1
Input I1
Register R1
Coil C1
I2
R1
OFTMR
R385
100
0
Input I2
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