diff --git a/src/main/java/neqsim/processSimulation/controllerDevice/ControllerDeviceBaseClass.java b/src/main/java/neqsim/processSimulation/controllerDevice/ControllerDeviceBaseClass.java
index 685eb70533..1486f94d3c 100644
--- a/src/main/java/neqsim/processSimulation/controllerDevice/ControllerDeviceBaseClass.java
+++ b/src/main/java/neqsim/processSimulation/controllerDevice/ControllerDeviceBaseClass.java
@@ -43,7 +43,9 @@ public class ControllerDeviceBaseClass extends NamedBaseClass implements Control
   private double TintValue = 0.0;
 
   /**
-   * <p>Constructor for ControllerDeviceBaseClass.</p>
+   * <p>
+   * Constructor for ControllerDeviceBaseClass.
+   * </p>
    */
   public ControllerDeviceBaseClass() {
     super("controller");
@@ -75,7 +77,8 @@ public void runTransient(double initResponse, double dt, UUID id) {
         transmitter.getMeasuredPercentValue() - (controllerSetPoint - transmitter.getMinimumValue())
             / (transmitter.getMaximumValue() - transmitter.getMinimumValue()) * 100;
 
-    TintValue += Kp / Ti * error * dt;
+    if (Ti > 0)
+      TintValue += Kp / Ti * error * dt;
     double TderivValue = Kp * Td * (error - oldError) / dt;
     response = initResponse + propConstant * (Kp * error + TintValue + TderivValue);
     // System.out.println("error " + error + " %");
diff --git a/src/main/java/neqsim/processSimulation/processEquipment/separator/Separator.java b/src/main/java/neqsim/processSimulation/processEquipment/separator/Separator.java
index e3ababd76a..d55243358b 100644
--- a/src/main/java/neqsim/processSimulation/processEquipment/separator/Separator.java
+++ b/src/main/java/neqsim/processSimulation/processEquipment/separator/Separator.java
@@ -244,47 +244,52 @@ public void run(UUID id) {
       liquidOutStream.getFluid().init(3);
     }
     // liquidOutStream.setThermoSystemFromPhase(thermoSystem2, "aqueous");
-    try {
-      thermoSystem = thermoSystem2.clone();
-      thermoSystem.setTotalNumberOfMoles(1.0e-10);
-      thermoSystem.init(1);
-      // System.out.println("number of phases " + thermoSystem.getNumberOfPhases());
-      double totalliquidVolume = 0.0;
-      for (int j = 0; j < thermoSystem.getNumberOfPhases(); j++) {
-        double relFact = gasVolume / (thermoSystem2.getPhase(j).getVolume() * 1.0e-5);
-        if (j >= 1) {
-          relFact = liquidVolume / (thermoSystem2.getPhase(j).getVolume() * 1.0e-5);
-
-          totalliquidVolume += liquidVolume / thermoSystem2.getPhase(j).getMolarVolume();
-        }
-        for (int i = 0; i < thermoSystem.getPhase(j).getNumberOfComponents(); i++) {
-          thermoSystem.addComponent(thermoSystem.getPhase(j).getComponent(i).getComponentNumber(),
-              relFact * thermoSystem2.getPhase(j).getComponent(i).getNumberOfMolesInPhase(), j);
+    if (getCalculateSteadyState()) {
+      thermoSystem = thermoSystem2;
+    } else {
+      try {
+        thermoSystem = thermoSystem2.clone();
+        // thermoSystem.setTotalNumberOfMoles(1.0);
+        thermoSystem.init(1);
+        // System.out.println("number of phases " + thermoSystem.getNumberOfPhases());
+        double totalliquidVolume = 0.0;
+        for (int j = 0; j < thermoSystem.getNumberOfPhases(); j++) {
+          double relFact = gasVolume / (thermoSystem2.getPhase(j).getVolume("m3"));
+          if (j >= 1) {
+            relFact = liquidVolume / (thermoSystem2.getPhase(j).getVolume("m3"));
+
+            totalliquidVolume += liquidVolume / thermoSystem2.getPhase(j).getMolarVolume();
+          }
+
+          for (int i = 0; i < thermoSystem.getPhase(j).getNumberOfComponents(); i++) {
+            thermoSystem.addComponent(i, Math.signum(relFact - 1.0) * relFact
+                * thermoSystem2.getPhase(j).getComponent(i).getNumberOfMolesInPhase(), j);
+          }
         }
-      }
 
