{
 "manufacturer": "Siemens",
 "manufacturer_slug": "siemens",
 "model": "Two-Pipe Fan Coil BACnet ASC Controller - Application 2542 (Cooling or Heating)",
 "model_slug": "asc-2542-two-pipe-fan-coil",
 "short_model": "BACnet ASC Two-Pipe Fan Coil 2542",
 "aliases": [
  "Application 2542",
  "App 2542",
  "550-433",
  "Siemens BACnet ASC",
  "Siemens two-pipe fan coil controller",
  "BTEC"
 ],
 "equipment_type": "Fan coil unit controller",
 "applies_to": "Two-pipe fan coil units with one valve for heating or cooling and an optional second heating valve, on the Siemens Two-Pipe Fan Coil BACnet ASC controller 550-433.",
 "summary": "Application 2542 runs a two-pipe fan coil unit on the older Siemens BACnet ASC (terminal equipment) controller over BACnet MS/TP. Valve 1 modulates for cooling or heating depending on the water in the pipe, an optional second valve adds heat in sequence, and the fan runs all day or cycles with valve demand (CYCLE FAN). Heat/cool mode follows the pipe temperature sensor (SUPPLY TEMP against COOL TEMP and HEAT TEMP) or a field panel command.",
 "bacnet_transport": [
  "BACnet MS/TP"
 ],
 "firmware": null,
 "default_device_instance": null,
 "access_inferred": true,
 "notes": [
  "AI and BI objects are read-only. AO and BO objects are BACnet output objects with a priority array; the guide has no access column, so access is inferred from object type. Many AOs are calculated status values, not commands.",
  "Instances shown in braces in the guide may be unbundled at a field panel; that marking is not reproduced here.",
  "Units are given in US units (°F); the guide also lists SI factory defaults.",
  "The APPLICATION point range lists 2528, 2529 and 2542 through 2546 as applications of the same controller; only 2542 is covered here.",
  "Object names are kept as printed, including CLTR ADDRESS, VLVL 2 END, CLT TEMP and CTRL STPT.",
  "If the room or pipe temperature sensor fails, the controller keeps using the last good value."
 ],
 "source": {
  "title": "Two-Pipe Fan Coil BACnet ASC Controller, Application 2542 - Cooling or Heating, Application Notes",
  "doc_number": "140-0749",
  "revision_date": "2015-11",
  "url": "https://sid.siemens.com/api/khub/documents/irhhDwnQMAlC4IiuqChI~g/content"
 },
 "integration": {
  "summary": "Set the MS/TP address, then release the unit to application control. The BMS commands occupancy with DAY.NGT (BO 29) and the day setpoints and, without a pipe sensor, sets heat/cool through SUPPLY TEMP; it reads room temperature, fan status, valve position and the error status.",
  "minimum_points": [
   {
    "ref": "BO 29",
    "name": "DAY.NGT",
    "why": "DAY = occupied, NIGHT = unoccupied"
   },
   {
    "ref": "AO 6",
    "name": "DAY CLG STPT",
    "why": "Occupied cooling setpoint, °F"
   },
   {
    "ref": "AO 7",
    "name": "DAY HTG STPT",
    "why": "Occupied heating setpoint, °F"
   },
   {
    "ref": "BO 5",
    "name": "HEAT.COOL",
    "why": "Current mode: HEAT or COOL"
   },
   {
    "ref": "BO 46",
    "name": "FAN",
    "why": "Fan on/off"
   },
   {
    "ref": "AI 4",
    "name": "ROOM TEMP",
    "why": "Space temperature"
   },
   {
    "ref": "AO 49",
    "name": "VLV 1 POS",
    "why": "Valve 1 position, %"
   },
   {
    "ref": "AO 99",
    "name": "ERROR STATUS",
    "why": "Controller error code"
   }
  ],
  "enable": "Occupancy is DAY.NGT (BO 29). With a wall switch on DI 2 and WALL SWITCH (BO 18) = YES, the switch sets it; standalone with no switch the controller stays in day mode; on a network the field panel or BMS commands DAY.NGT. NGT OVRD (BO 21) shows a temporary night override from the room unit button.",
  "heartbeat": null,
  "remote_sensors": "Without a pipe sensor, the field panel commands SUPPLY TEMP (AI 15) below COOL TEMP for cooling or above HEAT TEMP for heating.",
  "setup": [
   "BACnet MS/TP only. CTLR ADDRESS (AO 1) holds the MS/TP address; the point table lists its factory value as 99.",
   "APPLICATION (AO 2) holds the application number; the point table lists its factory default as 2585."
