diff --git a/src/service/service/tools/OpticalTools.py b/src/service/service/tools/OpticalTools.py
index 20cd6b42a17b0f41f3aee20fec82727902ae0ef1..ad2f8cbeca0edbb6511c1b0ee1aec70183a806ca 100644
--- a/src/service/service/tools/OpticalTools.py
+++ b/src/service/service/tools/OpticalTools.py
@@ -39,7 +39,7 @@ VAR_NAME_OPTICAL_CTRL_SCHEMA       = get_optical_controller_setting('SCHEMA')
 VAR_NAME_OPTICAL_CTRL_HOST         = get_optical_controller_setting(ENVVAR_SUFIX_SERVICE_HOST)
 VAR_NAME_OPTICAL_CTRL_PORT         = get_optical_controller_setting(ENVVAR_SUFIX_SERVICE_PORT_GRPC)
 
-OPTICAL_CTRL_BASE_URL = '{:s}://{:s}:{:s}/OpticalTFS'
+OPTICAL_CTRL_BASE_URL = '{:s}://{:s}:{:d}/OpticalTFS'
 
 def get_optical_controller_base_url() -> str:
     settings = find_environment_variables([