diff --git a/devices/devices/sdp/statistics.py b/devices/devices/sdp/statistics.py
index 956dbc9b5ab37bbbb0d2fed50273f49cdb9fea5e..2a9ddb9ec91e8f3bd55ef2d2d2fed50e1b637c9f 100644
--- a/devices/devices/sdp/statistics.py
+++ b/devices/devices/sdp/statistics.py
@@ -129,8 +129,10 @@ class Statistics(hardware_device, metaclass=ABCMeta):
             try:
                 if i.comms_id == StatisticsClient:
                     i.set_comm_client(self.statistics_client)
-                if i.comms_id == OPCUAConnection:
+                elif i.comms_id == OPCUAConnection:
                     i.set_comm_client(self.OPCUA_client)
+                else:
+                    raise ValueError("Cannot set comm client for attribute {}: Unknown comms_id {}".format(i, i.comms_id))
             except Exception as e:
                 # use the pass function instead of setting read/write fails
                 i.set_pass_func()