diff --git a/custom_components/myhome/validate.py b/custom_components/myhome/validate.py
index a27b09c..24bf064 100644
--- a/custom_components/myhome/validate.py
+++ b/custom_components/myhome/validate.py
@@ -161,7 +161,7 @@ def __init__(self, msg=None):
         self.msg = msg
 
     def __call__(self, v):
-        if type(v) == str and v.isdigit() and len(v) == 2:
+        if type(v) == str and v.isdigit() and len(v) == 1:
             if int(v) > 15:
                 raise Invalid(f"Invalid Bus Interface number {v}, it must be between 00 and 15.")
         elif v is not None: