Why is tension in cable not activating?

Ok i tried it with perform cable analysis, even though the deflection have reduced but still it looks unrealistic

STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 05-Sep-19
END JOB INFORMATION
INPUT WIDTH 79
UNIT METER KN
JOINT COORDINATES
1 0 0 0; 2 0 3 0; 3 0 5.4 0; 4 0 7.8 0; 5 0 10.2 0; 6 0 12.6 0; 7 0 14.7 0;
8 0 15 0; 9 0.5 0 0; 10 0.5 3 0; 11 0.5 5.4 0; 12 0.5 7.8 0; 13 0.5 10.2 0;
14 0.5 12.6 0; 15 0.5 14.7 0; 16 0.5 15 0; 17 2 0 0; 18 2 3 0; 19 2 5.4 0;
20 2 7.8 0; 21 2 10.2 0; 22 2 12.6 0; 23 2 14.7 0; 24 2 15 0; 25 3.5 0 0;
26 3.5 3 0; 27 3.5 5.4 0; 28 3.5 7.8 0; 29 3.5 10.2 0; 30 3.5 12.6 0;
31 3.5 14.7 0; 32 3.5 15 0; 33 5 0 0; 34 5 3 0; 35 5 5.4 0; 36 5 7.8 0;
37 5 10.2 0; 38 5 12.6 0; 39 5 14.7 0; 40 5 15 0; 41 6.5 0 0; 42 6.5 3 0;
43 6.5 5.4 0; 44 6.5 7.8 0; 45 6.5 10.2 0; 46 6.5 12.6 0; 47 6.5 14.7 0;
48 6.5 15 0; 50 8 3 0; 51 8 5.4 0; 52 8 7.8 0; 53 8 10.2 0; 54 8 12.6 0;
55 8 14.7 0; 56 8 15 0; 58 9.5 3 0; 59 9.5 5.4 0; 60 9.5 7.8 0; 61 9.5 10.2 0;
62 9.5 12.6 0; 63 9.5 14.7 0; 64 9.5 15 0; 66 11 3 0; 67 11 5.4 0; 68 11 7.8 0;
69 11 10.2 0; 70 11 12.6 0; 71 11 14.7 0; 72 11 15 0; 74 12.5 3 0;
75 12.5 5.4 0; 76 12.5 7.8 0; 77 12.5 10.2 0; 78 12.5 12.6 0; 79 12.5 14.7 0;
80 12.5 15 0; 82 14 3 0; 83 14 5.4 0; 84 14 7.8 0; 85 14 10.2 0; 86 14 12.6 0;
87 14 14.7 0; 88 14 15 0; 90 15.5 3 0; 91 15.5 5.4 0; 92 15.5 7.8 0;
93 15.5 10.2 0; 94 15.5 12.6 0; 95 15.5 14.7 0; 96 15.5 15 0; 98 17 3 0;
99 17 5.4 0; 100 17 7.8 0; 101 17 10.2 0; 102 17 12.6 0; 103 17 14.7 0;
104 17 15 0; 106 18.5 3 0; 107 18.5 5.4 0; 108 18.5 7.8 0; 109 18.5 10.2 0;
110 18.5 12.6 0; 111 18.5 14.7 0; 112 18.5 15 0; 114 20 3 0; 115 20 5.4 0;
116 20 7.8 0; 117 20 10.2 0; 118 20 12.6 0; 119 20 14.7 0; 120 20 15 0;
122 21.5 3 0; 123 21.5 5.4 0; 124 21.5 7.8 0; 125 21.5 10.2 0; 126 21.5 12.6 0;
127 21.5 14.7 0; 128 21.5 15 0; 129 0.5 3 -0.15; 130 0.5 5.4 -0.15;
131 0.5 7.8 -0.15; 132 0.5 10.2 -0.15; 133 0.5 12.6 -0.15; 134 0.5 14.7 -0.15;
135 2 3 -0.15; 136 2 5.4 -0.15; 137 2 7.8 -0.15; 138 2 10.2 -0.15;
139 2 12.6 -0.15; 140 2 14.7 -0.15; 141 3.5 3 -0.15; 142 3.5 5.4 -0.15;
143 3.5 7.8 -0.15; 144 3.5 10.2 -0.15; 145 3.5 12.6 -0.15; 146 3.5 14.7 -0.15;
147 5 3 -0.15; 148 5 5.4 -0.15; 149 5 7.8 -0.15; 150 5 10.2 -0.15;
151 5 12.6 -0.15; 152 5 14.7 -0.15; 153 6.5 3 -0.15; 154 6.5 5.4 -0.15;
155 6.5 7.8 -0.15; 156 6.5 10.2 -0.15; 157 6.5 12.6 -0.15; 158 6.5 14.7 -0.15;
159 8 3 -0.15; 160 8 5.4 -0.15; 161 8 7.8 -0.15; 162 8 10.2 -0.15;
163 8 12.6 -0.15; 164 8 14.7 -0.15; 165 9.5 3 -0.15; 166 9.5 5.4 -0.15;
167 9.5 7.8 -0.15; 168 9.5 10.2 -0.15; 169 9.5 12.6 -0.15; 170 9.5 14.7 -0.15;
171 11 3 -0.15; 172 11 5.4 -0.15; 173 11 7.8 -0.15; 174 11 10.2 -0.15;
175 11 12.6 -0.15; 176 11 14.7 -0.15; 177 12.5 3 -0.15; 178 12.5 5.4 -0.15;
179 12.5 7.8 -0.15; 180 12.5 10.2 -0.15; 181 12.5 12.6 -0.15;
182 12.5 14.7 -0.15; 183 14 3 -0.15; 184 14 5.4 -0.15; 185 14 7.8 -0.15;
186 14 10.2 -0.15; 187 14 12.6 -0.15; 188 14 14.7 -0.15; 189 15.5 3 -0.15;
190 15.5 5.4 -0.15; 191 15.5 7.8 -0.15; 192 15.5 10.2 -0.15;
193 15.5 12.6 -0.15; 194 15.5 14.7 -0.15; 195 17 3 -0.15; 196 17 5.4 -0.15;
197 17 7.8 -0.15; 198 17 10.2 -0.15; 199 17 12.6 -0.15; 200 17 14.7 -0.15;
201 18.5 3 -0.15; 202 18.5 5.4 -0.15; 203 18.5 7.8 -0.15; 204 18.5 10.2 -0.15;
