diff --git a/src/rougail/convert/collect.py b/src/rougail/convert/collect.py
index 7434360e8..4cea5020a 100644
--- a/src/rougail/convert/collect.py
+++ b/src/rougail/convert/collect.py
@@ -199,6 +199,8 @@ class CollectVariable:
         new_params = []
         namespace = self.objectspace.namespace
         params_data = list(CONVERT_OPTION.get(self.user_type, {}).get("params", {}))
+        if params_data:
+            params_data.extend(["multi_length", "multi_max_length", "multi_min_length"])
         for key, val in params.items():
             if params_data and key not in params_data:
                 raise DictConsistencyError(