time regulated temp adjust

[tester2]

Hello.

I have asked this question before and i got some few good tips.

What im after is follow.

I whant to set a setpoint in the hmi, let say 28celsius.

this setpoint is going to increase 4celsius to 24celisus between clock 22.00 and 08.00 evry day.

and after 08.00 it should go back up to 28celsius.

i have today manage to do this with a big ladder. but i belive this can be easyer.

Can someone give me a tip or an example how to this with MF or any other options.

best regards

kaare

[Emil]

Hi Tester 2,

Let me understand:

Do you want just to set two different setpoints - with mentioned RTC change, or you want the temperature - to rise, for example from 24C at 22:00 to 28C at 8:00 and then once again to change slownly with the time.

In first case - it's very simple!

You need ot use Clock function - Hour. You need to set hours for 24C and hours for 28C. There will be two MB - one for each range. Let's say - MB0 will be active between 8:00 and 22:00, and MB1 - between 22:00 and 8:00.

With positive transition of each bit you will store the relevant setpoint to MI, which is related to temperature controller.

Described logic will take 4 very simple nets.

Is this helpful?

[tester2]

Hi Tester 2,

Let me understand:

Do you want just to set two different setpoints - with mentioned RTC change, or you want the temperature - to rise, for example from 24C at 22:00 to 28C at 8:00 and then once again to change slownly with the time.

In first case - it's very simple!

You need ot use Clock function - Hour. You need to set hours for 24C and hours for 28C. There will be two MB - one for each range. Let's say - MB0 will be active between 8:00 and 22:00, and MB1 - between 22:00 and 8:00.

With positive transition of each bit you will store the relevant setpoint to MI, which is related to temperature controller.

Described logic will take 4 very simple nets.

Is this helpful?

hello Emil

tnx for a nice tip. i will take this with me.

im using this temperature controll to set the room temp in a house.

This is the option i want in my control.

from HMI im interested to set room temp setpoint. ie 28Celisus.

from hmi i allso whant to have an option to change the clock for when i wont to increase the temp.

Lets say i whant to set the from 22.00 to 08.00.

im allso interested to set the value in hmi let say 4celisus the temp should increase in that timeframe.

this is what i would like to have an example for.

[tester2]

Hi Tester 2,

Let me understand:

Do you want just to set two different setpoints - with mentioned RTC change, or you want the temperature - to rise, for example from 24C at 22:00 to 28C at 8:00 and then once again to change slownly with the time.

In first case - it's very simple!

You need ot use Clock function - Hour. You need to set hours for 24C and hours for 28C. There will be two MB - one for each range. Let's say - MB0 will be active between 8:00 and 22:00, and MB1 - between 22:00 and 8:00.

With positive transition of each bit you will store the relevant setpoint to MI, which is related to temperature controller.

Described logic will take 4 very simple nets.

Is this helpful?

here is an picture for the recent post

[Emil]

Hi Tester 2,

From your picture, I saw you found already the right way - using indirect clock (instead of direct in my example) and MI to keep the temperature instead of constant number.

Is there anything else which remains open and I can help you with?

[tester2]

Hi Tester 2,

From your picture, I saw you found already the right way - using indirect clock (instead of direct in my example) and MI to keep the temperature instead of constant number.

Is there anything else which remains open and I can help you with?

Hello Emil.

I have made an example of what im after.

if you can look at it and maybe come with tips to make it better/easyer.

i`m interested in see other solutions to reach the same result.

this is becouse im a newbe on this and willing to learn other soultions.

Br

Kaare

night.vlp

[Emil]

Hi Tester 2,

The logic you did is right. It's also qute simple. I hope you agree with me.

Few small notes:

1. First of all - you need to write one rung per net. In your case the program needs to be divided in 3 nets. There are few good reasons to do this. Please check VisiLogic Help topic "Ladder Net" for details.

2. In your last rung, use Negative transition contact of MB0 to perform the calculation only once - when it reach the right hour - not each scan. You can find -|N|- contact in Boolena menu > Contacts.

3. In rung 3, I'll just Store MI1 in MI4 (Store functions > Direct store). It's more elegant and will be executed faster by the controller.

4. Usually, when you connect temperature sensor direct to relevant AI of our controller, you receive reading direct in degrees, with resoluiton of 0.1 degree. I'll recommend both Setpoint (your MI1) and setpoint difference (MI0) to be in the same resuluiton.

I hope these small tips will be useful for you!

[tester2]

Hi Tester 2,

The logic you did is right. It's also qute simple. I hope you agree with me.

Few small notes:

1. First of all - you need to write one rung per net. In your case the program needs to be divided in 3 nets. There are few good reasons to do this. Please check VisiLogic Help topic "Ladder Net" for details.

2. In your last rung, use Negative transition contact of MB0 to perform the calculation only once - when it reach the right hour - not each scan. You can find -|N|- contact in Boolena menu > Contacts.

3. In rung 3, I'll just Store MI1 in MI4 (Store functions > Direct store). It's more elegant and will be executed faster by the controller.

4. Usually, when you connect temperature sensor direct to relevant AI of our controller, you receive reading direct in degrees, with resoluiton of 0.1 degree. I'll recommend both Setpoint (your MI1) and setpoint difference (MI0) to be in the same resuluiton.

I hope these small tips will be useful for you!

Hi Emil

thanks for your feedback.

Many good tips. as allways very good support from unitronics. :-)