[TRNSYS-users] "if" function in trnsys

[Jeff Thornton via TRNSYS-users]

Y_Diverter = 0.5*GE(buffertanktoptemp,60)
+ 0.5*GE(buffertanktoptemp,60)*GE(TEStoptemp,60)

Be aware that if your temperatures change quickly, you'll likely run into convergence problems with this approach.  An even better approach is to replace the GE functions in that equation with the signals from an aquastat controller.  The aquastats have some hysteresis built in to avoid issues like this (On at 62 and off at 58 for example).  There are aquastats in the TESS Libraries but you also use the Type 2 differential controller if you don't have the extended library package.


Jeff

Sent from my iPhone

> On Apr 21, 2017, at 12:53 AM, Rm Chemilo via TRNSYS-users <trnsys-users at lists.onebuilding.org> wrote:
> 
> Dear all
> 
> I want to know is there any way to apply this excel function below in trnsys. I want to use this function to control the diverter for my system
> 
> =IF(AND(buffertanktoptemp>60,TEStoptemp>60),0.5,IF(buffertanktoptemp>=60,1,0))
> 
> Actually I have tried to use GT and LT statement but it doesn't seem to work properly as I want. Can anybody help me?
> 
> Thanks
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