205 18.5 12.6 -0.15; 206 18.5 14.7 -0.15; 207 20 3 -0.15; 208 20 5.4 -0.15;
209 20 7.8 -0.15; 210 20 10.2 -0.15; 211 20 12.6 -0.15; 212 20 14.7 -0.15;
213 0.5 0 -0.15; 214 2 0 -0.15; 215 3.5 0 -0.15; 216 5 0 -0.15;
217 6.5 0 -0.15; 218 21.5 3 -0.15; 219 21.5 0 -0.15; 220 0.5 11.4 -0.15;
221 2 11.4 -0.15; 222 3.5 11.4 -0.15; 223 5 11.4 -0.15; 224 6.5 11.4 -0.15;
225 8 11.4 -0.15; 226 9.5 11.4 -0.15; 227 11 11.4 -0.15; 228 12.5 11.4 -0.15;
229 14 11.4 -0.15; 230 15.5 11.4 -0.15; 231 17 11.4 -0.15; 232 18.5 11.4 -0.15;
233 20 11.4 -0.15; 234 9.5 0 -0.15; 235 18.5 0 -0.15;
MEMBER INCIDENCES
96 10 129; 97 11 130; 98 12 131; 99 13 132; 100 14 133; 101 15 134; 102 18 135;
103 19 136; 104 20 137; 105 21 138; 106 22 139; 107 23 140; 108 26 141;
109 27 142; 110 28 143; 111 29 144; 112 30 145; 113 31 146; 114 34 147;
115 35 148; 116 36 149; 117 37 150; 118 38 151; 119 39 152; 120 42 153;
121 43 154; 122 44 155; 123 45 156; 124 46 157; 125 47 158; 126 50 159;
127 51 160; 128 52 161; 129 53 162; 130 54 163; 131 55 164; 132 58 165;
133 59 166; 134 60 167; 135 61 168; 136 62 169; 137 63 170; 138 66 171;
139 67 172; 140 68 173; 141 69 174; 142 70 175; 143 71 176; 144 74 177;
145 75 178; 146 76 179; 147 77 180; 148 78 181; 149 79 182; 150 82 183;
151 83 184; 152 84 185; 153 85 186; 154 86 187; 155 87 188; 156 90 189;
157 91 190; 158 92 191; 159 93 192; 160 94 193; 161 95 194; 162 98 195;
163 99 196; 164 100 197; 165 101 198; 166 102 199; 167 103 200; 168 106 201;
169 107 202; 170 108 203; 171 109 204; 172 110 205; 173 111 206; 174 114 207;
175 115 208; 176 116 209; 177 117 210; 178 118 211; 179 119 212; 180 217 153;
181 153 159; 182 159 165; 183 165 171; 184 171 177; 185 177 183; 186 183 189;
187 189 195; 188 195 201; 189 201 207; 190 207 218; 191 218 219; 192 220 132;
193 132 131; 194 131 130; 195 130 129; 196 129 213; 197 221 138; 198 138 137;
199 137 136; 200 136 135; 201 135 214; 202 222 144; 203 144 143; 204 143 142;
205 142 141; 206 141 215; 207 223 150; 208 150 149; 209 149 148; 210 148 147;
211 147 216; 212 224 156; 213 156 155; 214 155 154; 215 154 153; 216 225 162;
217 162 161; 218 161 160; 219 160 159; 220 226 168; 221 168 167; 222 167 166;
223 166 165; 224 227 174; 225 174 173; 226 173 172; 227 172 171; 228 228 180;
229 180 179; 230 179 178; 231 178 177; 232 229 186; 233 186 185; 234 185 184;
235 184 183; 236 230 192; 237 192 191; 238 191 190; 239 190 189; 240 231 198;
241 198 197; 242 197 196; 243 196 195; 244 232 204; 245 204 203; 246 203 202;
247 202 201; 248 233 210; 249 210 209; 250 209 208; 251 208 207; 252 165 234;
253 201 235;
ELEMENT INCIDENCES SHELL
1 8 16 15 7; 2 7 15 14 6; 3 6 14 13 5; 4 5 13 12 4; 5 4 12 11 3; 6 3 11 10 2;
7 2 10 9 1; 8 10 18 17 9; 9 11 19 18 10; 10 12 20 19 11; 11 13 21 20 12;
12 14 22 21 13; 13 15 23 22 14; 14 16 24 23 15; 15 18 26 25 17; 16 19 27 26 18;
17 20 28 27 19; 18 21 29 28 20; 19 22 30 29 21; 20 23 31 30 22; 21 24 32 31 23;
22 26 34 33 25; 23 27 35 34 26; 24 28 36 35 27; 25 29 37 36 28; 26 30 38 37 29;
27 31 39 38 30; 28 32 40 39 31; 29 34 42 41 33; 30 35 43 42 34; 31 36 44 43 35;
32 37 45 44 36; 33 38 46 45 37; 34 39 47 46 38; 35 40 48 47 39; 36 43 51 50 42;
37 44 52 51 43; 38 45 53 52 44; 39 46 54 53 45; 40 47 55 54 46; 41 48 56 55 47;
42 51 59 58 50; 43 52 60 59 51; 44 53 61 60 52; 45 54 62 61 53; 46 55 63 62 54;