-      if (thermoSystem.hasPhaseType("gas")) {
-        thermoSystem.setBeta(gasVolume / thermoSystem2.getPhase(0).getMolarVolume()
-            / (gasVolume / thermoSystem2.getPhase(0).getMolarVolume() + totalliquidVolume));
+        if (thermoSystem.hasPhaseType("gas")) {
+          thermoSystem.setBeta(gasVolume / thermoSystem2.getPhase(0).getMolarVolume()
+              / (gasVolume / thermoSystem2.getPhase(0).getMolarVolume() + totalliquidVolume));
+        }
+        thermoSystem.initBeta();
+        thermoSystem.init(3);
+        // System.out.println("moles in separator " + thermoSystem.getNumberOfMoles());
+        // double volume1 = thermoSystem.getVolume();
+        // System.out.println("volume1 bef " + volume1);
+        // System.out.println("beta " + thermoSystem.getBeta());
+
+        liquidLevel = thermoSystem.getPhase(1).getVolume("m3") / (liquidVolume + gasVolume);
+        liquidVolume = getLiquidLevel() * 3.14 / 4.0 * getInternalDiameter() * getInternalDiameter()
+            * getSeparatorLength();
+        gasVolume = (1.0 - getLiquidLevel()) * 3.14 / 4.0 * getInternalDiameter()
+            * getInternalDiameter() * getSeparatorLength();
+        // System.out.println("moles out" +
+        // liquidOutStream.getThermoSystem().getTotalNumberOfMoles());
+      } catch (Exception ex) {
+        logger.error(ex.getMessage(), ex);
       }
-      thermoSystem.initBeta();
-      thermoSystem.init(3);
-      // System.out.println("moles in separator " + thermoSystem.getNumberOfMoles());
-      // double volume1 = thermoSystem.getVolume();
-      // System.out.println("volume1 bef " + volume1);
-      // System.out.println("beta " + thermoSystem.getBeta());
-
-      liquidLevel = thermoSystem.getPhase(1).getVolume() * 1e-5 / (liquidVolume + gasVolume);
-      liquidVolume = getLiquidLevel() * 3.14 / 4.0 * getInternalDiameter() * getInternalDiameter()
-          * getSeparatorLength();
-      gasVolume = (1.0 - getLiquidLevel()) * 3.14 / 4.0 * getInternalDiameter()
-          * getInternalDiameter() * getSeparatorLength();
-      // System.out.println("moles out" +
-      // liquidOutStream.getThermoSystem().getTotalNumberOfMoles());
-    } catch (Exception ex) {
-      logger.error(ex.getMessage(), ex);
     }
-    thermoSystem = thermoSystem2;
+    // thermoSystem = thermoSystem2;
     setCalculationIdentifier(id);
   }
 
@@ -307,49 +312,44 @@ public void runTransient(double dt, UUID id) {
       run(id);
       increaseTime(dt);
       return;
-    }
+    } else {
+      inletStreamMixer.run(id);
+      thermoSystem.init(3);
+      gasOutStream.getThermoSystem().init(3);
+      liquidOutStream.getThermoSystem().init(3);
+      double volume1 = thermoSystem.getVolume("m3");
+      // System.out.println("volume " + volume1);
+      double deltaEnergy = inletStreamMixer.getOutletStream().getThermoSystem().getEnthalpy()
+          - gasOutStream.getThermoSystem().getEnthalpy()
+          - liquidOutStream.getThermoSystem().getEnthalpy();
+      // System.out.println("enthalph delta " + deltaEnergy);
+      double newEnergy = thermoSystem.getInternalEnergy() + dt * deltaEnergy;
+      for (int i = 0; i < thermoSystem.getPhase(0).getNumberOfComponents(); i++) {
+        double dn = inletStreamMixer.getOutletStream().getThermoSystem().getPhase(0).getComponent(i)
+            .getNumberOfMolesInPhase()
+            + inletStreamMixer.getOutletStream().getThermoSystem().getPhase(1).getComponent(i)
+                .getNumberOfMolesInPhase()
+            - gasOutStream.getThermoSystem().getPhase(0).getComponent(i).getNumberOfMolesInPhase()
+            - liquidOutStream.getThermoSystem().getPhase(0).getComponent(i)
+                .getNumberOfMolesInPhase();
+        // System.out.println("dn " + dn);
+        thermoSystem.addComponent(inletStreamMixer.getOutletStream().getThermoSystem().getPhase(0)
+            .getComponent(i).getComponentNumber(), dn * dt);
+      }
+      ThermodynamicOperations thermoOps = new ThermodynamicOperations(thermoSystem);
+      thermoOps.VUflash(volume1, newEnergy, "m3", "J");
 
