GRMS Specification: Requirements Checklist for Hotel Room Control

A GRMS (guest room management system) specification is the client's document: what the room does, which hotel systems the GRMS exchanges data with and what is handed over at the end. The design is the contractor's answer: panel layouts, the bill of materials, the KNX topology and the ETS project. A good specification names functions, not part numbers, so that every requirement can be tested on a mock-up room.

Without such a document, bids cannot be compared: one supplier has included the curtains and the PMS link, another has not. How the room itself is configured in ETS is covered in the guide How to build a KNX hotel room; how a GRMS differs from a PMS is explained on the smart hotel page.

The first section holds the input data: they decide which controller goes into the room panel and how many devices each floor needs.

• Room types and counts. Standard, suite, apartment, connecting rooms — each with its own list of functions.
• HVAC type. 2-pipe or 4-pipe fan coil, split or VRF, radiators: this decides the room controller (see the table below).
• Room panel. ALLinBOX Hospitality v2 and MAXinBOX Hospitality v3 each take 4.5 DIN units^[1][6].
• Power at the door. IWAC Display v3 needs an external 24 V DC supply, with a maximum consumption of 50 mA^[2].
• Network and line power. ALLinBOX Hospitality v2 has a KNX power supply and a KNX-IP interface with an RJ45 socket (Ethernet 10/100)^[1], so the room panel needs a network port. The MAXinBOX Hospitality v3 datasheet lists neither a power supply nor an IP interface^[6]: for such rooms the KNX line power supply^[7] and the link to the hotel's IP network (IP Router or KNX-IP interface) are separate lines of the specification.
• Project stage. New build or refurbishment: Zennio names cabling as a limitation of KNX^[8], so the specification says where the bus cable can be run.

The compatibility of a specific air conditioner series is checked in Zennio's online tool^[13]. The room controllers are in the Climate category of our catalogue; the lock interfaces, the PMS, BMS and Reflecta licences and the servers are in Hotel installations.

Write functions as testable statements: "the HVAC switches off when the window is open", not "intelligent climate control".

Lighting and sockets

• A lighting scene for each room status. In Zennio's hotel catalogue: a welcome scene in a sold and occupied room, lights off in a sold and vacant room, and a staff scene in a room that is not sold^[3].
• Sockets that are switched off when the guest leaves: selected sockets in a vacant room, all of them in a room that is not sold^[3].
• A master switch for bedtime^[3]: ALLinBOX Hospitality v2 has two Master Light functions, MAXinBOX Hospitality v3 has one^[1][6].
• Luminaire types and dimming: they decide the controller outputs and any additional actuators.

Climate

• Setpoints for "sold, guest inside", "sold, guest out", "not sold" and "blocked for maintenance": these are the statuses by which Zennio's solution changes the setpoint^[3].
• Limits on the guest setpoint: the hotel sets them, the guest does not notice them, and the guest's chosen temperature is remembered until they return^[3]. The hospitality thermostat also offers a hidden setpoint offset^[10].
• Open window or door: Zennio switches the HVAC off and locks the thermostat^[3]; the hospitality thermostat stays in Protection mode until every window and door is closed^[10].
• Pre-arrival: condition and dehumidify the room before the guest arrives^[3].

Curtains

If the curtains are motorised, state the motor type and the number of channels. On MAXinBOX Hospitality v3 two 16 A outputs can be configured as a shutter channel^[6]; ALLinBOX Hospitality v2 has no shutter channels^[14]. Zennio does not make curtain motors or tracks, so the specification names the supplier of the drive.

Do Not Disturb, Make Up Room and the doorbell

State where the guest sets the status and where the staff see it. In the typical room of Zennio's hotel catalogue the guest chooses DND or MUR on Tecla RGB 70 keypads at the entrance, and the RingBOX doorbell has a Do Not Disturb mode and needs no extra power supply^[3]; it has 4 doorbells, 8 tones and 65 dB at one metre^[15]. Outside the door the status is shown by IWAC Display v3^[16]; note whether reception needs to see it too.

Occupancy

Write the requirement as a result: a sleeping guest must not "disappear". If one guest leaves while another sleeps, the room may drop to unoccupied; the False Non-Occupied Detection function of the Motion Detector module corrects such a false "vacant" by restoring the saved scene at the next movement (or after the set number of detections, if the detection filter is enabled), and its use can be limited to sold rooms^[17]. The specification decides whether that short transition is acceptable; the setting itself is described in the guide How to build a KNX hotel room.

According to Zennio's hotel catalogue, the system integrates with SALTO, Vingcard, Onity and dormakaba locks and tells whether a guest or an employee is entering^[3]. If the locks are already installed or chosen, the specification needs a section of questions for their supplier.

