diff --git a/src/bitsea/Float/dump_index.py b/src/bitsea/Float/dump_index.py
index 13ffa6c3..b50a907b 100644
--- a/src/bitsea/Float/dump_index.py
+++ b/src/bitsea/Float/dump_index.py
@@ -97,7 +97,7 @@ def file_header_content(filename,VARLIST, avail_params=None):
         ncIN.close()
         return
 
-    ref  = np.array(ncIN.variables['REFERENCE_DATE_TIME']).tobytes().decode()
+    ref  = np.asarray(ncIN.variables['REFERENCE_DATE_TIME']).tobytes().decode()
     juld = int (ncIN.variables['JULD'][0])
     d=datetime.datetime.strptime(ref,'%Y%m%d%H%M%S')
     Time =  d+datetime.timedelta(days=juld)