  ],
  "gotchas": [
   "As shipped, the controller keeps all equipment OFF until it is released to application control (see the Siemens unit conditioner / fan coil start-up procedures).",
   "Loop gains, motor timing, rotation angles and setup codes are commissioning values; don't write them from the BMS routinely."
  ]
 },
 "points": [
  {
   "type": "AO",
   "instance": 1,
   "name": "CLTR ADDRESS",
   "description": "Controller MS/TP address",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 2,
   "name": "APPLICATION",
   "description": "Application number running in the controller",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 3,
   "name": "RMTMP OFFSET",
   "description": "Room temperature calibration offset",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 4,
   "name": "ROOM TEMP",
   "description": "Room temperature from the room unit",
   "units": "°F",
   "access": "R",
   "states": ""
  },
  {
   "type": "BO",
   "instance": 5,
   "name": "HEAT.COOL",
   "description": "Current heating/cooling mode",
   "units": "",
   "access": "C",
   "states": "0=COOL, 1=HEAT"
  },
  {
   "type": "AO",
   "instance": 6,
   "name": "DAY CLG STPT",
   "description": "Day (occupied) cooling setpoint",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 7,
   "name": "DAY HTG STPT",
   "description": "Day (occupied) heating setpoint",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 8,
   "name": "NGT CLG STPT",
   "description": "Night (unoccupied) cooling setpoint",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 9,
   "name": "NGT HTG STPT",
   "description": "Night (unoccupied) heating setpoint",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 11,
   "name": "RM STPT MIN",
   "description": "Lowest setpoint allowed from the room unit",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 12,
   "name": "RM STPT MAX",
   "description": "Highest setpoint allowed from the room unit",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 13,
   "name": "RM STPT DIAL",
   "description": "Setpoint from the room unit dial or keypad",
   "units": "°F",
   "access": "R",
   "states": ""
  },
  {
   "type": "BO",
   "instance": 14,
   "name": "STPT DIAL",
   "description": "Use the room unit setpoint dial",
   "units": "",
   "access": "C",
   "states": "0=NO, 1=YES"
  },
  {
   "type": "AI",
   "instance": 15,
   "name": "SUPPLY TEMP",
   "description": "Supply pipe water temperature",
   "units": "°F",
   "access": "R",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 16,
   "name": "VLV 1 START",
   "description": "Heating loop % where valve 1 starts to open",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 17,
   "name": "VLV 1 END",
   "description": "Heating loop % where valve 1 is full open",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "BO",
   "instance": 18,
   "name": "WALL SWITCH",
   "description": "Wall switch connected to DI 2",
   "units": "",
   "access": "C",
   "states": "0=NO, 1=YES"
  },
  {
   "type": "BI",
   "instance": 19,
   "name": "DI OVRD SW",
   "description": "Room unit night override button",
   "units": "",
   "access": "R",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "AO",
   "instance": 20,
   "name": "OVRD TIME",
   "description": "Night override duration",
   "units": "h",
   "access": "C",
   "states": ""
  },
  {
   "type": "BO",
   "instance": 21,
   "name": "NGT OVRD",
   "description": "Night override status",
   "units": "",
   "access": "C",
   "states": "0=DAY, 1=NIGHT"
  },
  {
   "type": "AO",
   "instance": 22,
   "name": "VLV 2 START",
   "description": "Heating loop % where valve 2 starts to open",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 23,
   "name": "VLVL 2 END",
   "description": "Heating loop % where valve 2 is full open",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "BI",
   "instance": 24,
   "name": "DI 2",
   "description": "Digital input 2",
   "units": "",
   "access": "R",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "BO",
   "instance": 29,
   "name": "DAY.NGT",
   "description": "Day/night (occupancy) mode",
   "units": "",
   "access": "C",
   "states": "0=DAY, 1=NIGHT"
  },
  {
   "type": "BO",
   "instance": 41,
   "name": "DO 1",
   "description": "Digital output 1",
   "units": "",
   "access": "C",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "BO",
   "instance": 42,
   "name": "DO 2",
   "description": "Digital output 2",
   "units": "",
   "access": "C",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "BO",
   "instance": 43,
   "name": "DO 3",
   "description": "Digital output 3",
   "units": "",
   "access": "C",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "BO",
   "instance": 44,
   "name": "DO 4",
   "description": "Digital output 4",
   "units": "",
   "access": "C",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "BO",
   "instance": 45,
   "name": "DO 5",
   "description": "Digital output 5",
   "units": "",
   "access": "C",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "BO",
   "instance": 46,
   "name": "FAN",