-    inletStreamMixer.run(id);
+      setTempPres(thermoSystem.getTemperature(), thermoSystem.getPressure());
 
-    // System.out.println("moles out" +
-    // liquidOutStream.getThermoSystem().getTotalNumberOfMoles());
-    // double inMoles =
-    // inletStreamMixer.getOutStream().getThermoSystem().getTotalNumberOfMoles();
-    // double gasoutMoles = gasOutStream.getThermoSystem().getNumberOfMoles();
-    // double liqoutMoles = liquidOutStream.getThermoSystem().getNumberOfMoles();
-    thermoSystem.init(3);
-    gasOutStream.getThermoSystem().init(3);
-    liquidOutStream.getThermoSystem().init(3);
-    double volume1 = thermoSystem.getVolume();
-    // System.out.println("volume1 " + volume1);
-    double deltaEnergy = inletStreamMixer.getOutletStream().getThermoSystem().getEnthalpy()
-        - gasOutStream.getThermoSystem().getEnthalpy()
-        - liquidOutStream.getThermoSystem().getEnthalpy();
-    // System.out.println("enthalph delta " + deltaEnergy);
-    double newEnergy = thermoSystem.getInternalEnergy() + dt * deltaEnergy;
-    for (int i = 0; i < thermoSystem.getPhase(0).getNumberOfComponents(); i++) {
-      double dn = inletStreamMixer.getOutletStream().getThermoSystem().getPhase(0).getComponent(i)
-          .getNumberOfMolesInPhase()
-          + inletStreamMixer.getOutletStream().getThermoSystem().getPhase(1).getComponent(i)
-              .getNumberOfMolesInPhase()
-          - gasOutStream.getThermoSystem().getPhase(0).getComponent(i).getNumberOfMolesInPhase()
-          - liquidOutStream.getThermoSystem().getPhase(0).getComponent(i).getNumberOfMolesInPhase();
-      // System.out.println("dn " + dn);
-      thermoSystem.addComponent(inletStreamMixer.getOutletStream().getThermoSystem().getPhase(0)
-          .getComponent(i).getComponentNumber(), dn * dt);
+      liquidLevel = thermoSystem.getPhase(1).getVolume("m3") / (liquidVolume + gasVolume);
+      // System.out.println("liquid level " + liquidLevel);
+      liquidVolume = getLiquidLevel() * 3.14 / 4.0 * getInternalDiameter() * getInternalDiameter()
+          * getSeparatorLength();
+      // System.out.println("gasvol " + gasVolume + " liqvol " + liquidVolume);
+      gasVolume = (1.0 - getLiquidLevel()) * 3.14 / 4.0 * getInternalDiameter()
+          * getInternalDiameter() * getSeparatorLength();
+      setCalculationIdentifier(id);
     }
-    ThermodynamicOperations thermoOps = new ThermodynamicOperations(thermoSystem);
-    thermoOps.VUflash(volume1, newEnergy);
-
-    setTempPres(thermoSystem.getTemperature(), thermoSystem.getPressure());
-
-    liquidLevel = thermoSystem.getPhase(1).getVolume() * 1e-5 / (liquidVolume + gasVolume);
-    // System.out.println("liquid level " + liquidLevel);
-    liquidVolume = getLiquidLevel() * 3.14 / 4.0 * getInternalDiameter() * getInternalDiameter()
-        * getSeparatorLength();
-    gasVolume = (1.0 - getLiquidLevel()) * 3.14 / 4.0 * getInternalDiameter()
-        * getInternalDiameter() * getSeparatorLength();
-    setCalculationIdentifier(id);
   }
 
