diff --git a/tangostationcontrol/tangostationcontrol/test/clients/test_client.py b/tangostationcontrol/tangostationcontrol/test/clients/test_client.py
index ea03e850d4021d0d4c40e82a60d4fd1f0a9d67ea..577bab69e469fb26af2252790b22f7f92d2c0ade 100644
--- a/tangostationcontrol/tangostationcontrol/test/clients/test_client.py
+++ b/tangostationcontrol/tangostationcontrol/test/clients/test_client.py
@@ -73,8 +73,12 @@ class test_client(CommClient):
         """
         takes all gathered data to configure and return the correct read and write functions
         """
-
-        self.value = numpy.zeros(dims, dtype)
+        if dtype == str and dims == (1,):
+            self.value = ''
+        elif dims == (1,):
+            self.value = dtype(0)
+        else:
+            self.value = numpy.zeros(dims, dtype)
 
         def read_function():
             logger.debug("from read_function, reading {} array of type {}".format(dims, dtype))