47 56 64 63 55; 48 59 67 66 58; 49 60 68 67 59; 50 61 69 68 60; 51 62 70 69 61;
52 63 71 70 62; 53 64 72 71 63; 54 67 75 74 66; 55 68 76 75 67; 56 69 77 76 68;
57 70 78 77 69; 58 71 79 78 70; 59 72 80 79 71; 60 75 83 82 74; 61 76 84 83 75;
62 77 85 84 76; 63 78 86 85 77; 64 79 87 86 78; 65 80 88 87 79; 66 83 91 90 82;
67 84 92 91 83; 68 85 93 92 84; 69 86 94 93 85; 70 87 95 94 86; 71 88 96 95 87;
72 91 99 98 90; 73 92 100 99 91; 74 93 101 100 92; 75 94 102 101 93;
76 95 103 102 94; 77 96 104 103 95; 78 99 107 106 98; 79 100 108 107 99;
80 101 109 108 100; 81 102 110 109 101; 82 103 111 110 102; 83 104 112 111 103;
84 107 115 114 106; 85 108 116 115 107; 86 109 117 116 108; 87 110 118 117 109;
88 111 119 118 110; 89 112 120 119 111; 90 115 123 122 114; 91 116 124 123 115;
92 117 125 124 116; 93 118 126 125 117; 94 119 127 126 118; 95 120 128 127 119;
START GROUP DEFINITION
ELEMENT
_GLASS 1 TO 95
MEMBER
_STRUTS 96 TO 179
_PORTAL 180 TO 191
_CABLE 192 TO 251
END GROUP DEFINITION
ELEMENT PROPERTY
1 TO 95 THICKNESS 0.014
DEFINE MATERIAL START
ISOTROPIC STEEL
E 2.05e+008
POISSON 0.3
DENSITY 76.8195
ALPHA 1.2e-005
DAMP 0.03
TYPE STEEL
STRENGTH FY 253200 FU 407800 RY 1.5 RT 1.2
ISOTROPIC GLASS
E 7.2e+007
POISSON 0.22
DENSITY 25
ALPHA 8.1e-006
END DEFINE MATERIAL
MEMBER PROPERTY DUTCH
192 TO 251 TABLE ST RD20
96 TO 179 TABLE ST RD50
MEMBER PROPERTY BRITISH
180 TO 191 252 253 TABLE ST TUB40020016.0
CONSTANTS
MATERIAL STEEL MEMB 96 TO 253
MATERIAL GLASS MEMB 1 TO 95
SUPPORTS
133 134 139 140 145 146 151 152 157 158 163 164 169 170 175 176 181 182 187 -
188 193 194 199 200 205 206 211 212 PINNED
1 TO 9 16 17 24 25 32 33 40 41 48 56 64 72 80 88 96 104 112 120 122 TO 127 -
128 FIXED BUT FX MX MY MZ
217 219 FIXED
213 TO 216 220 TO 235 FIXED
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 1 LOADTYPE Dead  TITLE DL
SELFWEIGHT Y -1 LIST ALL
PERFORM CABLE ANALYSIS BASIC
CHANGE
LOAD 2 LOADTYPE Wind  TITLE WS
ELEMENT LOAD
1 TO 95 PR GZ 2.1
PERFORM CABLE ANALYSIS BASIC
CHANGE
LOAD 3 LOADTYPE Wind  TITLE WP
ELEMENT LOAD
1 TO 95 PR GZ -2.1
PERFORM CABLE ANALYSIS BASIC
CHANGE
LOAD 4 LOADTYPE Temperature  TITLE TL(+)
TEMPERATURE LOAD
180 TO 191 252 253 TEMP 30
PERFORM CABLE ANALYSIS BASIC
CHANGE
LOAD 5 LOADTYPE Temperature  TITLE TL(-)
TEMPERATURE LOAD
180 TO 191 252 253 TEMP -30
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 6 DL+WS
REPEAT LOAD
1 1.0 2 1.0 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 7 DL+WP
REPEAT LOAD
1 1.0 3 1.0 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 8 DL+TL(+)
REPEAT LOAD
1 1.0 4 1.0 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 9 DL+TL(-)
REPEAT LOAD
1 1.0 5 1.0 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 10 1.6DL
REPEAT LOAD
1 1.6 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 11 1.4DL+1.4WS
REPEAT LOAD
1 1.4 2 1.4 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 12 1.4DL+1.4WP
REPEAT LOAD
1 1.4 3 1.4 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 13 1.2DL+1.4TL(+)
REPEAT LOAD
1 1.2 4 1.4 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD 14 1.2DL+1.4TL(-)
REPEAT LOAD
1 1.2 5 1.4 
PERFORM CABLE ANALYSIS BASIC
CHANGE
MEMBER CABLE
192 TO 251 TENSION 50
LOAD LIST 1 6 TO 14
PARAMETER 1
CODE BS5950
PY 355000 MEMB 180 TO 191 252 253
CHECK CODE MEMB 180 TO 191 252 253
FINISH

