diff --git a/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php b/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
index abebe8b..5bcf9cb 100644
--- a/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
+++ b/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
@@ -779,7 +779,7 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 		}
 		else
 		{
-			$orbitSerie = $paramNode->addOrbitSerie($paramData->{'param-drawing-object'}->{'serie-yaxis'}, $xAxis, $colorSerieId);
+			$orbitSerie = $paramNode->addOrbitSerie($paramData->{'param-drawing-object'}->{'serie-yaxis'}, $colorSerieId);
 			$orbitSerie->setId($paramData->{'id'});
 			$serieNodes[] = $orbitSerie;
 		}
@@ -968,7 +968,7 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 	
 	protected function unmarshallInstantSerie($paramDrawingData, $plotNode, $paramNode)
 	{
-		$iserieNode = $paramNode->addInstantSerie(REQUESTOUTPUTPLOTELEMENTXY_XAXISID, 'y-left');
+		$iserieNode = $paramNode->addInstantSerie('y-left');
 		
 		//Table on X Axis
 		$iserieNode->setTableOnXAxis($paramDrawingData->{'iserie-tableonx'} ? "true" : "false");
@@ -991,7 +991,7 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 	protected function unmarshallInstantSpectro($paramDrawingData, $plotNode, $paramNode, $indexes)
 	{
 	//TBD how to process inexes if they are defined ? 
-		$spectroNode = $paramNode->addInstantSpectro(REQUESTOUTPUTPLOTELEMENTXY_XAXISID, 'y-left', $paramDrawingData->{'ispectro-dimonxaxis'});
+		$spectroNode = $paramNode->addInstantSpectro('y-left', $paramDrawingData->{'ispectro-dimonxaxis'});
 	}
 	
 	protected function unmarshallStatusBar($paramDrawingData, $paramNode, $indexes)
diff --git a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotBaseSerieNodeClass.php b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotBaseSerieNodeClass.php
index 42ed418..acd4c4e 100644
--- a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotBaseSerieNodeClass.php
+++ b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotBaseSerieNodeClass.php
@@ -7,7 +7,6 @@ require_once "RequestOutputPlotSerieIntervalTicksNodeClass.php";
 
 define ("REQUESTOUTPUTPLOTBASESERIE_XAXIS", "xAxis");
 define ("REQUESTOUTPUTPLOTBASESERIE_YAXIS", "yAxis");
-define ("REQUESTOUTPUTPLOTBASESERIE_XID", "xId");
 define ("REQUESTOUTPUTPLOTBASESERIE_COLORSERIEID", "colorSerieId");
 define ("REQUESTOUTPUTPLOTBASESERIE_MIN", "min");
 define ("REQUESTOUTPUTPLOTBASESERIE_MAX", "max");
@@ -29,24 +28,24 @@ class RequestOutputPlotBaseSerieNodeClass extends NodeClass
 		parent::__construct($name);
 	}
 
-	public function setYAxisId($axisId)
+	public function setXAxisId($axisId)
 	{
-		$this->setAttribute(REQUESTOUTPUTPLOTBASESERIE_YAXIS, $axisId);
+		$this->setAttribute(REQUESTOUTPUTPLOTBASESERIE_XAXIS, $axisId);
 	}
 
-	public function getYAxisId()
+	public function getXAxisId()
 	{
-		return $this->getAttribute(REQUESTOUTPUTPLOTBASESERIE_YAXIS);
+		return $this->getAttribute(REQUESTOUTPUTPLOTBASESERIE_XAXIS);
 	}
-	
-	public function setXId($xId)
+
+	public function setYAxisId($axisId)
 	{
-		$this->setAttribute(REQUESTOUTPUTPLOTBASESERIE_XID, $xId);
+		$this->setAttribute(REQUESTOUTPUTPLOTBASESERIE_YAXIS, $axisId);
 	}
-	
-	public function getXId()
+
+	public function getYAxisId()
 	{
-		return $this->getAttribute(REQUESTOUTPUTPLOTBASESERIE_XID);
+		return $this->getAttribute(REQUESTOUTPUTPLOTBASESERIE_YAXIS);
 	}
 	
 	public function setColorSerieId($colorSerieId)
diff --git a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php
index 3d1324c..ee24e61 100644
--- a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php
+++ b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php
@@ -83,21 +83,21 @@ class RequestOutputPlotParamNodeClass extends NodeClass
 		return $ySerieNode;
 	}
 	
-	public function addOrbitSerie($yAxis, $xId, $colorSerieId = -1)
+	public function addOrbitSerie($yAxis, $colorSerieId = -1)
 	{
 		$orbitSerieNode = new RequestOutputPlotOrbitSerieNodeClass();
+		$orbitSerieNode->setXAxisId(REQUESTOUTPUTPLOTELEMENTXY_XAXISID);
 		$orbitSerieNode->setYAxisId($yAxis);
-		$orbitSerieNode->setXId($xId);
 		if ($colorSerieId >= 0)
 			$orbitSerieNode->setColorSerieId($colorSerieId);
 		$this->addChild($orbitSerieNode);
 		return $orbitSerieNode;
 	}
 	