• Lock make, model and lock server. For Vingcard, KILock sends its data over TCP/IP to the KILock Server (KLS), which is connected to the Visionline server^[18].
• Radio link. KILock talks to the lock over Zigbee and Bluetooth at 2.4 GHz^[19], so its location is agreed with the lock supplier.
• Lock events. For Vingcard, KILock has objects for the door state, guest or employee, sold or not sold, DND, the room state and the "low battery" and "door left open" alarms^[18].
• Onity. KILock switches DND on and off at the lock and changes the room status on its indicators, but does not control the deadbolt^[18].
• SALTO. For SALTO InRoomNode there is KIRN, 39 × 39 × 10.5 mm, for a wall back box or a distribution box^[20].
• dormakaba. Integration is stated in Zennio's hotel catalogue^[3]; the device and protocol are confirmed for the project.

If there are no locks yet, Zennio's own access control can be specified. IWAC Display v3 opens the room with MIFARE DESFire 2K and MIFARE Classic 1K cards and over Bluetooth, and sends the command to the Securel v3 secure relay over an encrypted serial link^[2]; its OLED display shows the room number^[16]. The relay drives one electric strike^[21]. A card can be tied to a group — staff, cleaning, security — only on MIFARE DESFire^[4].

For IWAC Display v3, Zennio states that a Zennio server is required^[22]: cards are written and Bluetooth keys issued by the Z-Access software^[9], and the key on the phone comes from the ZenKey app^[16]. In our catalogue the IP network and server items are not part of IWAC, so they are a separate line of the specification. Zennio states that access works offline^[9]; entries granted without a connection to the KNX bus are reported by the access module with the Offline Access object once power is back^[4]. The specification lists the card type, access groups, phone keys and the electric strike from the door supplier. The devices are in the Access control category of our catalogue.

Zennio's GRMS reaches the hotel's central services, including the BMS, over the existing IP network, without new wiring^[3]. From the PMS it receives check-in and check-out data^[3]: in the room this becomes a sold or not sold object that changes the thermostat mode and the occupancy logic^[23][17]. For the BMS, Zennio declares Modbus and BACnet integration, and an API for the other hotel systems^[3].

Zennio's central software for hotels is Reflecta^[3]. For the PMS, our catalogue has a PMS Integration configuration item and per-room licences Type A and Type B; we confirm which one applies for the hotel's PMS, as we do for the BMS licences. The room points for the BMS and their formats are in the guide What KNX sends to a BMS.

In a hotel the KNX bus runs through every room and the IP network is shared, so protection is written down explicitly. KNX Data Secure is supported by MAXinBOX Hospitality v3^[6], Securel v3^[21], RingBOX^[15], KILock^[19] and KIRN^[20], and ALLinBOX Hospitality v2 supports both Data Secure and KNX IP Secure^[1]. Only what belongs in the specification is listed below.

• ETS version. Devices with KNX Secure are commissioned from ETS 5.7 or later, and a project with a secure device must be password-protected^[5].
• Keys. At the first secure commissioning ETS replaces the device's factory key (FDSK) with an individual Tool Key; the keys are stored in the project^[5].
• Which addresses to secure. Security is chosen per group address^[5], so state which addresses a third-party system (the BMS, a PMS gateway) must be able to read.
• Tunnels. Each secure tunnelling address has its own password^[5]: state who keeps them and to whom they are handed.

On top of the usual KNX handover package — the ETS project, passwords, addresses and wiring diagrams — a hotel needs:

• Mock-up room. One room of each type before roll-out; the hotel tests it against the requirements table and signs a report.
• Roll-out. The parameters and group addresses of the accepted room are copied to the other rooms of the same project with the Zennio Parameter Copier app for ETS, then checked manually, as its manual requires^[25].
• Point lists. "Group address → point" tables for the PMS, BMS and central software: without them any change to the project breaks the integration.
• Room documents. A status table (what lights, sockets and climate do in each status), panel diagrams by room type and the as-built bill of materials.
• Service access. Who connects to the system over IP; for a shared network there are devices with KNX IP Secure, such as IP Router^[24].

The table can go into a tender as it is: the requirement, the question to settle with the client before requesting bids, and Zennio's answer with a reference to the manufacturer's document.

• A key card holder. Zennio does not make one: occupancy comes from the sensors and the door^[3].
• Leak, smoke and gas detectors. Zennio's solution sends leak and smoke notifications^[26], but Zennio makes no detectors of its own: third-party detectors with a dry contact are wired to the inputs of Zennio devices.
• Curtain motors and tracks. They come from the curtain manufacturer; Zennio controls the drive.
• A KLIC gateway for any make. KLIC gateways exist for specific makes and series, and there is none for Hisense VRF^[9]; check the series before the tender^[13].
• Energy savings as a guarantee. "Up to 60% compared with a conventional system" is Zennio's own statement^[3]; for a specific property the saving is estimated in the design.
• PMS and lock compatibility before it is confirmed. The manufacturer confirms compatibility with the hotel's systems for the project.

We are the official Zennio distributor in Kazakhstan. If you are preparing a hotel tender here, we can check the specification against Zennio equipment and draft the bill of materials per room type — send it to us.