text: 
      google.charts.load('current', {'packages':['corechart']});
        
      // Set a callback to run when the Google Visualization API is loaded.
      google.charts.setOnLoadCallback(drawChart1);
  	 var dataTable1,dataTable2,dataTable3,dataTable4=null;
  	 var chart1,chart2,chart3,chart4=null;
  	 var options1,options2,options3,options4;
        
     function drawChart1() {
  	  
  	  $.getJSON('action_graph_week.php/?c=0', function(json) {
  	 // alert(JSON.stringify(json));
  	  dataTable1 = new google.visualization.DataTable()		
  			
  			dataTable1.addColumn('datetime',   'Time');
  			 dataTable1.addColumn('number', 'Current');
  			 for(i=0;i <json.length; i++)
  			 { 
  			  console.log(json[i].Time);
  			  
  			  dataTable1.addRow([new Date(json[i].Time), parseInt(json[i].Current)]);
  			 }
  			 
  		options1 = {
  		chartArea: {width: '85%' , height: '80%'},
            title: 'Sensor',
            curveType: 'function',
  		  pointSize: 1,
  		   vAxis: { viewWindow:{min:0}, minValue:0, maxValue:10},
  		  pointShape: 'circle',	
            legend: { position: 'top' }
          };
          chart1 = new google.visualization.LineChart(document.getElementById('line_chart1'));
  
          chart1.draw(dataTable1, options1);
  		
  		//-----------------------------------------------------
  		dataTable2 = new google.visualization.DataTable()		
  			
  			dataTable2.addColumn('datetime',   'Time');
  			 dataTable2.addColumn('number', 'Voltage');
  			 for(i=0;i <json.length; i++)
  			 { 
  			  
  			  dataTable2.addRow([new Date(json[i].Time), parseInt(json[i].Voltage)]);
  			 }
  			 
  		options2 = {
  		chartArea: {width: '85%' , height: '80%'},
            title: 'Sensor',
            curveType: 'function',
  		  pointSize: 1,
  		   vAxis: {viewWindow:{min:0},minValue:0, maxValue:10},
  		  pointShape: 'circle',	
            legend: { position: 'top' }
          };
          chart2= new google.visualization.LineChart(document.getElementById('line_chart2'));
  
          chart2.draw(dataTable2, options2);
  		//---------------------------------------------------------
  		dataTable3 = new google.visualization.DataTable()		
  			
  			dataTable3.addColumn('datetime',   'Time');
  			 dataTable3.addColumn('number', 'Frequency');
  			 for(i=0;i <json.length; i++)
  			 { 
  			 
  			  dataTable3.addRow([new Date(json[i].Time), parseInt(json[i].Frequency	)]);
  			 }
  			 
  		options3 = {
  		chartArea: {width: '85%' , height: '80%'},
            title: 'Sensor',
            curveType: 'function',
  		  pointSize: 1,
  		   vAxis: {viewWindow:{min:0},minValue:0, maxValue:10},
  		  pointShape: 'circle',	
            legend: { position: 'top' }
          };
          chart3 = new google.visualization.LineChart(document.getElementById('line_chart3'));
  
          chart3.draw(dataTable3, options3);
  		//------------------------------------------------------
  		dataTable4 = new google.visualization.DataTable()		
  			
  			dataTable4.addColumn('datetime',   'Time');
  			 dataTable4.addColumn('number', 'Phase');
  			 for(i=0;i <json.length; i++)
  			 { 
  			 
  			  dataTable4.addRow([new Date(json[i].Time), parseInt(json[i].Phase)]);
  			 }
  			 
  		options4 = {
  		chartArea: {width: '85%' , height: '80%'},
            title: 'Sensor',
            curveType: 'function',
  		  pointSize: 1,
  		   vAxis: {viewWindow:{min:0},minValue:0, maxValue:10},
  		  pointShape: 'circle',	
            legend: { position: 'top' }
          };
          chart4= new google.visualization.LineChart(document.getElementById('line_chart4'));
  
          chart4.draw(dataTable4, options4);
  		
  		});
  		}
  