-	public function addInstantSerie($xId, $yAxis)
+	public function addInstantSerie($yAxis)
 	{
 		$iserieNode = new RequestOutputPlotInstantSerieNodeClass();
-		$iserieNode->setXId($xId);
+		$iserieNode->setXAxisId(REQUESTOUTPUTPLOTELEMENTXY_XAXISID);
 		$iserieNode->setYAxisId($yAxis);
 		$this->addChild($iserieNode);
 		return $iserieNode;
@@ -118,10 +118,10 @@ class RequestOutputPlotParamNodeClass extends NodeClass
 		return $spectroNode;
 	}
 	
-	public function addInstantSpectro($xId, $yAxis, $dimOnXAxis, $index = NULL, $min = NULL, $max = NULL)
+	public function addInstantSpectro($yAxis, $dimOnXAxis, $index = NULL, $min = NULL, $max = NULL)
 	{
 		$ispectroNode = new NodeClass(REQUESTOUTPUTPLOTINSTANTSPECTRO_NAME);
-		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTINSTANTSPECTRO_ID, $xId);
+		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTINSTANTSPECTRO_XAXIS, REQUESTOUTPUTPLOTELEMENTXY_XAXISID);
 		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTSPECTRO_YAXIS, $yAxis);
 		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTINSTANTSPECTRO_DIMONXAXIS, $dimOnXAxis);
 		
diff --git a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotYSerieNodeClass.php b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotYSerieNodeClass.php
index c509631..e0da856 100644
--- a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotYSerieNodeClass.php
+++ b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotYSerieNodeClass.php
@@ -6,6 +6,7 @@ require_once "RequestOutputPlotYSerieErrorBarNodeClass.php";
 define ("REQUESTOUTPUTPLOTYSERIE_XYPLOT_NAME", "yserie");
 define ("REQUESTOUTPUTPLOTYSERIE_TIMEPLOT_NAME", "serie");
 
+define ("REQUESTOUTPUTPLOTYSERIE_XID", "xId");
 define ("REQUESTOUTPUTPLOTYSERIE_INDEX", "index");
 define ("REQUESTOUTPUTPLOTYSERIE_RESAMPLING", "resampling");
 define ("REQUESTOUTPUTPLOTYSERIE_ERRORBAR", "errorBar");
@@ -22,16 +23,6 @@ class RequestOutputPlotYSerieNodeClass extends RequestOutputPlotBaseSerieNodeCla
 		parent::__construct($name);
 	}
 
-	public function setXAxisId($axisId)
-	{
-		$this->setAttribute(REQUESTOUTPUTPLOTBASESERIE_XAXIS, $axisId);
-	}
-
-	public function getXAxisId()
-	{
-		return $this->getAttribute(REQUESTOUTPUTPLOTBASESERIE_XAXIS);
-	}
-
 	public function setIndex($index)
 	{
 		$this->setAttribute(REQUESTOUTPUTPLOTYSERIE_INDEX, $index);
@@ -41,6 +32,16 @@ class RequestOutputPlotYSerieNodeClass extends RequestOutputPlotBaseSerieNodeCla
 	{
 		return $this->getAttribute(REQUESTOUTPUTPLOTYSERIE_INDEX);
 	}
+
+	public function setXId($xId)
+	{
+		$this->setAttribute(REQUESTOUTPUTPLOTYSERIE_XID, $xId);
+	}
+
+	public function getXId()
+	{
+		return $this->getAttribute(REQUESTOUTPUTPLOTYSERIE_XID);
+	}
 	
 	public function getResampling()
 	{
@@ -71,6 +72,10 @@ class RequestOutputPlotYSerieNodeClass extends RequestOutputPlotBaseSerieNodeCla
 	public function loadFromNode($xmlNode)
 	{
 		$this->setIndex($this->getXmlNodeAttribute($xmlNode, REQUESTOUTPUTPLOTYSERIE_INDEX));
+
+		$xId = $this->getXmlNodeAttribute($xmlNode, REQUESTOUTPUTPLOTYSERIE_XID);
+		if (!empty($xId))
+			$this->setXId($this->getXmlNodeAttribute($xmlNode, REQUESTOUTPUTPLOTYSERIE_XID));
 		
 		$resamplingXmlNode = $this->getXmlNodeChildByTagName($xmlNode, REQUESTOUTPUTPLOTYSERIE_RESAMPLING);
 		if (isset($resamplingXmlNode))
--
libgit2 0.21.2