diff --git a/edisgo/flex_opt/reinforce_grid.py b/edisgo/flex_opt/reinforce_grid.py
index 33b3a5052..25dfdebb4 100644
--- a/edisgo/flex_opt/reinforce_grid.py
+++ b/edisgo/flex_opt/reinforce_grid.py
@@ -838,17 +838,17 @@ def enhanced_reinforce_grid(
         standard line type. Should this not be sufficient to solve non-convergence
         issues, all components in the LV grid are aggregated to the MV/LV station.
         Default: False.
-    kwargs : dict
-        Keyword arguments can be all parameters of function
-        :func:`edisgo.flex_opt.reinforce_grid.reinforce_grid`, except
-        `catch_convergence_problems` which will always be set to True, `mode` which
-        is set to None, and `skip_mv_reinforcement` which will be ignored.
     separate_lv_grids : bool
         If True, all highly overloaded LV grids are separated in a first step.
     separation_threshold : int or float
         Overloading threshold for LV grid separation. If the overloading is higher than
         the threshold times the total nominal apparent power of the MV/LV transformer(s)
         the grid is separated.
+    kwargs : dict
+        Keyword arguments can be all parameters of function
+        :func:`edisgo.flex_opt.reinforce_grid.reinforce_grid`, except
+        `catch_convergence_problems` which will always be set to True, `mode` which
+        is set to None, and `skip_mv_reinforcement` which will be ignored.
 
     Returns
     -------
diff --git a/edisgo/flex_opt/reinforce_measures.py b/edisgo/flex_opt/reinforce_measures.py
index 4592e0fb3..b93e0f274 100644
--- a/edisgo/flex_opt/reinforce_measures.py
+++ b/edisgo/flex_opt/reinforce_measures.py
@@ -868,20 +868,18 @@ def add_standard_transformer(
 
         transformer_changes = {"added": {}}
 
-        transformer_s = grid.transformers_df.iloc[0]
-        new_transformer_name = transformer_s.name.split("_")
+        new_transformer_df = grid.transformers_df.iloc[[0]]
+        new_transformer_name = new_transformer_df.index[0].split("_")
         grid_id_ind = new_transformer_name.index(str(grid.id))
         new_transformer_name[grid_id_ind] = lv_grid_id_new
 
-        transformer_s.s_nom = standard_transformer.S_nom
-        transformer_s.type_info = None
-        transformer_s.r_pu = standard_transformer.r_pu
-        transformer_s.x_pu = standard_transformer.x_pu
-        transformer_s.name = "_".join([str(_) for _ in new_transformer_name])
-        transformer_s.bus0 = bus_mv
-        transformer_s.bus1 = bus_lv
-
-        new_transformer_df = transformer_s.to_frame().T
+        new_transformer_df.s_nom = standard_transformer.S_nom
+        new_transformer_df.type_info = None
+        new_transformer_df.r_pu = standard_transformer.r_pu
+        new_transformer_df.x_pu = standard_transformer.x_pu
+        new_transformer_df.index = ["_".join([str(_) for _ in new_transformer_name])]
+        new_transformer_df.bus0 = bus_mv
+        new_transformer_df.bus1 = bus_lv
 
         old_s_nom = grid.transformers_df.s_nom.sum()