Analog input to analog Output on/off

[kikitron]

Hi,

 

A have one question. I control analog output 0-10V with potentiometer on analog input 4-20mA.

Is it possible to add a switch that I first set the value by potentiometer and when I press switch ON panel I get seted vaule on analog output ?

Now is working directly when i move potentiometer a got value 0-10V on analog output.

AI-O_test.vlp

[Flex727]

Yes, add a line after your linearization blocks, as follows, should do it:

[kikitron]

Perfect thanke you its working

Is it possible to do it through the panel to if I add a button on display ?

[Flex727]

Yes, just substitute an MB for the I 0 in the example above. Then link the MB to a button on the HMI. You can use either a regular pushbutton for momentary contact, or use a Binary Switch with the Toggle function checked.

[kikitron]

Thanke you @Flex727 for your help.

[kikitron]

I have another question:

Is it possible to reset somehow all my MB buttons to state 0 when I turn on the PLC ?

Now If I push button I got 1 and if I switch off the PLC and switch it back on I still have 1. Now I would like to reset all my MBs somehow if I forgot to turn it down to 0.

[Joe Tauser]

Set the power-up value of each MB you want to set to 0 to "RESET".  It's the little plug icon next to the MB address.

Joe T.  

[kikitron]

Perfect thanke you for fast answer and help 

[kikitron]

Another question about potentiometer.

To regulate analog output +/- 10V Im useing potentiometer 4,7kOhm + resistor on analog input (4...20mA).

Potentiometer scale is 0-10 (pic in attachment) and now I have problem that my 0V is on scale 8 and not 5.

Is it possible to calibrate somehow that my 0V will be in the midle (scale 5) ?

+/-10V is now working ok but my 0V is on scale 8 and I regulate 0..10V from scale 8...10 and 0V...-10V from scale 8-0.

 

[Flex727]

I'm not exactly sure what you're asking, but it seems like you could adjust your linearization blocks to achieve what you're wanting.

[kikitron]

I tryed with different values of linearization on analog input but with no luck. 

I would like that when I have potentiometer in the middle on scale 5 analog output needs to be 0V. Now 0V is on scale 8. I have less rotation adjustment from 0V to 10V (scale 8 to 10). And I have more rotation adjustment from 0V to -10V (scale 8 to 0).

Linearizarion is working ok only that 0V is not in the middle of the potentiometer.

[Flex727]

Add a fixed resister on your potentiometer.

[Flex727]

Regarding the linearization - go online with your PLC and record the MI values for your potentiometer at minimum and maximum position (0 & 10 positions). Now use that for the linearization block for your output. If you need help with that, then post those numbers here and I'll help you. As a sanity check, you should also record the number at position 5 to confirm that it's about halfway (in value) between 0 and 10 to confirm your potentiometer is linear.

[kikitron]

I have fixed resistor on potentiometer like on Picture below.

I calculate it 1082 Ohm to run from 4,07mA to 19,9mA on extension module IO-AI4-AO2 (analog input).

I recorder MI values:

0 = 835

5= 1390

10 = 4075

 

[Flex727]

It looks like you hit that pretty close. The IO-AI4-AO2 has 12-bit resolution, so you should see a value between 819 & 4095 on the 4-20mA input. Now add a linearization block that looks like this: