// Numbas version: exam_results_page_options
{"name": "Fault Analysis 4 Bus", "extensions": [], "custom_part_types": [], "resources": [["question-resources/FA4Bus.png", "/srv/numbas/media/question-resources/FA4Bus.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "Fault Analysis 4 Bus", "tags": [], "metadata": {"description": "", "licence": "None specified"}, "statement": "<p style=\"text-align: center;\">In the system shown in <strong>Figure 1</strong>, the transformers&nbsp;are connected star-star with both star points grounded and the generators&nbsp;are connected in star with thier star points grounded. The per unit sequence reactances of each element on a {SBASE} MVA base are given in <strong>Table 1</strong>.</p>\n<p style=\"text-align: center;\">{image('resources/question-resources/FA4Bus.png')}</p>\n<p style=\"text-align: center;\"><strong><em>Figure 1: A section of the distribution system</em></strong></p>\n<table border=\"1\" cellpadding=\"1\" style=\"margin-left: auto; margin-right: auto;\">\n<tbody>\n<tr>\n<td width=\"74\" style=\"text-align: center;\">\n<p>&nbsp;</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p><strong>G1</strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p><strong>T1</strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p style=\"text-align: center;\"><strong>L</strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p style=\"text-align: center;\"><strong>T2</strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p style=\"text-align: center;\"><strong>G2</strong></p>\n</td>\n</tr>\n<tr>\n<td width=\"74\" style=\"text-align: center;\">\n<p><strong>X<sub>1</sub></strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{G112}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{T1}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{L12}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{T2}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{G212}</p>\n</td>\n</tr>\n<tr>\n<td width=\"74\" style=\"text-align: center;\">\n<p><strong>X<sub>2</sub></strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{G112}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{T1}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{L12}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{T2}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{G212}</p>\n</td>\n</tr>\n<tr>\n<td width=\"74\" style=\"text-align: center;\">\n<p><strong>X<sub>0</sub></strong></p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{G10}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{T1}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{L0}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{T2}</p>\n</td>\n<td width=\"74\" style=\"text-align: center;\">\n<p>{G20}</p>\n</td>\n</tr>\n</tbody>\n</table>\n<p style=\"text-align: center;\"><em><strong></strong></em><em><strong>&nbsp;Table 1: Sequence reactances (p.u. on {SBASE} MVA base)</strong></em></p>", "advice": "", "rulesets": {}, "extensions": [], "variables": {"G112": {"name": "G112", "group": "Ungrouped variables", "definition": "random(0.05 .. 0.2#0.01)", "description": "", "templateType": "randrange"}, "G10": {"name": "G10", "group": "Ungrouped variables", "definition": "precround(ratio*G112,2)", "description": "", "templateType": "anything"}, "L0": {"name": "L0", "group": "Ungrouped 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