   /**
@@ -499,7 +499,7 @@ public void setInternalDiameter(double diameter) {
    * @return a double
    */
   public double getGasSuperficialVelocity() {
-    return thermoSystem.getPhase(0).getTotalVolume() / 1e5
+    return thermoSystem.getPhase(0).getVolume("m3")
         / (neqsim.thermo.ThermodynamicConstantsInterface.pi * getInternalDiameter()
             * getInternalDiameter() / 4.0);
   }
@@ -554,7 +554,7 @@ public double getDeRatedGasLoadFactor() {
     if (surfaceTension < 10.0e-3) {
       derating = 1.0 - 0.5 * (10.0e-3 - surfaceTension) / 10.0e-3;
     }
-    System.out.println("derating " + derating);
+    // System.out.println("derating " + derating);
     double term1 = (thermoSystem.getPhase(1).getPhysicalProperties().getDensity()
         - thermoSystem.getPhase(0).getPhysicalProperties().getDensity())
         / thermoSystem.getPhase(0).getPhysicalProperties().getDensity();
@@ -577,7 +577,7 @@ public double getDeRatedGasLoadFactor(int phase) {
     if (surfaceTension < 10.0e-3) {
       derating = 1.0 - 0.5 * (10.0e-3 - surfaceTension) / 10.0e-3;
     }
-    System.out.println("derating " + derating);
+    // System.out.println("derating " + derating);
     double term1 = (thermoSystem.getPhase(phase).getPhysicalProperties().getDensity()
         - thermoSystem.getPhase(0).getPhysicalProperties().getDensity())
         / thermoSystem.getPhase(0).getPhysicalProperties().getDensity();
@@ -658,7 +658,7 @@ public SeparatorSection getSeparatorSection(String name) {
         return sec;
       }
     }
-    System.out.println("no section with name: " + name + " found.....");
+    // System.out.println("no section with name: " + name + " found.....");
     return null;
   }
 
diff --git a/src/main/java/neqsim/processSimulation/processSystem/ProcessSystem.java b/src/main/java/neqsim/processSimulation/processSystem/ProcessSystem.java
index c32529e658..c63a5a38f9 100644
--- a/src/main/java/neqsim/processSimulation/processSystem/ProcessSystem.java
+++ b/src/main/java/neqsim/processSimulation/processSystem/ProcessSystem.java
@@ -33,7 +33,7 @@ public class ProcessSystem extends SimulationBaseClass {
   static Logger logger = LogManager.getLogger(ProcessSystem.class);
 
   transient Thread thisThread;
-  String[][] signalDB = new String[1000][100];
+  String[][] signalDB = new String[10000][100];
   private double surroundingTemperature = 288.15;
   private int timeStepNumber = 0;
   private ArrayList<ProcessEquipmentInterface> unitOperations =
diff --git a/src/test/java/neqsim/processSimulation/processSystem/ProcessSystemRunTransientTest.java b/src/test/java/neqsim/processSimulation/processSystem/ProcessSystemRunTransientTest.java
index 32d6053ad2..4bcc10f26f 100644
--- a/src/test/java/neqsim/processSimulation/processSystem/ProcessSystemRunTransientTest.java
+++ b/src/test/java/neqsim/processSimulation/processSystem/ProcessSystemRunTransientTest.java
@@ -31,12 +31,10 @@ public void testGetName() {
   }
 
   @Test
-  void testGetTime() {
-  }
+  void testGetTime() {}
 
   @Test
-  void testGetTimeStep() {
-  }
+  void testGetTimeStep() {}
 
   private SystemInterface getTestSystem() {
     neqsim.thermo.system.SystemInterface testSystem =
@@ -49,7 +47,7 @@ private SystemInterface getTestSystem() {
     return testSystem;
   }
 
-  // @Test
+  @Test
   public void testDynamicCalculation() {
     neqsim.thermo.system.SystemInterface testSystem = getTestSystem();
 
@@ -59,7 +57,7 @@ public void testDynamicCalculation() {
 
     ThrottlingValve valve1 = new ThrottlingValve("valve_1", stream1);
     valve1.setOutletPressure(5.0);
-    valve1.setPercentValveOpening(50);
+    valve1.setPercentValveOpening(40);
 
