Hello!
I read on MacroFloOpeningTypes.pdf this formula to control a window by the Degree of Opening: int(100*(ta/24)).
I'd like to know what this formula means, ie, why is there a command to integrate the values of ta?
Thanks for the attention.
Windows Control
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Complex Potential
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Re: Windows Control
Hiya
I cannot find that pdf.
The int(x) function does not integrate but rather returns an Integer value of x, rounded towards zero.
With that in mind, the formula you have quoted looks quite wrong to my eyes since a modulating profile can only vary between 0 and 1 and that formula could potentially be returning values in excess of 100 when ta is greater than 24.
I suspect this formulae is trying to proportionally vary the opening of the window based on how close the internal temperature gets to 24C but the gt() function would be a better method of achieving this.
If you can explain exactly what you want the windows to do, we can help you with the formula.
CP
I cannot find that pdf.
The int(x) function does not integrate but rather returns an Integer value of x, rounded towards zero.
With that in mind, the formula you have quoted looks quite wrong to my eyes since a modulating profile can only vary between 0 and 1 and that formula could potentially be returning values in excess of 100 when ta is greater than 24.
I suspect this formulae is trying to proportionally vary the opening of the window based on how close the internal temperature gets to 24C but the gt() function would be a better method of achieving this.
If you can explain exactly what you want the windows to do, we can help you with the formula.
CP
Re: Windows Control
Current version of that manual has that part removed, it did have an explanation below it
There are other ways to do this, I hadn't seen that one before but as a demonstration of how to use a formula profile rather than being limited to the threshold temp in the opening types interface I would say it's useful.
Most up to date guides are always available form our website http://www.iesve.com/support/userguides
Phil
It was obviously removed for a reason (wasn't me this time) but if you take out the 100 then I'd say it looks reasonable and gives a method of opening and closing the window based on that threshold temperature while also attempting to make it proportional to how warm the room is.This opens the windows when the room air temperature exceeds 24°C and (unlike the Temperature Threshold control) closes them immediately it falls below this value. The formula should be assigned to the appropriate daily profile for the period of the day when the windows might be opened. If this type of window opening control is used, the Opening Threshold temperature should be disabled by setting it to a low value such as 0°C.
See the section headed Formula Profiles in the APpro User Guide for further guidance on the use of formula profiles.
There are other ways to do this, I hadn't seen that one before but as a demonstration of how to use a formula profile rather than being limited to the threshold temp in the opening types interface I would say it's useful.
Most up to date guides are always available form our website http://www.iesve.com/support/userguides
Phil
IES Worldwide Technical Support