diff --git a/devices/clients/opcua_connection.py b/devices/clients/opcua_connection.py
index 6b4a5b8221ca46bd150487d681c6b0ec63699fd9..c5fa45507afc60dedb21c2d972861acedee827de 100644
--- a/devices/clients/opcua_connection.py
+++ b/devices/clients/opcua_connection.py
@@ -90,7 +90,7 @@ class OPCUAConnection(CommClient):
 		try:
 			self.client.disconnect()
 		except Exception as e:
-			self.streams.error_stream("Disconnect from OPC-UA server %s failed: %s", self._servername(), e)
+			self.streams.error_stream("Disconnect from OPC-UA server {} failed: {}".format(self._servername(), e))
 
 	def ping(self):
 		"""
@@ -99,7 +99,7 @@ class OPCUAConnection(CommClient):
 		try:
 			self.client.send_hello()
 		except Exception as e:
-			raise Exception("Lost connection to server %s: %s", self._servername(), e)
+			raise Exception("Lost connection to server {}.".format(self._servername())) from e
 
 	def _setup_annotation(self, annotation):
 		"""
@@ -115,13 +115,12 @@ class OPCUAConnection(CommClient):
 		elif isinstance(annotation, list):
 			path = annotation
 		else:
-			raise Exception("OPC-ua mapping requires either a list of the path or dict with the path. Was given %s type containing: %s", type(annotation), annotation)
+			raise Exception("OPC-ua mapping requires either a list of the path or dict with the path. Was given {} type containing: {}".format(type(annotation), annotation))
 
 		try:
 			node = self.obj.get_child(path)
 		except Exception as e:
-			self.streams.error_stream("Could not get node: %s on server %s: %s", path, self._servername(), e)
-			raise Exception("Could not get node: %s on server %s", path, self._servername()) from e
+			raise Exception("Could not get node: {} on server {}".format(path, self._servername())) from e
 
 		return node