is typical that the design is not comprehensive.
It is installed on the motor valve, the run time is 5 seconds across the "close"-position to "open"- position and vice-versa.
We have a need to drive this valve to certain position.
It is installed on the motor valve, the run time is 5 seconds across the "close"-position to "open"- position and vice-versa.
We have a need to drive this valve to certain position.
how can I manage it? in S7/300 logic?
We do not have the cool program-blocks for the purpose,
We do not have the cool program-blocks for the purpose,
But, plc, has a clock- pulses, so program compares the position of measuring the difference from the regulation high.
When a decision is made, I use and-block with clock-pulse (e.g. 2 second section time, then the engine does not drive over to the desired position.
But that was no good.. proble is, that position measurement was quite slow.
Better solution; I use 0,5 sec pulses AND 1 second pulses to drive motor.
What happens then? Driving is pulsating, but at least the goal is achieved, not the case vibrations. However, this is not good for relays and motor. It would be better to change the slower of the device.
Of cource, better idea is to use caltulated driving time, but it is too
When a decision is made, I use and-block with clock-pulse (e.g. 2 second section time, then the engine does not drive over to the desired position.
But that was no good.. proble is, that position measurement was quite slow.
Better solution; I use 0,5 sec pulses AND 1 second pulses to drive motor.
What happens then? Driving is pulsating, but at least the goal is achieved, not the case vibrations. However, this is not good for relays and motor. It would be better to change the slower of the device.
Of cource, better idea is to use caltulated driving time, but it is too
laborious to do in this PLC.
The problem is that automation is expected to also be of crucial design errors
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