[TRNSYS-users] Type 936

[thornton at tess-inc.com]

On 2022-11-23 05:23, Ana Delgado via TRNSYS-users wrote:

> Moreover, I want to put a safety measure in the code that does not let
> the temperature inside be higher than -9ºC, and it should turn on the
> compressor without the input commands. However, I am facing the
> difficulty of the code turning on and off the compressor immediately.
> The temperature switches between -8.1ºC and -8ºC. Does anyone here
> work with type 936 and can help me?

Ana - as the author of that model I'd be happy to help you.  Have you 
considered having your input control signal be the maximum of the two 
concepts?  So the control signal is the maximum of your user-desired 
behavior and a control signal from a differential controller that's 
watching that critical -9 C temperature?

You could simply use an equation to combine the controls:

On_Refrigerator = MAX(UserControl,CriticalControl)

where UserControl is your current external control sequence and 
CriticalControl is a signal from a differential controller / thermostat 
that watches the refrigerator temperature and initiates the compressor 
when it gets too warm.  Then simply feed the On_Refrigerator signal to 
the model.

Jeff

-- 
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Jeff Thornton
President
Thermal Energy System Specialists (TESS)
3 N. Pinckney Street - Suite 202
Madison WI 53703
(608) 274-2577
www.tess-inc.com