var fDesc=new Array(); fDesc[0] = "This tool simulates a control loop consisting of a first order process with deadtime and a PID controller.

The process is specified by the process gain, time constant and dead time. The PID controller has 3 parameters: gain, integral and derivative. Key in these values into the appropriate cells. If the integral time is keyed in as 0, the integral term is ignored.

The response to a step change in the set point is displayed in the chart."; function tShowHide(id, show) { var s = document.getElementById("desc"); if ((s.innerHTML.length<=212 || show==1) && show!=2) { s.innerHTML = fDesc[id]; if (document.getElementById('m1')) document.getElementById('m1').style.display='none'; if (document.getElementById('m2')) document.getElementById('m2').style.display='none'; if (document.getElementById('more_txt')) document.getElementById('more_txt').style.display='inline'; } else { s.innerHTML = ''; } }