diff --git a/fhem/FHEM/51_I2C_BMP180.pm b/fhem/FHEM/51_I2C_BMP180.pm
index a0648627e..8a0babccd 100644
--- a/fhem/FHEM/51_I2C_BMP180.pm
+++ b/fhem/FHEM/51_I2C_BMP180.pm
@@ -132,12 +132,20 @@ sub I2C_BMP180_Init($$) {
 	$hash->{I2C_Address} = hex(BMP180_I2C_ADDRESS);
 	my $msg = '';
 	# create default attributes
-	$msg = CommandAttr(undef, $name . ' poll_interval 5');
-	$msg = CommandAttr(undef, $name . ' oversampling_settings 3');
-	if ($msg) {
-		Log3 ($hash, 1, $msg);
-		return $msg;
-	}
+	if (AttrVal($name, 'poll_interval', '?') eq '?') {  
+    	$msg = CommandAttr(undef, $name . ' poll_interval 5');
+    	if ($msg) {
+      		Log3 ($hash, 1, $msg);
+      		return $msg;
+    	}
+  }
+  if (AttrVal($name, '', '?') eq '?') {  
+    	$msg = CommandAttr(undef, $name . ' oversampling_settings 3');
+    	if ($msg) {
+      		Log3 ($hash, 1, $msg);
+      		return $msg;
+    	}
+  }
 	
 	if ($hash->{HiPi_used}) {
 		my $dev = shift @$args;
diff --git a/fhem/FHEM/52_I2C_MCP342x.pm b/fhem/FHEM/52_I2C_MCP342x.pm
index 6262dd92c..cacfb437e 100644
--- a/fhem/FHEM/52_I2C_MCP342x.pm
+++ b/fhem/FHEM/52_I2C_MCP342x.pm
@@ -113,11 +113,13 @@ sub I2C_MCP342x_Init($$) {
 
 	my $msg = '';
 	# create default attributes
-	#$msg = CommandAttr(undef, $name . ' poll_interval 5');
-	if ($msg) {
-		Log3 ($hash, 1, $msg);
-		return $msg;
-	}
+	if (AttrVal($name, 'poll_interval', '?') eq '?') {  
+    	$msg = CommandAttr(undef, $name . ' poll_interval 5');
+    	if ($msg) {
+      		Log3 ($hash, 1, $msg);
+      		return $msg;
+    	}
+  }
 	AssignIoPort($hash);	
 	$hash->{STATE} = 'Initialized';
 
@@ -158,7 +160,7 @@ sub I2C_MCP342x_Attr (@) {# hier noch Werteueberpruefung einfuegen
 			RemoveInternalTimer($hash);
 		} elsif ($val > 0) {
 			RemoveInternalTimer($hash);
-			InternalTimer(1, 'I2C_MCP23017_Poll', $hash, 0);
+			InternalTimer(1, 'I2C_MCP342x_Poll', $hash, 0);
 		} else {
 			$msg = 'Wrong poll intervall defined. poll_interval must be a number > 0';
 		} 
diff --git a/fhem/FHEM/52_I2C_SHT21.pm b/fhem/FHEM/52_I2C_SHT21.pm
index c1abd0980..2a38eaf58 100644
--- a/fhem/FHEM/52_I2C_SHT21.pm
+++ b/fhem/FHEM/52_I2C_SHT21.pm
@@ -78,11 +78,13 @@ sub I2C_SHT21_Init($$) {
 
 	my $msg = '';
 	# create default attributes
-	$msg = CommandAttr(undef, $name . ' poll_interval 5');
-	if ($msg) {
-		Log3 ($hash, 1, $msg);
-		return $msg;
-	}
+	if (AttrVal($name, 'poll_interval', '?') eq '?') {  
+    	$msg = CommandAttr(undef, $name . ' poll_interval 5');
+    	if ($msg) {
+      		Log3 ($hash, 1, $msg);
+      		return $msg;
+    	}
+  }
 	AssignIoPort($hash);	
 	$hash->{STATE} = 'Initialized';