Hotel-Room Object

Comprehensive, step-by-step manual for the Hotel-Room Object that you can use directly on the Hotel projects

Hospitality installations — guest rooms, PMS integration, and iNELS Harmony.

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1. What it is

The Hotel-Room Object is a virtual device inside the CU3 central unit, designed specifically for hotel and hospitality projects. It aggregates all guest, room and climate functions into a single object, so the information is available to reception software, a PMS (Property Management System) or a BMS without handling dozens of separate signals.

Everything about a guest room — occupied or empty, do-not-disturb, temperature, window open — is unified in one place.

Why it matters

• Instead of configuring dozens of signals separately, all values are consolidated in one object

• PMS/BMS integration needs only one MQTT topic per room, which minimises complexity and errors

• Housekeeping sees MUR and DND instantly in the PMS — no wasted trips to rooms

• Maintenance can monitor HVAC performance (temperature, humidity, valve status) remotely

• Reception gets real-time visibility of guest presence, alarms and scenes

• Fewer manual processes → lower staffing costs and higher efficiency

• Works equally for small boutique hotels and large multi-building resorts

• Each CU3 handles more than one Hotel-Room object, all with the same interface

• Use the iNELS Hotel Reservation Software (iHRS) or connect a third-party PMS/BMS

• The open MQTT/JSON interface suits cloud platforms, custom dashboards and mobile apps

Rooms will not appear in iNELS Harmony without this object

This is the one that catches people out. You can wire a guest room perfectly — lights, heating, card reader, everything working — and the room still will not be discovered by iNELS Harmony.

Harmony finds rooms by looking for Hotel-Room objects. No object, no room. The installation works locally and looks finished, but the hotel's management layer sees nothing.

On any project that will use Harmony, add the Hotel-Room object from the start. Retrofitting it across eighty rooms after commissioning is a long, avoidable job.

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2. Main features

Group	What it covers
Guest & room status	Occupancy, Do Not Disturb (DND), Make Up Room (MUR), Butler/service call
Climate control	Actual temperature, humidity, dew point, setpoints, correction
HVAC control	Mode, plan, fan speed
Room events	Door/window status, card events
Scenes	Welcome scene + 5 customisable room scenes
MQTT integration	One topic per room, JSON payload
Bidirectional	Both read status and write control are supported

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3. Adding it to a project

You need a current iDM version for the Hotel object to be available, and current CU3 firmware (Chapter 25).

The structure is two levels:

  CU3
  └── Hotel-Room-Modul              ← the module: add once
      ├── Hotel-Room   Room-Id 101  ← one per guest room
      ├── Hotel-Room   Room-Id 102
      └── Hotel-Room   Room-Id 103

One Hotel-Room unit per physical guest room. A forty-room floor is forty units under one module.

Step 1 — Add the module

1. Project ribbon tab → Device manager.

2. Select the central unit → New slave.

3. Choose Hotel-Room-Modul → OK.

The module has no parameters. It is a container.

Step 2 — Add a room

1. Select the Hotel-Room-Modul.

2. New unit → Hotel-Room → OK.

3. Set its Description to something a human recognises — Room 101.

Step 3 — Set the parameters

Select the Hotel-Room unit. In Parameters you will see:

Parameter	Range	What it is
Address	assigned by iDM3	Unique identifier of the object in the CU3
Name / Description	text	For project documentation
Room-Id	0 – 65535 (default 1)	Links the object to the hotel room number

Enter the hotel's actual room number as Room-Id. Room 101 gets 101; room 1204 gets 1204.

Room-Id is not the Address. They are different fields with different jobs, and the PMS integrator needs both:

	Set by	Used by
Address	iDM3	the central unit, and the MQTT topic
Room-Id	you	the PMS, Harmony, and the hotel

Get Room-Id right the first time. It is how the PMS and Harmony identify the room. Changing it later means the management system loses track of that room until its own configuration is updated to match.

Rooms with no number. Give staff rooms, plant rooms and suites a consistent scheme — 9001 upwards, say — rather than leaving them at the default 1. Two objects sharing Room-Id 1 is a problem you will find late.

Repeat steps 2 and 3 for every room.

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4. Device structure — the 23 datapoints

Expand a Hotel-Room unit and you will find 23 devices. They are ordinary iNELS objects: wire them, use them in conditions, read them in Monitor. The names in brackets are what you will see in the device tree.

