diff --git a/TestBenchFramework/BenchControl/Elde/Valve/SetValvesOp.cs b/TestBenchFramework/BenchControl/Elde/Valve/SetValvesOp.cs
index 2978c2f85..4650e32cb 100644
--- a/TestBenchFramework/BenchControl/Elde/Valve/SetValvesOp.cs
+++ b/TestBenchFramework/BenchControl/Elde/Valve/SetValvesOp.cs
@@ -14,18 +14,38 @@ namespace TBF.BenchControl.Elde.Valve
 
 		class SwitchPoint
 		{
-			public int TimeSec;             /// Time [s]
-			public IList<IValve> VOpen;     /// List of valves to open in this point of time
-			public IList<IValve> VClose;    /// List of valves to close in this point of time
+			public int TimeSec;             /// Relative time in [s] from the start of the operation
+            public IList<IValve> VOpen;     /// List of valves to open in this point of time
+            public IList<IValve> VClose;    /// List of valves to close in this point of time
 			public ulong MasksOpen;         /// OR-ed bitmasks of valves to open in this point of time
             public ulong MasksClose;        /// OR-ed bitmasks of valves to close in this point of time
-            public int MaxDelay;            /// Max. delay in [s] of all valves to be opened or closed
+
+            public SwitchPoint(int time, IList<IValve> vOpen, IList<IValve> vClose)
+            {
+                this.TimeSec = time;
+                this.VOpen  = (vOpen == null) ? new List<IValve>() : vOpen;
+                this.VClose = (vClose == null) ? new List<IValve>() : vClose;
+            }
+
+            /// Max. delay in [s] of all valves to be opened or closed 
+            public int MaxDelay
+            {
+                get
+                {
+                    int max = 0;
+                    foreach (var vlv in VOpen)  if (vlv.Delay > max) max = vlv.Delay;
+                    foreach (var vlv in VClose) if (vlv.Delay > max) max = vlv.Delay;
+                    return max;
+                }
+            }
 		}
 
 		IList<SwitchPoint> switchPointsRaw;
 		IList<SwitchPoint> switchPoints;
 		int nextIx;
 		int swStartTime;
+        int maxDelayTime;                   /// Max. delay from all valve/pump switches.
+                                            /// Relative time in [s] from the start of the operation
 
 		/// <summary>
 		/// Processes coupled valves and creates switch points.
@@ -36,7 +56,7 @@ namespace TBF.BenchControl.Elde.Valve
 		IList<SwitchPoint> CollectSwitchPoints(IList<IValve> valvesOpen, IList<IValve> valvesClose)
 		{
 			IList<SwitchPoint> result = new List<SwitchPoint>();
-			result.Add(new SwitchPoint { TimeSec = 0, VOpen = valvesOpen, VClose = valvesClose });
+			result.Add(new SwitchPoint(0, valvesOpen, valvesClose));
 
 			foreach (var valve in StateMachine.CoupledValves)
 			{
@@ -51,9 +71,7 @@ namespace TBF.BenchControl.Elde.Valve
 					}
 					else
 					{
-						result.Add(new SwitchPoint { TimeSec = time,
-													 VOpen = ValveBase.MakeList(valve),
-													 VClose = new List<IValve>() });
+						result.Add(new SwitchPoint(time, ValveBase.MakeList(valve), null));
 					}
 				}
 				else if ((!valve.InvertCouple && valvesClose.Contains(valve.CoupledTo)) ||
@@ -67,9 +85,7 @@ namespace TBF.BenchControl.Elde.Valve
 					}
 					else
 					{
-						result.Add(new SwitchPoint { TimeSec = time,
-													 VOpen = new List<IValve>(),
-													 VClose = ValveBase.MakeList(valve) });
+						result.Add(new SwitchPoint(time, null, ValveBase.MakeList(valve)));
 					}
 				}
 			}
@@ -169,7 +185,8 @@ namespace TBF.BenchControl.Elde.Valve
         {
 			controlBoard.SetValves(switchPoints[0].MasksOpen, switchPoints[0].MasksClose);
 			swStartTime = StateMachine.Time;
-			nextIx = 1;
+            maxDelayTime = switchPoints[0].MaxDelay;
+            nextIx = 1;
 		}
 
 		/// <summary>Run this operation</summary>
@@ -178,13 +195,22 @@ namespace TBF.BenchControl.Elde.Valve
 		/// </returns>
 		public Event Run()
 		{
-			if (nextIx >= switchPoints.Count) return Event.ValvesSet;
+            if (nextIx >= switchPoints.Count)
+            {
+                if (StateMachine.Time >= swStartTime + maxDelayTime) return Event.ValvesSet;
+                else                                                 return Event.None;
+            }
 			
 			if (StateMachine.Time >= swStartTime + switchPoints[nextIx].TimeSec)
 			{
-				controlBoard.SetValves(switchPoints[nextIx].MasksOpen, switchPoints[nextIx].MasksClose);
-				nextIx++;
+                if (switchPoints[nextIx].TimeSec + switchPoints[nextIx].MaxDelay > maxDelayTime)
+                {
+                    maxDelayTime = switchPoints[nextIx].TimeSec + switchPoints[nextIx].MaxDelay;
+                }
+                controlBoard.SetValves(switchPoints[nextIx].MasksOpen, switchPoints[nextIx].MasksClose);
+                nextIx++;
 			}
+
 			return Event.None;
 		}