Index: leahi_dialin/dd/modules/levels.py
===================================================================
diff -u -recd89ae316cd2afa695dd4e93ac18b6004975efb -r9466b5c6b5867f392104a42608aa9542a7ff0358
--- leahi_dialin/dd/modules/levels.py	(.../levels.py)	(revision ecd89ae316cd2afa695dd4e93ac18b6004975efb)
+++ leahi_dialin/dd/modules/levels.py	(.../levels.py)	(revision 9466b5c6b5867f392104a42608aa9542a7ff0358)
@@ -5,7 +5,7 @@
 # THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 # WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 #
-# @file    heaters.py
+# @file    levels.py
 #
 # @author  (last)      Michael Garthwaite
 # @date    (last)      28-Oct-2024
@@ -25,6 +25,13 @@
 from leahi_dialin.utils.checks import check_broadcast_interval_override_ms
 from leahi_dialin.utils.conversions import integer_to_bytearray, float_to_bytearray
 
+@unique
+class DDLevelSensorEnum(DialinEnum):
+    D6_LEVEL = 0            # floater switch low, medium and high status
+    D63_LEVEL = 1           # bicarb level low or high status
+    D46_LEVEL = 2           # Spent dialysate air separation chamber level low or high status
+    NUM_OF_LEVELS = 3
+
 class DDLevels(AbstractSubSystem):
     """
 
@@ -42,42 +49,43 @@
         self.can_interface = can_interface
         self.logger = logger
 
-        self.floater1 = 0
-        self.bicarb_level = 0
-        self.spent_dialysate_level = 0
-        self.dd_levels_timestamp = 0
-
         if self.can_interface is not None:
             channel_id = DenaliChannels.dd_sync_broadcast_ch_id
             msg_id = MsgIds.MSG_ID_DD_LEVEL_DATA.value
-            self.can_interface.register_receiving_publication_function(channel_id, msg_id, self._handler_heaters_sync)
+            self.can_interface.register_receiving_publication_function(channel_id, msg_id, self._handler_levels_sync)
 
+        self.d6_level = 0
+        self.d63_level = 0
+        self.d46_level = 0
+        self.dd_levels_timestamp = 0
+
+
     @publish(["dd_levels_timestamp",
-                "floater1",
-              "bicarb_level",
-              "spent_dialysate_level"])
-    def _handler_heaters_sync(self, message, timestamp=0.0):
+                "d6_level",
+                "d63_level",
+                "d46_level"])
+    def _handler_levels_sync(self, message, timestamp=0.0):
         """
-        Handles published heaters message
+        Handles published levels message
 
-        @param message:  published heaters data message
+        @param message:  published levels data message
         @returns none
         """
-        self.floater1 = struct.unpack('i', bytearray(
+        self.d6_level = struct.unpack('i', bytearray(
             message['message'][MsgFieldPositions.START_POS_FIELD_1:MsgFieldPositions.END_POS_FIELD_1]))[0]
-        self.bicarb_level = struct.unpack('i', bytearray(
+        self.d63_level = struct.unpack('i', bytearray(
             message['message'][MsgFieldPositions.START_POS_FIELD_2:MsgFieldPositions.END_POS_FIELD_2]))[0]
-        self.spent_dialysate_level = struct.unpack('i', bytearray(
+        self.d46_level = struct.unpack('i', bytearray(
             message['message'][MsgFieldPositions.START_POS_FIELD_3:MsgFieldPositions.END_POS_FIELD_3]))[0]
 
         self.dd_levels_timestamp = timestamp
 
     def cmd_levels_broadcast_interval_override(self, ms: int, reset: int = NO_RESET) -> int:
         """
-        Constructs and sends broadcast time interval.
+        Constructs and sends dd levels broadcast time interval override.
         Constraints:
-            Must be logged into DG.
-            Given interval must be non-zero and a multiple of the DG general task interval (50 ms).
+            Must be logged into DD.
+            Given interval must be non-zero and a multiple of the DD general task interval (50 ms).
 
         @param ms: (int) Publish time interval in ms
         @param reset: (int) 1 to reset a previous override, 0 to override
@@ -94,7 +102,7 @@
                                               message_id=MsgIds.MSG_ID_DD_LEVELS_PUBLISH_INTERVAL_OVERRIDE_REQUEST.value,
                                               payload=payload)
 
-        self.logger.debug("Sending {} ms publish interval to the Heaters module".format(ms))
+        self.logger.debug("Sending {} ms publish interval to the Levels module".format(ms))
         # Send message
         received_message = self.can_interface.send(message)
 
@@ -108,11 +116,10 @@
 
     def cmd_level_status_override(self, level_sensor: int, status: int, reset: int = NO_RESET) -> int:
         """
-        Constructs and sends heater duty cycle override command
-            Must be logged into DG
-            There must be a minimum flow available for the heaters (FMP for primary and FMD for trimmer)
+        Constructs and sends level status cycle override command
+            Must be logged into DD.
 
-        @param level_sensor the level sensor to override its value (primary, trimmer) (0-1.0 order)
+        @param level_sensor the level sensor to override
         @param status the status value to override
         @param reset: (int) 1 to reset a previous override, 0 to override
         @returns 1 if successful, zero otherwise