Guest & room status

Datapoint	Carries
Occupancy	Guest in room (true/false)
DND	Do Not Disturb
MUR	Make Up Room
Buttler	Service call

"Buttler" is spelled that way in the software — with two t's. You are looking at the right datapoint.

Climate control

Datapoint	Carries
Actual-Therm-AOUT	Actual temperature
Required-Heat-Therm-AOUT	Required heat setpoint
Required-Cool-Therm-AOUT	Required cool setpoint
Set-Therm-AIN	The temperature the guest or PMS is asking for
Correction	Calibration offset
Humidity-AOUT	Relative humidity
Dew-Point-AOUT	Dew point

Read the suffixes. -AOUT datapoints are values the object publishes — what the room is doing. -AIN datapoints are written into the object — what someone is asking for.

Dew point matters more than it sounds. In humid climates, cooling below the dew point causes condensation on chilled surfaces. Hotels commonly use this datapoint to limit how far cooling can go.

HVAC control

Datapoint	Carries
Control-IN	Heat / Cool / Off
Control-Mode-IN	Plan / Manual / Eco / Dry etc.
Control-Plan-IN	Base / Holiday / Public Holiday
Control-Fan-Speed-IN	Low / Medium / High / Auto / Off

The numeric values behind each of these are in the Payload reference at the end of this page.

Room events

Datapoint	Carries
Door-Status	Open / Closed
Window-Status	Open / Closed

Scenes

Datapoint	Carries
Welcome-Scene	Triggered when a guest first enters
Scene1 – Scene5	Five further scenes, customisable

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5. Linking to a Heat/Cool controller

The Hotel-Room object holds the guest's request. A Heat/Cool area (HCA) is what regulates the room (Chapter 10). They have to be joined.

1. Add a Controller for Heating and Cooling (HCA) in System manager → Heat/Cool areas tab.

2. Under Connections, select the Hotel-Room object for this room.

iDM will automatically create internal wires between the Hotel-Room object and the HCA. The climate data — actual temperature, required heat setpoint, required cool setpoint, correction, humidity, dew point — is wired for you.

Important: You must still wire the HCA outputs (Fan regulator, Valve regulator) to the physical output relays or analog outputs controlling the HVAC equipment.

The automatic linking connects the object to the controller, not the controller to the hardware. A room where the guest can set a temperature, the PMS shows it correctly, and nothing physically happens is almost always this step, left undone.

Repeat per room — eighty rooms means eighty Heat/Cool areas.

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6. Wiring it to the room hardware

The automatic link covers climate. Everything else you wire yourself, using the ordinary actor → function → consumer model (Chapter 2).

Occupancy from a card holder

Actor	Action	Function	Consumer
Card holder input	Digital IN switch ON	DIGITAL_ON	Occupancy
Card holder input	Digital IN switch OFF	DIGITAL_OFF	Occupancy

Then use Occupancy as an actor for everything that should follow the guest:

Actor	Action	Function	Consumer
Occupancy	Digital IN switch ON	DIGITAL_ON	Welcome-Scene
Occupancy	Digital IN switch OFF	DIGITAL_GROUP_OFF	room lights group
Occupancy	Digital IN switch OFF	HEATING_COOLING_SWITCH_TO_FAVORITE1	the room's HCA

That last wire is where a hotel saves most of its energy: an empty room falls back to setback temperature automatically.

DND, MUR and butler from the guest panel

Use a GSB3 glass switch — a GSB3-60 or GSB3-90, for example — as the bedside or entrance panel, with one button per guest function.

Actor	Action	Function	Consumer
GSB3 button 1	Short down	DIGITAL_SWITCH	DND
GSB3 button 2	Short down	DIGITAL_SWITCH	MUR
GSB3 button 3	Short down	DIGITAL_ON	Buttler
DND	Digital IN switch ON	DIGITAL_ON	GSB3 button 1 backlight

Drive the backlights from the datapoint, not the button. Guests need to see whether DND is on. Taking the indication from the DND datapoint means the lamp always shows the real state — including when housekeeping or the PMS clears it remotely, which a button-driven indicator would miss entirely.

The older EST3 and EHT3 hotel panels are obsolete. They still appear in the unit list so you can service existing installations, but do not specify them for new work. Use a GSB3 or current equivalent.

Door and window

Actor	Action	Function	Consumer
Door contact	Digital IN switch ON	DIGITAL_ON	Door-Status
Window contact	Digital IN switch ON	DIGITAL_ON	Window-Status

Window-Status is worth wiring even where the hotel has not asked for it: the HCA can suspend heating while a window is open, which pays for the contact quickly.

