Activating one output consecutively 2 times in ladder diagram
- Thread starter lekxa8
- Start date
Steve Bailey
Lifetime Supporting Member + Moderator
How much time between consecutive activations?
Do you want:
On 100 mS
Off x ms
On 100 ms
Stop
Or:
On 100 mS
Off x ms
On 100 ms
Off x ms
On 100 ms
Off x ms
On 100 ms
Off x ms
On 100 ms
...
ad infinitum?
Do you want:
On 100 mS
Off x ms
On 100 ms
Stop
Or:
On 100 mS
Off x ms
On 100 ms
Off x ms
On 100 ms
Off x ms
On 100 ms
Off x ms
On 100 ms
...
ad infinitum?
Steve Bailey
Lifetime Supporting Member + Moderator
You can do it with two timers, one controlling the on time, the other controlling the off time.
You can do it with a single timer with a preset of 120 ms, turning the output on while the accumulated value is 100 ms or less and off while the accumulated value is greater than 100 ms, and resetting the timer when the accumulated value reaches the preset.
You can do it with a single timer with a preset of 120 ms, turning the output on while the accumulated value is 100 ms or less and off while the accumulated value is greater than 100 ms, and resetting the timer when the accumulated value reaches the preset.
drbitboy
Lifetime Supporting Member
(edit: this is close to the same as @Steve Bailey's second suggestion)
Run a single TON with a 220ms preset.
The output is 1 when
- the timer is enabled AND
- (the current value of the timer is less than 100 OR greater than 119) AND
- the timer is not done
Run a single TON with a 220ms preset.
The output is 1 when
- the timer is enabled AND
- (the current value of the timer is less than 100 OR greater than 119) AND
- the timer is not done
Last edited:
OK, I know this is the place where you can get free solution for your homework assignment. Now that you have some hints, please provide us what you tried so far at least.
Another hint from me, is to try the new AI and see what it can come up with.
Another hint from me, is to try the new AI and see what it can come up with.
drbitboy
Lifetime Supporting Member
On Allen-Bradley TONs, you can seal in the timer with the timer object's .TT bit, so the TON will run but once
A simpler option might be a TOF, if it's okay to start the first pulse on the falling edge of the start bit (assuming there is a start bit).
A simpler option might be a TOF, if it's okay to start the first pulse on the falling edge of the start bit (assuming there is a start bit).
drbitboy
Lifetime Supporting Member
When is the assignment due?
BachPhi
Member
I am sorry , L33ER! I want to try it first. so here is the result from my AI:
Here is a ladder logic that can turn on an output for 100ms, then off for 20ms, then turn it back on for 100ms:
| |---[ ]---|/|---( )---|
| | T1 | | O1 |
| | | | |
| |---[ ]---| | |
| | T2 | | |
In this ladder logic diagram, T1 is a timer that turns on for 100ms and T2 is a timer that turns off for 20ms. O1 is the output that is controlled by the timers. When T1 is on, O1 is turned on. When T2 is on, O1 is turned off.
Here is a ladder logic that can turn on an output for 100ms, then off for 20ms, then turn it back on for 100ms:
| |---[ ]---|/|---( )---|
| | T1 | | O1 |
| | | | |
| |---[ ]---| | |
| | T2 | | |
In this ladder logic diagram, T1 is a timer that turns on for 100ms and T2 is a timer that turns off for 20ms. O1 is the output that is controlled by the timers. When T1 is on, O1 is turned on. When T2 is on, O1 is turned off.
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