diff --git a/TestBenchFramework/BenchControl/Sequences/MainSeq.cs b/TestBenchFramework/BenchControl/Sequences/MainSeq.cs
index d70a2fa28..83f099ba5 100644
--- a/TestBenchFramework/BenchControl/Sequences/MainSeq.cs
+++ b/TestBenchFramework/BenchControl/Sequences/MainSeq.cs
@@ -313,10 +313,21 @@ namespace TBF.BenchControl.Sequences
             StateMachine.ControlBoard.ManualUIAllowed = !StateMachine.Procedure.ManualCtrlDisabled;
 
 			Bridge.Bench2UI(ButtonsEtc.StopBtnEn);	/// Enable STOP button
-            
+
 			int newBatchNr = Program.LocalSettings.BatchNr;
             log.FatalFormat("New measurement session started: batch = {0}, procedure = {1}", newBatchNr, StateMachine.Procedure.Name);
 
+            ///
+            /// Clear iperlhead data (including PCB Number, avoid double use)
+            ///
+            foreach (var cmpnt in StateMachine.Components)
+            {
+                if (cmpnt is TestMethods.iPerlCommunication.iPerlHead.IperlHead)
+                {
+                    (cmpnt as TestMethods.iPerlCommunication.iPerlHead.IperlHead).ClearData();
+                }
+            }
+
 			if (selection == Selection.RestoreBatch)
 			{
                 BatchRslts = CreateNewBatchResults(newBatchNr, StateMachine.Procedure);
diff --git a/TestBenchFramework/BenchControl/TestMethods/FlyingStart/FlyingStartSeq.cs b/TestBenchFramework/BenchControl/TestMethods/FlyingStart/FlyingStartSeq.cs
index c4cc7c791..e01cbab8e 100644
--- a/TestBenchFramework/BenchControl/TestMethods/FlyingStart/FlyingStartSeq.cs
+++ b/TestBenchFramework/BenchControl/TestMethods/FlyingStart/FlyingStartSeq.cs
@@ -680,7 +680,7 @@ namespace TBF.BenchControl.TestMethods.FlyingStart
 
 							meterRslt.Error  = Formulas.ErrorFromVolumes(meterRslt.VolumeMeter, meterRslt.VolumeRef);
 
-#if TURA_IPERL || TURA_SPECIAL
+#if TEST_MODE
                             if (!BatchRslts.IsProduction() &&
                                 ((test.Name.ToLower().Contains("q2") && Math.Abs(meterRslt.Error) > 2.0 && Math.Abs(meterRslt.Error) <= 4.0) ||
                                  (test.Name.ToLower().Contains("q1") && Math.Abs(meterRslt.Error) > 5.0 && Math.Abs(meterRslt.Error) <= 10.0)))
diff --git a/TestBenchFramework/BenchControl/TestMethods/FlyingStartMassCollection/FlyingStartMassCollectionSeq.cs b/TestBenchFramework/BenchControl/TestMethods/FlyingStartMassCollection/FlyingStartMassCollectionSeq.cs
index be8c0fe7e..85556ff2e 100644
--- a/TestBenchFramework/BenchControl/TestMethods/FlyingStartMassCollection/FlyingStartMassCollectionSeq.cs
+++ b/TestBenchFramework/BenchControl/TestMethods/FlyingStartMassCollection/FlyingStartMassCollectionSeq.cs
@@ -1018,7 +1018,7 @@ namespace TBF.BenchControl.TestMethods.FlyingStartMassCollection
 
 							meterRslt.Error = Formulas.ErrorFromVolumes(meterRslt.VolumeMeter, meterRslt.VolumeRef);
 
-#if TURA_IPERL || TURA_SPECIAL
+#if TEST_MODE
                             if (!BatchRslts.IsProduction() &&
                                 ((test.Name.ToLower().Contains("q2") && Math.Abs(meterRslt.Error) > 2.0 && Math.Abs(meterRslt.Error) <= 4.0) ||
                                  (test.Name.ToLower().Contains("q1") && Math.Abs(meterRslt.Error) > 5.0 && Math.Abs(meterRslt.Error) <= 10.0)))
@@ -1043,7 +1043,7 @@ namespace TBF.BenchControl.TestMethods.FlyingStartMassCollection
                             }
 #endif
 
-							meterRslt.Passed = (meterRslt.Error >= test.GetErrLimLo(tstRslt.FlowMean) + test.Uncertainty)
+                            meterRslt.Passed = (meterRslt.Error >= test.GetErrLimLo(tstRslt.FlowMean) + test.Uncertainty)
 											&& (meterRslt.Error <= test.GetErrLimHi(tstRslt.FlowMean) - test.Uncertainty)
 											&& (tstRslt.ErrorFlags == 0 || tstRslt.ErrorFlagsMode() != Config.Entities.ErrorFlagsMode.On);
 							meterRslt.TestDone = true;
diff --git a/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs b/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs
index 486bcf481..3b91d0b6e 100644
--- a/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs
+++ b/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs
@@ -802,7 +802,7 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication
         {
             ///
             /// The activity is "Read configuration" (this enables the watermeter, resets error flag)
-            /// or "Read configuration if enabled" (this keeps th error flag).
+            /// or "Read configuration if enabled" (this keeps the error flag).
             /// 
 			if (!multiTestParams[currentActivityStep].Activity.ToLower().Contains(" if enabled"))
 			{
@@ -811,6 +811,8 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication
 
             if (ihead.CommFailed) return CommErr.CommFailed;
 
+            ihead.ConfigStruct = null;      /// Clear previous ConfigStruct, avoid reuse of (not anymore valid) PCB Number
+
 			if (OpenPort(threadId, ihead) != 0) return CommErr.OpenPort;   /// Open RFID port
 
             CommErr error = CommErr.Read;
@@ -847,7 +849,7 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication
 		/// <returns>true on success</returns>
         static CommErr SetTestMode(int threadId, IperlHead ihead, Results.Entities.WaterMeter wm, ref string resultStr)
         {
-            if (ihead.CommFailed) return CommErr.CommFailed;
+            if (ihead.CommFailed || ihead.ConfigStruct == null) return CommErr.CommFailed;
 			
             Byte testModeConfig = 0xA0;                 /// Default value
             ///
diff --git a/TestBenchFramework/Properties/AssemblyInfo.cs b/TestBenchFramework/Properties/AssemblyInfo.cs
index 17a61d2e7..2a2a5fcd1 100644
--- a/TestBenchFramework/Properties/AssemblyInfo.cs
+++ b/TestBenchFramework/Properties/AssemblyInfo.cs
@@ -29,5 +29,5 @@ using System.Runtime.InteropServices;
 //      Build Number
 //      Revision
 //
-[assembly: AssemblyVersion("2.17.752.0")]
-[assembly: AssemblyFileVersion("2.17.752.0")]
+[assembly: AssemblyVersion("2.17.753.0")]
+[assembly: AssemblyFileVersion("2.17.753.0")]