diff --git a/src/de/ctdo/crashtest/domotics/IRelaisboard.java b/src/de/ctdo/crashtest/domotics/IRelaisboard.java
index a5873de..2c78b4e 100644
--- a/src/de/ctdo/crashtest/domotics/IRelaisboard.java
+++ b/src/de/ctdo/crashtest/domotics/IRelaisboard.java
@@ -5,6 +5,6 @@ public interface IRelaisboard {
     void toggleRelais(final int relais, final int milliseconds);
     void blinkRelais(final int relais, final int pause);
     void blinkRelaisStop(final int relais);
-    boolean open();
+    void open();
     void close();
 }
diff --git a/src/de/ctdo/crashtest/domotics/Relaisboard.java b/src/de/ctdo/crashtest/domotics/Relaisboard.java
index 99170d6..7984c3a 100644
--- a/src/de/ctdo/crashtest/domotics/Relaisboard.java
+++ b/src/de/ctdo/crashtest/domotics/Relaisboard.java
@@ -45,13 +45,13 @@ public class Relaisboard implements IRelaisboard {
 
 
     @Override
-    public boolean open() {
+    public void open() {
         serialPortGeoeffnet = false;
         Boolean foundPort = false;
 
         if (serialPortGeoeffnet) {
             Logger.sLog("Serialport bereits geöffnet");
-            return false;
+            return;
         }
 
         Enumeration enumComm = CommPortIdentifier.getPortIdentifiers();
@@ -66,7 +66,7 @@ public class Relaisboard implements IRelaisboard {
         }
         if (!foundPort) {
             Logger.sLog("Serialport nicht gefunden: " + portName);
-            return false;
+            return;
         }
 
         try {
@@ -77,8 +77,6 @@ public class Relaisboard implements IRelaisboard {
 
             outputStream = serialPort.getOutputStream();
             serialPortGeoeffnet = true;
-
-            return true;
         } catch (PortInUseException e) {
             Logger.sLog("Relaisboard error: Port belegt " + portName);
         } catch (IOException e) {
@@ -86,8 +84,6 @@ public class Relaisboard implements IRelaisboard {
         } catch(UnsupportedCommOperationException e) {
             Logger.sLog("Relaisboard error: Konnte Schnittstellen-Paramter nicht setzen");
         }
-
-        return false;
     }
 
     @Override