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### Thermochromic IDF Example Explanation

Does anyone know why the idf example both in the Input Output Reference and the idf example file use different glazing materials all with the exact same properties for WindowMaterial:GlazingGroup:Thermochromic? I believe the solar transmittance should be decreasing for higher temperatures. I have provided two of the materials for here for quick comparison, all twelve look the same to me though.

 Construction,
window_const,             !- Name
Usual Glass,              !- Layer 1
AIR 6MM,                  !- Layer 2
TCGlazings,               !- Layer 3
AIR 6MM,                  !- Layer 4
Usual Glass;              !- Layer 5

WindowMaterial:Gas,
AIR 6MM,                 !- Name
Air,                     !- Gas Type
0.0063;                  !- Thickness {m}

WindowMaterial:GlazingGroup:Thermochromic,
TCGlazings,
0 ,  TCGlazing0,
20,  TCGlazing20,
25,  TCGlazing25,
30,  TCGlazing30,
35,  TCGlazing35,
40,  TCGlazing40,
45,  TCGlazing45,
50,  TCGlazing50,
55,  TCGlazing55,
60,  TCGlazing60,
65,  TCGlazing65,
75,  TCGlazing75,
85,  TCGlazing85;

WindowMaterial:Glazing,
TCGlazing0,  !- Name
SpectralAverage,  !- Optical Data Type
,        !- Window Glass Spectral Data Set Name
0.0030,  !- Thickness
0.2442,  !- Solar Transmittance at Normal Incidence
0.7058,  !- Front Side Solar Reflectance at Normal Incidence
0.7058,  !- Back Side Solar Reflectance at Normal Incidence
0.3192,  !- Visible Transmittance at Normal Incidence
0.6308,  !- Front Side Visible Reflectance at Normal Incidence
0.6308,  !- Back Side Visible Reflectance at Normal Incidence
0.0000,  !- Infrared Transmittance at Normal Incidence
0.9000,  !- Front Side Infrared Hemispherical Emissivity
0.9000,  !- Back Side Infrared Hemispherical Emissivity
0.0199,  !- Conductivity
1.0000,  !- Dirt Correction Factor for Solar and Visible Transmittance
No;      !- Solar Diffusing

WindowMaterial:Glazing,
TCGlazing20,  !- Name
SpectralAverage,  !- Optical Data Type
,        !- Window Glass Spectral Data Set Name
0.0030,  !- Thickness
0.2442,  !- Solar Transmittance at Normal Incidence
0.7058,  !- Front Side Solar Reflectance at Normal Incidence
0.7058,  !- Back Side Solar Reflectance at Normal Incidence
0.3192,  !- Visible Transmittance at Normal Incidence
0.6308,  !- Front Side Visible Reflectance at Normal Incidence
0.6308,  !- Back Side Visible Reflectance at Normal Incidence
0.0000,  !- Infrared Transmittance at Normal Incidence
0.9000,  !- Front Side Infrared Hemispherical Emissivity
0.9000,  !- Back Side Infrared Hemispherical Emissivity
0.0199,  !- Conductivity
1.0000,  !- Dirt Correction Factor for Solar and Visible Transmittance
No;      !- Solar Diffusing


### Thermochromic IDF Example Explanation

Does anyone know why the idf example both in the Input Output Reference and the idf example file use different glazing materials all with the exact same properties for WindowMaterial:GlazingGroup:Thermochromic? I believe the solar transmittance should be decreasing for higher temperatures. I have provided two of the materials for here for quick comparison, all twelve look the same to me though.

Here is what is seen in the Input Output Reference....

 Construction,
window_const,             !- Name
Usual Glass,              !- Layer 1
AIR 6MM,                  !- Layer 2
TCGlazings,               !- Layer 3
AIR 6MM,                  !- Layer 4
Usual Glass;              !- Layer 5

WindowMaterial:Gas,
AIR 6MM,                 !- Name
Air,                     !- Gas Type
0.0063;                  !- Thickness {m}

WindowMaterial:GlazingGroup:Thermochromic,
TCGlazings,
0 ,  TCGlazing0,
20,  TCGlazing20,
25,  TCGlazing25,
30,  TCGlazing30,
35,  TCGlazing35,
40,  TCGlazing40,
45,  TCGlazing45,
50,  TCGlazing50,
55,  TCGlazing55,
60,  TCGlazing60,
65,  TCGlazing65,
75,  TCGlazing75,
85,  TCGlazing85;