     Separator separator1 = new Separator("sep 1");
     separator1.addStream(valve1.getOutletStream());
@@ -81,7 +79,7 @@ public void testDynamicCalculation() {
     flowController.setTransmitter(flowTransmitter);
     flowController.setReverseActing(true);
     flowController.setControllerSetPoint(63.5);
-    flowController.setControllerParameters(0.1, 0.10, 0.0);
+    flowController.setControllerParameters(1.2, 100.0, 0.0);
 
     p.add(stream1);
     p.add(valve1);
@@ -90,15 +88,16 @@ public void testDynamicCalculation() {
     p.add(valve3);
     p.add(flowTransmitter);
     valve1.setController(flowController);
+    valve1.setCalculateSteadyState(false);
 
     p.run();
 
     // transient behaviour
     p.setTimeStep(1.0);
-    for (int i = 0; i < 5; i++) {
-      // logger.info("volume flow " + flowTransmitter.getMeasuredValue()
-      // + " valve opening " + valve_1.getPercentValveOpening() + " pressure "
-      // + separator_1.getGasOutStream().getPressure());
+    for (int i = 0; i < 50; i++) {
+      System.out.println("volume flow " + flowTransmitter.getMeasuredValue() + " valve opening "
+          + valve1.getPercentValveOpening() + " pressure "
+          + separator1.getGasOutStream().getPressure());
       p.runTransient();
       for (SimulationInterface sim : p.getUnitOperations()) {
         assertEquals(sim.getCalculationIdentifier(), p.getCalculationIdentifier());
@@ -111,49 +110,62 @@ public void testDynamicCalculation2() {
     neqsim.thermo.system.SystemInterface testSystem2 =
         new neqsim.thermo.system.SystemSrkEos((273.15 + 25.0), 10.00);
     testSystem2.addComponent("methane", 1.1);
-    testSystem2.addComponent("ethane", 0.10001);
     testSystem2.addComponent("n-heptane", 1.001);
     testSystem2.setMixingRule(2);
 
-    Stream purgeStream = new Stream("Purge Stream", testSystem2);
-    ThrottlingValve purgeValve = new ThrottlingValve("purgeValve", purgeStream);
-    purgeValve.setOutletPressure(7.0);
-    purgeValve.setPercentValveOpening(50.0);
+    neqsim.thermo.system.SystemInterface testSystem3 =
+        new neqsim.thermo.system.SystemSrkEos((273.15 + 25.0), 10.00);
+    testSystem3.addComponent("methane", 1.1);
+    testSystem3.addComponent("n-heptane", 0.001);
+    testSystem3.setMixingRule(2);
+
+    Stream stream1 = new Stream("Stream1", testSystem2);
+    stream1.setFlowRate(1000.0, "kg/hr");
+    stream1.setPressure(10.0, "bara");
+    stream1.setTemperature(25.0, "C");
+
+    Stream streamPurge = new Stream("StreamPurge", testSystem3);
+    streamPurge.setFlowRate(5.0, "kg/hr");
+    streamPurge.setPressure(10.0, "bara");
+    streamPurge.setTemperature(25.0, "C");
 
-    neqsim.thermo.system.SystemInterface testSystem = getTestSystem();
-    Stream stream1 = new Stream("Stream1", testSystem);
-    stream1.setCalculateSteadyState(false);
     ThrottlingValve valve1 = new ThrottlingValve("valve_1", stream1);
     valve1.setOutletPressure(7.0);
     valve1.setPercentValveOpening(50);
+    valve1.setCalculateSteadyState(false);
+
+    ThrottlingValve valvePurge = new ThrottlingValve("valve_purge", streamPurge);
+    valvePurge.setOutletPressure(7.0);
+    valvePurge.setPercentValveOpening(50);
+    valvePurge.setCalculateSteadyState(false);
 
     Separator separator1 = new Separator("separator_1");
     separator1.addStream(valve1.getOutletStream());
-    separator1.addStream(purgeValve.getOutletStream());
-    separator1.setCalculateSteadyState(true);
+    separator1.addStream(valvePurge.getOutletStream());
+    separator1.setCalculateSteadyState(false);
+    separator1.setSeparatorLength(3.0);
+    separator1.setInternalDiameter(0.8);
 