Couple of observations. You need to use cable analysis and you need to use the STAAD.Pro Advanced License. Also load cases 6 to 9 seem to be the unfactored cases for which you need to check serviceability only. I have attached a modified file with the cable analysis and the max deflection at node 27 comes out to be around 218 mm. When I increased the tension to a higher value, the deflection reduced further. So you may try increasing the pretension if you want to further reduce the deflections.

Structure1_Cable_Analysis.STD

Dear Sye, First of all thank you very much as usual for helping out. Yes if you see my second post I am doing similar and using 4 load cases to check deflection. However, I am still uncertain even after increasing the tension to 300kN, my deflection is going 150mm. I was expecting a huge reduction based on this high load. It will give me trouble with the reactions with factored load cases so I believe i may have to change the cable to fish belly cable truss system. Also can you please explain me why did you remove the code check on the portal frame? is it not possible to check the steel along with cable system or should i make it separate and apply loads from this model? Also can you please explain what do you mean advanced license? will it give me more options? looking forward to your kind reply. And thanks again for you help it really helped me a lot.

I commented out the code check as it was not relevant for the troubleshooting I was doing. Sorry about the confusion. You can perform cable analysis and carry out steel design in the same file. STAAD.Pro Advanced license allows you to carry out an advanced nonlinear cable analysis and you need that if you are going to perform a cable analysis. The following wiki outlines the other advantages in using the STAAD.Pro Advanced license

https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/11117/what-is-staad-advanced-analysis