var %CHART% = AmCharts.makeChart("%CHART%", {
    "theme": "none",
    "type": "gauge",
    "axes": [{
        "axisColor": "#67b7dc",
        "axisThickness": 3,
        "endValue": 240,
        "gridInside": false,
        "inside": false,
        "radius": "100%",
        "tickColor": "#67b7dc"
    }, {
        "axisColor": "#fdd400",
        "axisThickness": 3,
        "endValue": 160,
        "radius": "80%",
        "tickColor": "#fdd400"  
    }],
    "arrows": [{
        "color": "#67b7dc",
        "innerRadius": "20%",
        "nailRadius": 0,
        "radius": "85%"
    }]
});

setInterval(randomValue, 2000);

// set random value
function randomValue() {
    var value = Math.round(Math.random() * 240);
    gaugeChart.arrows[0].setValue(value);
}