motor control

Hello ols,

I think that should be possible. Following questions to that:
How do your input signals look exactly? How many channels 1 or 2 (A and B)? In which range of the frequency do the input signals lie?

Which output signals do you need for the excitation of the frequency inverter? Do you need digital or analog output signals?
Which functions are supposed to join your input signals with the exits? Which reports and/or display values do you need?

Best regards
Betel

Hello !
I was thinking of using a 2 channel encoder with good resolution 250 ppr,but then the counter does not count very high,and how to evaluate the counter signal?
The frequency inverter uses only digital inputs and is not my problem,the counter is.
maybe i will use prox,switch and 10 ppr 1 channel but still don´t understand how to use counter output to positioning,any ideas??

Hello ola,

unfortunately has the LOGO! no such a function to the (cycle time independent) evaluation of incremental indicators with 2 channels (A and B). Therefore also I had asked the question "How is onto the forum an evaluation of the signals "A" and "B" of synchros possible"?. Meanwhile I have in the German part of the forum in the contribution

"Wie ist eine Auswertung der Signale "A" und "B" von Drehgebern möglich ?"
/tf/WW/de/Posts/8227

concepts to solution and circuits published. These had the directional impulse count in the case of maximum information recovery (evaluation / flank evaluation = 4x) to the destination.

ALL circuit-technical solutions lead, in particular because of the analysis of the direction, to restrictions the maximally permissible signal input frequency fab! This follows the current smallest fz cycle frequency in the case of most favorable circuit arrangement the LOGO! The highest signal frequency (= fz/2) is possible in the case of simple evaluation (with counters, above in the circuits represented). The complete information of the signals A and B i want to solve on the other hand, then the maximum signal frequency is restricted to fab = fz/8 (very below in the circuit diagram). In the middle of the circuits one (in each case more different) is available to circuit for the simulated generation of signals. Forum_Inkrementalgeber_V03.zip

Your information let to presume that you are rather interested instead of an impulse count for the rotational position sensing onto an evaluation of the impulses per unit of time (= speed measurement), however. The block "threshold trigger" is for this purpose but it is not easy and in most cases not possible to scal the results in physical units. Therefore I published a more flexible copy as an circuit in the forum, for example under

Display of scaled High Speed Input Values
/tf/WW/en/Posts/13144

In the file appendix I created for you now a modified andbuild an circuit design adapted to an incremental 2 cannal sensor... I hope you manage that, otherwise I want to pay attention to your questions here.

How does the circuit work?
B110 defines the measuring time (as G_T). B003 and B007 store the measured value preceding in each case (= number of the impulses per measuring time). The amplifers B005 and B008 calculate the scaled value. B001 multiplies this value with -1 (for the other direction). The directional final result gets B012 then.

The impulses of the channel A are added in the counter during the measuring time. This keeps up the maximum rate of 2 kHz occur! With the aid of the analoge amplifers the counter value is converted into a physical unit.

The definition of the direction can occur on the other hand only at a signal frequency of maximally fz/2 (through analysis of A and B). I chose 50 Hz as a boundary, what is achieved with B011. With higher frequencies of the two coupled input signals the up to now recognized direction is stored and reused up to the drop of the signal frequency! This procedure should function in the case of motor logics perfectly because a route reversal is always accompanied by a preceding rate decrease should go around.

In the contribution listed above also references to a signal frequency division are by means of external circuits indicated (Attachment: 173754-da-01-en-C-MOS-IC_HEF4526B.zip).

Complementing for this purpose the sensor signals A and B can be provided also with IC´s (Data sheet LS7083_LS7084.pdf) externally converted into pulses and a direction signal and where appropriate through an impulse division above C-MOS-IC_HEF4526B the LOGO. In the LOGO! a fabrication with simple counter, digital threshold trigger or my circuit "threshold trigger", however, still modified to the display of the sense of rotation (solvedly in analog mode to the circuit in the file appendix), occurs then.

Best regards
Betel