WindowMaterial:Glazing,
TCGlazing0,  !- Name
SpectralAverage,  !- Optical Data Type
,        !- Window Glass Spectral Data Set Name
0.0030,  !- Thickness
0.2442,  !- Solar Transmittance at Normal Incidence
0.7058,  !- Front Side Solar Reflectance at Normal Incidence
0.7058,  !- Back Side Solar Reflectance at Normal Incidence
0.3192,  !- Visible Transmittance at Normal Incidence
0.6308,  !- Front Side Visible Reflectance at Normal Incidence
0.6308,  !- Back Side Visible Reflectance at Normal Incidence
0.0000,  !- Infrared Transmittance at Normal Incidence
0.9000,  !- Front Side Infrared Hemispherical Emissivity
0.9000,  !- Back Side Infrared Hemispherical Emissivity
0.0199,  !- Conductivity
1.0000,  !- Dirt Correction Factor for Solar and Visible Transmittance
No;      !- Solar Diffusing

WindowMaterial:Glazing,
TCGlazing20,  !- Name
SpectralAverage,  !- Optical Data Type
,        !- Window Glass Spectral Data Set Name
0.0030,  !- Thickness
0.2442,  !- Solar Transmittance at Normal Incidence
0.7058,  !- Front Side Solar Reflectance at Normal Incidence
0.7058,  !- Back Side Solar Reflectance at Normal Incidence
0.3192,  !- Visible Transmittance at Normal Incidence
0.6308,  !- Front Side Visible Reflectance at Normal Incidence
0.6308,  !- Back Side Visible Reflectance at Normal Incidence
0.0000,  !- Infrared Transmittance at Normal Incidence
0.9000,  !- Front Side Infrared Hemispherical Emissivity
0.9000,  !- Back Side Infrared Hemispherical Emissivity
0.0199,  !- Conductivity
1.0000,  !- Dirt Correction Factor for Solar and Visible Transmittance
No;      !- Solar Diffusing


EDIT: Here is what is seen in ThermochromicWindow.idf(This time just including the construction for the coldest (25°C) and warmest (85°C) temperatures) In this case the spectral data is slightly different for each window. Is that the correct way to handle the differences?

 Construction,
TCwindow,                !- Name
Clear3PPG,               !- Outside Layer
AIR 3MM,                 !- Layer 2
TCGlazings,              !- Layer 3
AIR 8MM,                 !- Layer 4
SB60Clear3PPG;           !- Layer 5

WindowMaterial:GlazingGroup:Thermochromic,
TCGlazings,              !- Name
25,                      !- Optical Data Temperature 1 {C}
WO18RT25,                !- Window Material Glazing Name 1
27,                      !- Optical Data Temperature 2 {C}
WO18RT27,                !- Window Material Glazing Name 2
29,                      !- Optical Data Temperature 3 {C}
WO18RT29,                !- Window Material Glazing Name 3
31,                      !- Optical Data Temperature 4 {C}
WO18RT31,                !- Window Material Glazing Name 4
33,                      !- Optical Data Temperature 5 {C}
WO18RT33,                !- Window Material Glazing Name 5
35,                      !- Optical Data Temperature 6 {C}
WO18RT35,                !- Window Material Glazing Name 6
37,                      !- Optical Data Temperature 7 {C}
WO18RT37,                !- Window Material Glazing Name 7
39,                      !- Optical Data Temperature 8 {C}
WO18RT39,                !- Window Material Glazing Name 8
41,                      !- Optical Data Temperature 9 {C}
WO18RT41,                !- Window Material Glazing Name 9
43,                      !- Optical Data Temperature 10 {C}
WO18RT43,                !- Window Material Glazing Name 10
45,                      !- Optical Data Temperature 11 {C}
WO18RT45,                !- Window Material Glazing Name 11
50,                      !- Optical Data Temperature 12 {C}
WO18RT50,                !- Window Material Glazing Name 12
55,                      !- Optical Data Temperature 13 {C}
WO18RT55,                !- Window Material Glazing Name 13
60,                      !- Optical Data Temperature 14 {C}
WO18RT60,                !- Window Material Glazing Name 14
65,                      !- Optical Data Temperature 15 {C}
WO18RT65,                !- Window Material Glazing Name 15
70,                      !- Optical Data Temperature 16 {C}
WO18RT70,                !- Window Material Glazing Name 16
75,                      !- Optical Data Temperature 17 {C}
WO18RT75,                !- Window Material Glazing Name 17
80,                      !- Optical Data Temperature 18 {C}
WO18RT80,                !- Window Material Glazing Name 18
85,                      !- Optical Data Temperature 19 {C}
WO18RT85;                !- Window Material Glazing Name 19

