Programming instructions

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A quick calculation shows that the longest time duration that can be handled by a
timer is (32,767 x .1 sec / 60) = 54.36 minutes. What happens if it is necessary
to run a timer longer than this? The answer uses a combination of timers and
counters together like the program below:
T0 runs for 1 minute. After 1 minute, T0 causes C0 to increment. After 60
increments, or 1 hour, C1 increments. After 24 hours C1 would go true and set a
day counter.
Note: The program shown above is not complete. What needs to be added to
make it work properly?
12.4 Additional Timer Commands
There are some other handy timer instructions within the FX Series command
set. These are a teaching timer and an hour meter command.
The TTMR command measures the amount of time in seconds which its input
condition is on. It amplifies this value based on a magnification setting and
stores this value in a data register. Once in the data register, it can be used as a
preset to another timer instruction or in any word commands.
The magnification takes the number of seconds and multiples it by 10
N
, where n
is 0, 1, or 2. To store the actual number of seconds, the magnification will be K0.
To make a preset for a 100msec timer, you would enter K1 in the magnification
parameter. This will take the number of seconds and multiply it by 10 to get the
number of 100msec increments. For a 10msec timer, the number of seconds
would need to be multiplied by 100, or 10
2
. The magnification would be K2.