diff --git a/src/lmwsip/__init__.py b/src/lmwsip/__init__.py
index c43a6ab..0cda8dc 100644
--- a/src/lmwsip/__init__.py
+++ b/src/lmwsip/__init__.py
@@ -824,6 +824,32 @@ Returns:
             raise LmwCmdWarn(cmdstr, d)
         return (d[2:-1])
 
+    def cmdWrite(self, process, location, parameter, time_delta, day,
+                 time_of_day, values):
+        """Write data to LMW
+
+    process:      <WNT|VWT|AST>
+    location:     <lmw location (e.g. HOEK)>
+    parameter:    <lmw parameter (e.g. H10)>
+    time_delta:   <Time windows (max 23:59, e.g. +01:00>
+    day:          <Date>
+    time_of_day:  <Time>
+    data:         Values to be writen (e.g. 33/10;35/10).
+
+Example:
+    lmw.cmd("WNT", "HOEK", "H10", "+00:20", "13-08-2018", "16:00", "33/10;35/10")
+
+Returns:
+    The LMW answer string
+"""
+        cmdstr=process + " " + self.meetnet + "," + location + "," + \
+               parameter + "," + time_delta + "," + day + "," + \
+               time_of_day + values + "\r" 
+        d = self.sendrecv(cmdstr)
+        if (d[0] != '!'):
+            raise LmwCmdWarn(cmdstr, d)
+        return (d[2:-1])
+
     def valueStr(self, process, location, parameter, day = None,
                     time_of_day = None):
         """value(process, location, parameter, [day], [time_of_day]):
diff --git a/tests/main.py b/tests/main.py
index 508cfaf..1983f51 100755
--- a/tests/main.py
+++ b/tests/main.py
@@ -77,6 +77,10 @@ class lmwsipTest(unittest.TestCase):
         with self.assertRaises(lmwsip.LmwCmdWarn):
             self.assertEqual(type(self.sip.cmd("NOP", "DUMMY", "H10", "+00:59", "2020-01-01", "00:00")), str)
 
+    def test_cmdWrite(self):
+        self.login()
+        self.assertEqual(type(self.sip.cmdWrite("WN", "DUMMY", "H10", "+00:20", "2020-01-01", "00:00", "35/10;33/10")), str)
+
     def test_value(self):
         self.login()
         self.assertEqual(type(self.sip.value("WN", "DUMMY", "H10")), str)