diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 0cb6ca2..cc80ce8 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -41,7 +41,7 @@ jobs:
       - uses: "actions/setup-python@v2"
         with:
           python-version: "${{ matrix.python }}"
-      - uses: "actions/cache@v2"
+      - uses: "actions/cache@v3"
         id: "cache"
         with:
           path: "${{ env.pythonLocation }}"
diff --git a/xarray_selafin/Serafin.py b/xarray_selafin/Serafin.py
index 616fece..29b77ee 100644
--- a/xarray_selafin/Serafin.py
+++ b/xarray_selafin/Serafin.py
@@ -120,7 +120,7 @@ class SerafinHeader:
     - nb_nodes_per_elem <int>: number of nodes per element (= 3 in 2D and 6 in 3D)
     - nb_nodes_2d <int>: number of 2D nodes (equals to `nb_nodes` in 2D)
 
-    - mesh_origin <(float, float)>: x and y shift to apply to written coordinates (set by `set_mesh_origin`)
+    - mesh_origin <(int, int)>: x and y shift to apply to written coordinates (set by `set_mesh_origin`)
     - x_stored <numpy.1D-array>: east written coordinates [shape = nb_nodes]
     - y_stored <numpy.1D-array>: north written coordinates [shape = nb_nodes]
     - x <numpy.1D-array>: east coordinates [shape = nb_nodes] (set by `_compute_mesh_coordinates`)
@@ -177,7 +177,7 @@ def __init__(self, title="", format_type="SERAFIN ", lang=LANG, endian=">"):
         self.nb_nodes_per_elem = -1
         self.nb_nodes_2d = -1
 
-        self.mesh_origin = (0.0, 0.0)
+        self.mesh_origin = (0, 0)
         self.x_stored = None
         self.y_stored = None
         self.x = None
@@ -210,10 +210,10 @@ def _set_file_format_and_precision(self, file_format):
         If file format is not recognized, the file is expected to be simple precision
         """
         self.file_format = bytes(file_format, SLF_EIT).ljust(8)
-        if file_format in ("SERAFIND", "       D"):
+        if file_format in ("SERAFIND", "SELAFIND", "       D"):
             self._set_as_double_precision()
         else:
-            if file_format not in ("        ", "SERAFIN ", "SERAFINS", "SERAPHIN"):
+            if file_format not in ("SERAFIN ", "SERAFINS", "SELAFIN ", "SERAPHIN"):
                 logger.warning(
                     'Format "%s" is unknown and is forced to "SERAFIN "' % file_format
                 )
@@ -240,13 +240,13 @@ def build_params(self):
             1,
             0,
             self.mesh_origin[0],
-            self.mesh_origin[0],
+            self.mesh_origin[1],
             0,
             0,
             self.nb_planes,
-            self.nb_elements,
             0,
-            1,
+            0,
+            0 if self.date is None else 1,
         )
 
     def _build_ikle_2d(self):
@@ -803,6 +803,7 @@ def from_triangulation(self, nodes, ikle, ipobo=None):
         self._compute_mesh_coordinates()
         self.ikle = ikle.flatten()
         self._build_ikle_2d()
+        self.build_params()
         if ipobo is None:
             self.build_ipobo()
         else:
@@ -912,6 +913,9 @@ def from_file(self, file, file_size):
             file.read(4 * self.nb_nodes),
             dtype=np.dtype(np.int32).newbyteorder(self.endian),
         )
+        # A valid IPOBO should not be equal to zero array
+        if not np.any(self.ipobo):
+            logger.warning("The IPOBO array seems corrupted (zeros array). Try to rebuild it with `build_ipobo()`.")
         file.read(4)
 
         # x coordinates