Scenes

Wire Welcome-Scene and Scene1–Scene5 to lighting groups, blinds or the television. Because they are datapoints on the object, the PMS can trigger them too — so a scene can be fired by the front desk as easily as by the guest.

Useful patterns

Goal	How
Setback when the guest leaves	Occupancy off → HEATING_COOLING_SWITCH_TO_FAVORITE1
No housekeeping while DND is on	Condition: Restriction value — DND = OFF
Stop cooling below dew point	Condition comparing Dew-Point-AOUT against the cooling setpoint
Heating off with a window open	Window-Status as a condition, or the HCA's window handling
Lights off when the room empties	Occupancy off → DIGITAL_GROUP_OFF on the room lighting group
Welcome on first entry	Occupancy on → DIGITAL_ON on Welcome-Scene

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7. MQTT integration

Topic Structure

• Status (publish)

  inels/status/<CU3_MAC>/Hotelroom/<HotelRoom_Address>

• Set (subscribe)

  inels/set/<CU3_MAC>/Hotelroom/<HotelRoom_Address>

Example Status Payload

{
  "timestamp": "2025-08-25T18:45:52Z",
  "room_id": "1",
  "occupancy": false,
  "dnd": false,
  "mur": true,
  "buttler": true,
  "temperature": {
    "current": 23.5,
    "set_heat": 22,
    "set_cool": 24,
    "correction": 1
  },
  "humidity": 55,
  "dew_point": 14.8,
  "control": "Heat",
  "control_mode": "Plan",
  "control_plan": "Base",
  "fan_speed": "Low",
  "door_status": "Closed",
  "window_status": "Closed",
  "scenes": {
    "welcome_scene": true,
    "scene_1": false,
    "scene_2": true,
    "scene_3": false,
    "scene_4": true,
    "scene_5": false
  }
}

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Example Set Payload

{
  "dnd": true,
  "mur": false,
  "buttler": false,
  "temperature": {
    "set_heat": 21,
    "set_cool": 24,
    "correction": 0
  },
  "control": "Cool",
  "control_mode": "Manual",
  "control_plan": "Holiday",
  "fan_speed": "Auto",
  "door_status": "Closed",
  "window_status": "Closed",
  "scenes": {
    "welcome_scene": false,
    "scene_1": true,
    "scene_2": false,
    "scene_3": false,
    "scene_4": false,
    "scene_5": true
  }
}

Payload reference

Fan Speed

Key	Name	Description
0	Low	Fan at low speed
1	Med	Fan at medium speed
2	Hi	Fan at high speed
3	Auto	Automatic fan speed control
4	Off	Fan switched off

HVAC control

Key	Name	Description
0	Cool	Cooling mode active
1	Heat	Heating mode active
2	Off	System switched off

HVAC Modes

Key	Name	Description
0	Cool	Cooling mode active
1	Heat	Heating mode active
2	Off	System switched off

Control Modes

Key	Name	Description
0	Plan	Follow scheduled plan
1	Favorite1	User-defined favorite mode 1
2	Favorite2	User-defined favorite mode 2
3	Favorite3	User-defined favorite mode 3
4	Favorite4	User-defined favorite mode 4
5	Fan	Fan-only mode
6	Eco	Energy-saving mode
7	Manual	Manual override mode
8	Dry	Dehumidification mode

Plan Control Modes

Key	Name	Description
0	Base	Base (default) plan
64	Holiday	Holiday plan
128	Public Holiday	Public holiday plan (special case)

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8. If a room does not appear in iNELS Harmony

Check
Does the room have a Hotel-Room unit?	No object, no room — see §1
Is the Room-Id set and unique?	Two rooms sharing an Id will not both appear
Was the project uploaded?	Save to central unit
Is MQTT enabled and connected?	Chapter 22
Is the CU3 firmware current?	Chapter 25

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9. Before handover

• Every guest room has its own Hotel-Room unit

• Every Room-Id matches the hotel's real room number, and none are duplicated

• Each room has a Heat/Cool area linked under Connections

• Fan and valve regulator outputs are wired to physical hardware

• Occupancy, DND, MUR and door/window are wired and tested

• Guest panel is a current unit (GSB3 or similar), not an obsolete EST3/EHT3

• Guest panel backlights follow the datapoints, not the buttons

• MQTT is enabled and the rooms appear in Harmony

• The PMS integrator has a table of Address ↔ Room-Id

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See also: Chapter 10 — Heating and cooling · Chapter 20 — System manager · Chapter 24 — External systems