bug：在同一页面绘制两个完全相同的AmCharts折线图，只有一个正常

学做AmCharts最简单的折线图时，在同一个页面放了两个一样的折线图，结果只有后面一个显示正常。

var chartData =
        [{
            "org_name": "USA",
            "org_tel": 3025,
            "color": "#FF0F00"
        }, {
            "org_name": "China",
            "org_tel": 1882,
            "color": "#FF6600"
        }, {
            "org_name": "Japan",
            "org_tel": 1809,
            "color": "#FF9E01"
        }, {
            "org_name": "Germany",
            "org_tel": 1322,
            "color": "#FCD202"
        }, {
            "org_name": "UK",
            "org_tel": 1122,
            "color": "#F8FF01"
        }, {
            "org_name": "France",
            "org_tel": 1114,
            "color": "#B0DE09"
        }, {
            "org_name": "India",
            "org_tel": 984,
            "color": "#04D215"
        }, {
            "org_name": "Spain",
            "org_tel": 711,
            "color": "#0D8ECF"
        }];
var options = {
    type: "serial",
    dataProvider: chartData,
    categoryField: "org_name",
    categoryAxis: {
        gridPosition: "start"
    },
    valueAxes: [{
        title: "Million USD"
    }],
    graphs: [{
        type: "line",
        title: "title",
        valueField: "org_tel",
        lineAlpha: 0,
        fillAlphas: 0.8,
        balloonText: "[[category]]: <b>[[value]]</b>",
    }]
};

var chartData2 = chartData;
var options_2 = options;
setTimeout(function() {
    console.log("ready for chart3");
    var testSerialChart = AmCharts.makeChart("health", options);// health 是div的id，下面的“online”一样
    var testSerialChart2 = AmCharts.makeChart("online", options_2);
}, 200);