   "description": "Fan command",
   "units": "",
   "access": "C",
   "states": "0=OFF, 1=ON"
  },
  {
   "type": "AO",
   "instance": 48,
   "name": "VLV 1 COMD",
   "description": "Valve 1 command (heating or cooling)",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 49,
   "name": "VLV 1 POS",
   "description": "Valve 1 position (calculated)",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 51,
   "name": "MTR 1 TIMING",
   "description": "Motor 1 full-stroke time",
   "units": "s",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 52,
   "name": "VLV 2 COMD",
   "description": "Valve 2 command (second heating valve)",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 53,
   "name": "VLV 2 POS",
   "description": "Valve 2 position (calculated)",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 55,
   "name": "MTR 2 TIMING",
   "description": "Motor 2 full-stroke time",
   "units": "s",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 56,
   "name": "MTR 1 ROT ANG",
   "description": "Motor 1 rotation angle",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 57,
   "name": "MTR 2 ROT ANG",
   "description": "Motor 2 rotation angle",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 58,
   "name": "MTR SETUP",
   "description": "Motor enable/reverse setup (additive code)",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 59,
   "name": "DO DIR. REV",
   "description": "Digital output direction reverse (additive code)",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "BO",
   "instance": 60,
   "name": "CYCLE FAN",
   "description": "Cycle the fan with demand in day mode",
   "units": "",
   "access": "C",
   "states": "0=NO, 1=YES"
  },
  {
   "type": "AO",
   "instance": 61,
   "name": "COOL TEMP",
   "description": "Pipe temperature below which the unit cools",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 62,
   "name": "HEAT TEMP",
   "description": "Pipe temperature above which the unit heats",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 63,
   "name": "CLG P GAIN",
   "description": "Cooling loop proportional gain",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 64,
   "name": "CLG I GAIN",
   "description": "Cooling loop integral gain",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 65,
   "name": "CLG D GAIN",
   "description": "Cooling loop derivative gain",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 66,
   "name": "CLG BIAS",
   "description": "Cooling loop bias",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 67,
   "name": "HTG P GAIN",
   "description": "Heating loop proportional gain",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 68,
   "name": "HTG I GAIN",
   "description": "Heating loop integral gain",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 69,
   "name": "HTG D GAIN",
   "description": "Heating loop derivative gain",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 70,
   "name": "HTG BIAS",
   "description": "Heating loop bias",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 78,
   "name": "CLT TEMP",
   "description": "Temperature the controller is controlling to",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 79,
   "name": "CLG LOOPOUT",
   "description": "Cooling loop output",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 80,
   "name": "HTG LOOPOUT",
   "description": "Heating loop output",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 84,
   "name": "STAGE FAN",
   "description": "Valve opening that turns the fan on when cycling",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 85,
   "name": "SWITCH LIMIT",
   "description": "Loop output below which mode may switch",
   "units": "%",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 88,
   "name": "VALVE CNT",
   "description": "Number of heating valves (1 or 2)",
   "units": "",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 92,
   "name": "CTRL STPT",
   "description": "Active control setpoint",
   "units": "°F",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 96,
   "name": "CAL TIMER",
   "description": "Hours between automatic calibrations",
   "units": "h",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 98,
   "name": "LOOP TIME",
   "description": "Control loop interval",
   "units": "s",
   "access": "C",
   "states": ""
  },
  {
   "type": "AO",
   "instance": 99,
   "name": "ERROR STATUS",
   "description": "Controller error status code",
   "units": "",
   "access": "C",
   "states": ""
  }
 ],
 "page": "https://easybacnet.com/bacnet-points-lists/siemens/asc-2542-two-pipe-fan-coil",
 "note": "Provided as-is. Point availability varies by firmware and options; verify against the live device.",
 "disclaimer": "DISCLAIMER: reference only, provided AS IS with no warranty. May contain errors or be out of date. You must verify every point against the manufacturer's current documentation and the live device before use. easybacnet.com accepts no liability for its use and is not affiliated with the manufacturer. Terms: https://easybacnet.com/terms#content"
}