     ThrottlingValve valve2 = new ThrottlingValve("valve_2", separator1.getLiquidOutStream());
-    valve2.setOutletPressure(5.0);
+    valve2.setOutletPressure(1.0);
     valve2.setPercentValveOpening(50);
-    valve2.setCalculateSteadyState(true);
-    // valve_2.setCv(10.0);
+    valve2.setCalculateSteadyState(false);
 
     ThrottlingValve valve3 = new ThrottlingValve("valve_3", separator1.getGasOutStream());
-    valve3.setOutletPressure(5.0);
+    valve3.setOutletPressure(1.0);
     valve3.setPercentValveOpening(50);
-    valve3.setCalculateSteadyState(true);
-    // valve_3.setCv(10.0);
+    valve3.setCalculateSteadyState(false);
 
     LevelTransmitter separatorLevelTransmitter = new LevelTransmitter(separator1);
     separatorLevelTransmitter.setName("separatorLevelTransmitter1");
-    separatorLevelTransmitter.setMaximumValue(1.0);
-    separatorLevelTransmitter.setMinimumValue(0.0);
+    separatorLevelTransmitter.setMaximumValue(0.5);
+    separatorLevelTransmitter.setMinimumValue(0.2);
 
     ControllerDeviceInterface separatorLevelController = new ControllerDeviceBaseClass();
-    separatorLevelController.setReverseActing(true);
+    separatorLevelController.setReverseActing(false);
     separatorLevelController.setTransmitter(separatorLevelTransmitter);
     separatorLevelController.setControllerSetPoint(0.3);
-    separatorLevelController.setControllerParameters(1, 1000.0, 0.0);
+    separatorLevelController.setControllerParameters(0.510, 200.0, 0.0);
 
     PressureTransmitter separatorPressureTransmitter =
         new PressureTransmitter(separator1.getGasOutStream());
@@ -165,13 +177,12 @@ public void testDynamicCalculation2() {
     separatorPressureController.setTransmitter(separatorPressureTransmitter);
     separatorPressureController.setReverseActing(false);
     separatorPressureController.setControllerSetPoint(7.0);
-    separatorPressureController.setControllerParameters(0.5, 10.0, 0.0);
+    separatorPressureController.setControllerParameters(1.5, .0, 0.0);
 
     p.add(stream1);
+    p.add(streamPurge);
     p.add(valve1);
-
-    p.add(purgeStream);
-    p.add(purgeValve);
+    p.add(valvePurge);
     p.add(separator1);
     p.add(valve2);
     p.add(valve3);
@@ -189,26 +200,17 @@ public void testDynamicCalculation2() {
     }
 
     // p.displayResult();
-    p.setTimeStep(0.01);
-    for (int i = 0; i < 500; i++) {
-      // logger.info("pressure "+separator_1.getGasOutStream().getPressure()+ " flow "+
-      // separator_1.getGasOutStream().getFlowRate("kg/hr") + " sepr height
-      // "+separatorLevelTransmitter.getMeasuredValue());
+    p.setTimeStep(1.0);
+    for (int i = 0; i < 9000; i++) {
+      System.out.println("pressure " + separator1.getGasOutStream().getPressure() + " flow "
+          + separator1.getGasOutStream().getFlowRate("kg/hr") + " sepr height "
+          + separatorLevelTransmitter.getMeasuredValue() + "valve2 opening "
+          + valve2.getPercentValveOpening() + "valve3 opening " + valve3.getPercentValveOpening());
       p.runTransient();
       for (SimulationInterface sim : p.getUnitOperations()) {
         assertEquals(p.getCalculationIdentifier(), sim.getCalculationIdentifier());
       }
     }
 
-    valve1.setPercentValveOpening(60);
-
-    for (int i = 0; i < 10; i++) {
-      // logger.info("pressure "+separator_1.getGasOutStream().getPressure()+ " flow "+
-      // separator_1.getGasOutStream().getFlowRate("kg/hr"));
-      p.runTransient();
-      for (SimulationInterface sim : p.getUnitOperations()) {
-        assertEquals(p.getCalculationIdentifier(), sim.getCalculationIdentifier());
-      }
-    }
   }
 }