Using C-ACTIVITY-DESC in keyword expressions to assign LPD, equipment loads etc.

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The space description "C-ACTIVITY-DESC", as shown below, can be referenced by keyword expressions.

[cid:image003.png at 01CFAA5E.1E3325F0]

For example, to assign LPD by space type, follow these steps:

1. As always, save your project and work from a new copy whenever trying something that may be hard or impossible to undo if you pull an "oops".

2. Enter consistent space descriptions based on the first four characters of the description. ("Office - open" and "Office - Enclosed" will both be treated as "offi" because the BDL expression mechanism uses four characters.) This is the most time-consuming step.

3. Enter the following string as a User-Defined Default Expression for LIGHTING-W/AREA:

if(#RV(#L("LIGHTING-SCHEDUL",0))!=0) then unused

else switch(#L("C-ACTIVITY-DESC"))

case "acti": 0.8

case "clas": 1.4

case "offi": 1.0

default: 1.2

endswitch

endif

(Add or replace case statements, and the default value as applicable to your project's space types. I kept the DOE-2 default expression in the example above, and then added the switch statement.)

[cid:image008.png at 01CFAA5E.1E3325F0]

This appears in the input file as the following:

SET-DEFAULT FOR SPACE

LIGHTING-W/AREA = (

{if(#RV(#L("LIGHTING-SCHEDUL",0))!=0) then unused

else switch(#L("C-ACTIVITY-DESC"))

case "acti": 0.8

case "clas": 1.4

case "offi": 1.0

default: 1.2

endswitch

endif

} )

..

4. "Restore default" to the LIGHTING-W/AREA values of each space to apply the values from the keyword expression. You can do this manually by right-clicking in the field for each space or by deleting lines in the input file. I use the NoteTab Light text editor and the regular expression

"^ LIGHTING-W/AREA.*$" to delete all space LPD assignments (being careful not to delete the keyword expression just entered above), as follows:

[cid:image017.png at 01CFAA5E.1E3325F0]

5. Repeat these steps as desired for other keywords, such as EQUIPMENT-W/AREA, LIGHTING-SCHEDULE, AREA/PERSON etc. Be creative!

6. Do a happy dance.

H/T to Jeremy McClanathan for helping me with this previously.

Regards,
Bill

Bill Bishop's picture
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My vote is to simplify interior geometry as much as possible, as allowed by
App G. In our experience, having too many spaces / zones significantly
increases calculation time, complicates model editing, and makes eQUEST less
stable (i.e. increases likelihood of crashes). Arguably, breaking the actual
HVAC zones into separate spaces based on space type conflicts with App G
Table G3.1 #7 which says that ?
where HVAC zones are defined on HVAC design
drawings, each HVAC zone shall be modeled as a separate thermal block?.
eQUEST assumes that each space is an HVAC zone with its own thermostat / VAV
box, so modeling spaces within a zone may skew results compared to the model
that reflects the actual HVAC zoning.

You can still use expressions that Bill described below for zones with
homogeneous space types or with one predominant occupancy. For example, if
98% of zone area are corridors, and 2% are restrooms, using corridor LPD for
the entire zone in the baseline will have negligible impact on results. For
zones with diverse space types, we typically over-write the user default
(LPD based on activity type) with user expressions like the one below, for a
zone with 60% area taken by corridors, 10% by lobby, and 30% by storage.
(This expression replicates calculations done by eQUEST DD Wizard which
generates zone LPD based on inputs on screens 13 and 14 of the Shell
sequence.)

Maria

--

Maria Karpman LEED AP, BEMP

________________

Karpman Consulting

www.karpmanconsulting.net

Phone 860.430.1909

41C New London Turnpike

Glastonbury, CT 06033

Maria Karpman's picture
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Thanks Bill! I learned something today.

Vikram Sami
BEMP, LEED BD+C
Associate Partner

ZGF ARCHITECTS LLP
T 206.521.3509 E vikram.sami at zgf.com
925 Fourth Avenue, Suite 2400
Seattle, WA 98104

vsami's picture
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Joined: 2013-05-31
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Thanks Bill and Jeremy McClanathan
This is approach makes my day.
Thanks
Melissa

Melissa
Melissa Page Crowe's picture
Joined: 2011-09-30
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dear all,
i am very thankful for all of you, thank you indeed.

Wafik

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