{
 "manufacturer": "Vaisala",
 "manufacturer_slug": "vaisala",
 "model": "HMD65 humidity and temperature duct transmitter (BACnet MS/TP)",
 "model_slug": "hmd65",
 "aliases": [
  "HMD65",
  "Vaisala HMD65",
  "HMD65 BACnet",
  "M212243EN"
 ],
 "equipment_type": "Humidity and temperature sensor (duct transmitter)",
 "applies_to": "Vaisala HMD65 duct-mounted relative humidity and temperature transmitters with the RS-485 port set to BACnet MS/TP.",
 "summary": "The HMD65 duct transmitter selects Modbus RTU or BACnet MS/TP by DIP switch. On BACnet it serves relative humidity, temperature and six calculated humidity values (dewpoint, dew/frost point, wet bulb, absolute humidity, mixing ratio, enthalpy) as Analog Inputs, plus a writable operating pressure value used in the calculations.",
 "bacnet_transport": [
  "BACnet MS/TP"
 ],
 "firmware": null,
 "default_device_instance": null,
 "access_inferred": false,
 "notes": [
  "Units of the temperature and calculated objects can be switched between metric and non-metric over BACnet; absolute humidity and mixing ratio use Vaisala-defined codes for the non-metric units.",
  "Analog Input Present_Value can be written only when Out_Of_Service is set.",
  "AI 1 and AI 2 report Reliability OVER_RANGE/UNDER_RANGE outside 0-100 %RH and -40 to +80 °C.",
  "Source: HMD65 User Guide M212243EN-C, BACnet Reference (Vaisala online documentation)."
 ],
 "source": {
  "title": "HMD65 User Guide, BACnet Reference",
  "doc_number": "M212243EN-C",
  "revision_date": null,
  "url": "https://docs.vaisala.com/r/M212243EN-C/en-US"
 },
 "integration": {
  "summary": "Set BACnet mode, MAC address and bit rate on the DIP switches, then read RH and temperature (and dewpoint or enthalpy if needed). If the site is far from sea level, write the operating pressure once.",
  "minimum_points": [
   {
    "ref": "AI 1",
    "name": "RH",
    "why": "Relative humidity, %"
   },
   {
    "ref": "AI 2",
    "name": "T",
    "why": "Temperature"
   },
   {
    "ref": "AI 3",
    "name": "Td",
    "why": "Dewpoint temperature"
   }
  ],
  "enable": null,
  "heartbeat": null,
  "remote_sensors": "AV 1 OPER P (operating pressure, hPa, default 1013.25) can be written by the BMS for the humidity calculations.",
  "setup": [
   "MAC 0-127 (master only) on the address DIP switches; a mode DIP switch selects BACnet MS/TP.",
   "Bit rate 9600-115200 by DIP switch; all-off = 38400 for BACnet; the 4800 setting also gives 38400.",
   "Fixed 8N1. 120 ohm termination by DIP switch.",
   "Device instance, name, location and Max_Master are set with Vaisala Insight (USB cable 219690); remote management password default 1234.",
   "No segmentation; Max_Info_Frames 1."
  ],
  "gotchas": [
   "4800 bps is not valid for BACnet; the transmitter falls back to 38400.",
   "OPER P is stored in non-volatile memory; write it once, not cyclically."
  ]
 },
 "points": [
  {
   "type": "AI",
   "instance": 1,
   "name": "RH",
   "description": "Relative humidity",
   "units": "%RH",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 2,
   "name": "T",
   "description": "Temperature",
   "units": "°C (Units writable: °C/°F)",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 3,
   "name": "Td",
   "description": "Dewpoint",
   "units": "°C or °F",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 4,
   "name": "Tdf",
   "description": "Dew/frost point",
   "units": "°C or °F",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 5,
   "name": "Tw",
   "description": "Wet bulb temperature",
   "units": "°C or °F",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 6,
   "name": "a",
   "description": "Absolute humidity",
   "units": "g/m3 or gr/ft3",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 7,
   "name": "x",
   "description": "Mixing ratio",
   "units": "g/kg or gr/lb",
   "access": "R",
   "states": ""
  },
  {
   "type": "AI",
   "instance": 8,
   "name": "h",
   "description": "Enthalpy",
   "units": "kJ/kg or Btu/lb",
   "access": "R",
   "states": ""
  },
  {
   "type": "AV",
   "instance": 1,
   "name": "OPER P",
   "description": "Operating pressure for humidity calculations (default 1013.25)",
   "units": "hPa",
   "access": "W",
   "states": ""
  }
 ],
 "page": "https://easybacnet.com/bacnet-points-lists/vaisala/hmd65",
 "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"
}