WindowMaterial:Glazing,
WO18RT25,                !- Name
Spectral,                !- Optical Data Type
WO18RT25SP,              !- Window Glass Spectral Data Set Name
0.0075,                  !- Thickness {m}
,                        !- Solar Transmittance at Normal Incidence
,                        !- Front Side Solar Reflectance at Normal Incidence
,                        !- Back Side Solar Reflectance at Normal Incidence
,                        !- Visible Transmittance at Normal Incidence
,                        !- Front Side Visible Reflectance at Normal Incidence
,                        !- Back Side Visible Reflectance at Normal Incidence
0,                       !- Infrared Transmittance at Normal Incidence
0.84,                    !- Front Side Infrared Hemispherical Emissivity
0.84,                    !- Back Side Infrared Hemispherical Emissivity
0.6,                     !- Conductivity {W/m-K}
1.0,                     !- Dirt Correction Factor for Solar and Visible Transmittance
No;                      !- Solar Diffusing

WindowMaterial:Glazing,
WO18RT85,                !- Name
Spectral,                !- Optical Data Type
WO18RT85SP,              !- Window Glass Spectral Data Set Name
0.0075,                  !- Thickness {m}
,                        !- Solar Transmittance at Normal Incidence
,                        !- Front Side Solar Reflectance at Normal Incidence
,                        !- Back Side Solar Reflectance at Normal Incidence
,                        !- Visible Transmittance at Normal Incidence
,                        !- Front Side Visible Reflectance at Normal Incidence
,                        !- Back Side Visible Reflectance at Normal Incidence
0,                       !- Infrared Transmittance at Normal Incidence
0.84,                    !- Front Side Infrared Hemispherical Emissivity
0.84,                    !- Back Side Infrared Hemispherical Emissivity
0.6,                     !- Conductivity {W/m-K}
1.0,                     !- Dirt Correction Factor for Solar and Visible Transmittance
No;                      !- Solar Diffusing

 3 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### Thermochromic IDF Example Explanation

Does anyone know why the idf example both in the Input Output Reference and the idf example file use different glazing materials all with the exact same properties for WindowMaterial:GlazingGroup:Thermochromic? I believe the solar transmittance should be decreasing for higher temperatures. I have provided two of the materials for here for quick comparison, all twelve look the same to me though.

Here is what is seen in the Input Output Reference....

 Construction,
window_const,             !- Name
Usual Glass,              !- Layer 1
AIR 6MM,                  !- Layer 2
TCGlazings,               !- Layer 3
AIR 6MM,                  !- Layer 4
Usual Glass;              !- Layer 5

WindowMaterial:Gas,
AIR 6MM,                 !- Name
Air,                     !- Gas Type
0.0063;                  !- Thickness {m}

WindowMaterial:GlazingGroup:Thermochromic,
TCGlazings,
0 ,  TCGlazing0,
20,  TCGlazing20,
25,  TCGlazing25,
30,  TCGlazing30,
35,  TCGlazing35,
40,  TCGlazing40,
45,  TCGlazing45,
50,  TCGlazing50,
55,  TCGlazing55,
60,  TCGlazing60,
65,  TCGlazing65,
75,  TCGlazing75,
85,  TCGlazing85;

WindowMaterial:Glazing,
TCGlazing0,  !- Name
SpectralAverage,  !- Optical Data Type
,        !- Window Glass Spectral Data Set Name
0.0030,  !- Thickness
0.2442,  !- Solar Transmittance at Normal Incidence
0.7058,  !- Front Side Solar Reflectance at Normal Incidence
0.7058,  !- Back Side Solar Reflectance at Normal Incidence
0.3192,  !- Visible Transmittance at Normal Incidence
0.6308,  !- Front Side Visible Reflectance at Normal Incidence
0.6308,  !- Back Side Visible Reflectance at Normal Incidence
0.0000,  !- Infrared Transmittance at Normal Incidence
0.9000,  !- Front Side Infrared Hemispherical Emissivity
0.9000,  !- Back Side Infrared Hemispherical Emissivity
0.0199,  !- Conductivity
1.0000,  !- Dirt Correction Factor for Solar and Visible Transmittance
No;      !- Solar Diffusing

WindowMaterial:Glazing,
TCGlazing20,  !- Name
SpectralAverage,  !- Optical Data Type
,        !- Window Glass Spectral Data Set Name
0.0030,  !- Thickness
0.2442,  !- Solar Transmittance at Normal Incidence
0.7058,  !- Front Side Solar Reflectance at Normal Incidence
0.7058,  !- Back Side Solar Reflectance at Normal Incidence
0.3192,  !- Visible Transmittance at Normal Incidence
0.6308,  !- Front Side Visible Reflectance at Normal Incidence
0.6308,  !- Back Side Visible Reflectance at Normal Incidence
0.0000,  !- Infrared Transmittance at Normal Incidence
0.9000,  !- Front Side Infrared Hemispherical Emissivity
0.9000,  !- Back Side Infrared Hemispherical Emissivity
0.0199,  !- Conductivity
1.0000,  !- Dirt Correction Factor for Solar and Visible Transmittance
No;      !- Solar Diffusing


EDIT: Here is what is seen in ThermochromicWindow.idf(This time just including the construction for the coldest (25°C) and warmest (85°C) temperatures) In this case the spectral data is slightly different for each window. Is that the correct way to handle the differences?

