Can we reference DESIGN-DAY inputs in zonal expressions?

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Hi friends!

Is fundamentally possible to, from within a user-expression, pull a value from cooling / heating DESIGN-DAY inputs?

In particular, I'd like to return DRYBULB-HIGH from both my cooling and heating DESIGN-DAY, using those values to inform zonal DESIGN-COOL-T and DESIGN-HEAT-T for unconditioned and plenum zones. I can see a path to have both DESIGN-DAY and zonal inputs reference a pair of global parameters, but I'm making every effort to minimize "#PA spam" in my regular model development.

~Nick

[cid:image001.png at 01D32641.AF583680]
Nick Caton, P.E., BEMP
Senior Energy Engineer
Regional Energy Engineering Manager
Energy and Sustainability Services
Schneider Electric

D 913.564.6361
M 785.410.3317
F 913.564.6380
E nicholas.caton at schneider-electric.com

15200 Santa Fe Trail Drive
Suite 204
Lenexa, KS 66219
United States

[cid:image002.png at 01D32641.AF583680]

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Hi Nick,
I haven't figured out a way to reference DESIGN-DAY keywords from outside of the command. The DESIGN-DAYs are not global parameters (so you can't use #G), and they do not have children that can reference them as parents. You could create global parameters per your own suggestion below.
An alternative is to reference other climate data inputs for your DESIGN-COOL-T and DESIGN-HEAT-T zone keywords.
For example, you could enter the monthly ground temperatures. Then, say you want the unconditioned zone DESIGN-HEAT-T to match the December ground temperature:
if(#RV(#G("SITE-PARAMETERS","GROUND-T",11))==0)
then #G("SITE-PARAMETERS","GROUND-T",11)
else 70 endif

Regards,
~Bill

William Bishop, PE, BEMP, BEAP, CEM, LEED AP | Pathfinder Engineers & Architects LLP
Senior Energy Engineer

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Isn't it funny, I thought DESIGN-DAYs should be accessible via #G() initially as well!

I'm a little averse to making my ground temps equal to winter/summer design DB conditions as a general practice... A more innocuous option for leveraging a SITE-PARAMETER as a proxy/container might be LONGITUDE... but ideally I'm looking for a pair of "containers" and I think LATITUDE is actually leveraged for solar sky model stuff (daylight calculations, possibly cooling DESIGN-DAY but I have my doubts)...

Outside of SITE-PARAMETERs... Have I perhaps stumbled upon the exact intent/purpose behind these "Variable##" "containters" under the PROJECT-DATA variables? Does anyone know how to access these values via keyword expresssions?
[cid:image004.png at 01D327F7.448C3100]

~Nick

[cid:image001.png at 01D327F5.475CA100]
Nick Caton, P.E., BEMP
Senior Energy Engineer
Regional Energy Engineering Manager
Energy and Sustainability Services
Schneider Electric

D 913.564.6361
M 785.410.3317
F 913.564.6380
E nicholas.caton at schneider-electric.com

15200 Santa Fe Trail Drive
Suite 204
Lenexa, KS 66219
United States

[cid:image002.png at 01D327F5.475CA100]

via Equest-users's picture
Joined: 2016-07-15
Reputation: 200

Ooh, I got it!

If you enter this:
[cid:image002.png at 01D327F8.1DE584B0]
... which by the way looks like this in the INP:
[cid:image001.png at 01D327F8.5E8E67C0]

Then this
#G("PROJECT-DATA","Variable01")

Returns 56!

... So here's a way on paper to store up to 20 variables for building model input automation purposes without cluttering up the #PA list! Nice!

~Nick

[cid:image003.png at 01D327F8.1DE584B0]
Nick Caton, P.E., BEMP
Senior Energy Engineer
Regional Energy Engineering Manager
Energy and Sustainability Services
Schneider Electric

D 913.564.6361
M 785.410.3317
F 913.564.6380
E nicholas.caton at schneider-electric.com

15200 Santa Fe Trail Drive
Suite 204
Lenexa, KS 66219
United States

[cid:image005.png at 01D327F8.1DE584B0]

via Equest-users's picture
Joined: 2016-07-15
Reputation: 200