diff --git a/sink/sink20169.cfg b/sink/sink20169.cfg
index e21734d..3130de4 100644
--- a/sink/sink20169.cfg
+++ b/sink/sink20169.cfg
@@ -10,7 +10,9 @@ receivePort = 20169;
 devices = (
     {
         deviceId = "MainsCnt01";
+        // sharedSecret must have exactly 31 characters
         sharedSecret = "Uj6*uKDp@8Kvfa4g5eRMLUfVsSuqjxW";
+        // location must neither contains spaces nor commas or any other URL-special characters
         location = "Essen_DE";
     }
 );