 Construction,
TCwindow,                !- Name
Clear3PPG,               !- Outside Layer
AIR 3MM,                 !- Layer 2
TCGlazings,              !- Layer 3
AIR 8MM,                 !- Layer 4
SB60Clear3PPG;           !- Layer 5

WindowMaterial:GlazingGroup:Thermochromic,
TCGlazings,              !- Name
25,                      !- Optical Data Temperature 1 {C}
WO18RT25,                !- Window Material Glazing Name 1
27,                      !- Optical Data Temperature 2 {C}
WO18RT27,                !- Window Material Glazing Name 2
29,                      !- Optical Data Temperature 3 {C}
WO18RT29,                !- Window Material Glazing Name 3
31,                      !- Optical Data Temperature 4 {C}
WO18RT31,                !- Window Material Glazing Name 4
33,                      !- Optical Data Temperature 5 {C}
WO18RT33,                !- Window Material Glazing Name 5
35,                      !- Optical Data Temperature 6 {C}
WO18RT35,                !- Window Material Glazing Name 6
37,                      !- Optical Data Temperature 7 {C}
WO18RT37,                !- Window Material Glazing Name 7
39,                      !- Optical Data Temperature 8 {C}
WO18RT39,                !- Window Material Glazing Name 8
41,                      !- Optical Data Temperature 9 {C}
WO18RT41,                !- Window Material Glazing Name 9
43,                      !- Optical Data Temperature 10 {C}
WO18RT43,                !- Window Material Glazing Name 10
45,                      !- Optical Data Temperature 11 {C}
WO18RT45,                !- Window Material Glazing Name 11
50,                      !- Optical Data Temperature 12 {C}
WO18RT50,                !- Window Material Glazing Name 12
55,                      !- Optical Data Temperature 13 {C}
WO18RT55,                !- Window Material Glazing Name 13
60,                      !- Optical Data Temperature 14 {C}
WO18RT60,                !- Window Material Glazing Name 14
65,                      !- Optical Data Temperature 15 {C}
WO18RT65,                !- Window Material Glazing Name 15
70,                      !- Optical Data Temperature 16 {C}
WO18RT70,                !- Window Material Glazing Name 16
75,                      !- Optical Data Temperature 17 {C}
WO18RT75,                !- Window Material Glazing Name 17
80,                      !- Optical Data Temperature 18 {C}
WO18RT80,                !- Window Material Glazing Name 18
85,                      !- Optical Data Temperature 19 {C}
WO18RT85;                !- Window Material Glazing Name 19

WindowMaterial:Glazing,
WO18RT25,                !- Name
Spectral,                !- Optical Data Type
WO18RT25SP,              !- Window Glass Spectral Data Set Name
0.0075,                  !- Thickness {m}
,                        !- Solar Transmittance at Normal Incidence
,                        !- Front Side Solar Reflectance at Normal Incidence
,                        !- Back Side Solar Reflectance at Normal Incidence
,                        !- Visible Transmittance at Normal Incidence
,                        !- Front Side Visible Reflectance at Normal Incidence
,                        !- Back Side Visible Reflectance at Normal Incidence
0,                       !- Infrared Transmittance at Normal Incidence
0.84,                    !- Front Side Infrared Hemispherical Emissivity
0.84,                    !- Back Side Infrared Hemispherical Emissivity
0.6,                     !- Conductivity {W/m-K}
1.0,                     !- Dirt Correction Factor for Solar and Visible Transmittance
No;                      !- Solar Diffusing

WindowMaterial:Glazing,
WO18RT85,                !- Name
Spectral,                !- Optical Data Type
WO18RT85SP,              !- Window Glass Spectral Data Set Name
0.0075,                  !- Thickness {m}
,                        !- Solar Transmittance at Normal Incidence
,                        !- Front Side Solar Reflectance at Normal Incidence
,                        !- Back Side Solar Reflectance at Normal Incidence
,                        !- Visible Transmittance at Normal Incidence
,                        !- Front Side Visible Reflectance at Normal Incidence
,                        !- Back Side Visible Reflectance at Normal Incidence
0,                       !- Infrared Transmittance at Normal Incidence
0.84,                    !- Front Side Infrared Hemispherical Emissivity
0.84,                    !- Back Side Infrared Hemispherical Emissivity
0.6,                     !- Conductivity {W/m-K}
1.0,                     !- Dirt Correction Factor for Solar and Visible Transmittance
No;                      !- Solar Diffusing