diff --git a/fhem/FHEM/00_ZWDongle.pm b/fhem/FHEM/00_ZWDongle.pm
index 2033afcef..419f3d30a 100644
--- a/fhem/FHEM/00_ZWDongle.pm
+++ b/fhem/FHEM/00_ZWDongle.pm
@@ -145,7 +145,7 @@ ZWDongle_Define($$)
     return undef;
 
   } elsif($dev !~ m/@/ && $dev !~ m/:/) {
-    $def .= "\@115200";  # default baudrate
+    $dev .= "\@115200";  # default baudrate
 
   }