function descargar_balanseo(){
	document.getElementById('boton_descarga').style.visibility='hidden';
	var capa = document.getElementById('capa_balanseo');
	iframe = document.createElement('iframe');
    iframe.setAttribute('src','descargar_balanseo.html');  		    	
    iframe.setAttribute('frameBorder','0');  		    	
    iframe.setAttribute('width','400');  		    		
    iframe.setAttribute('height','40');  
    iframe.setAttribute('scrolling','No');  
    iframe.setAttribute('allowTransparency','true');  
    capa.appendChild(iframe);
	return;
}