The MDT Glass Touch 4 inch panels come in two versions, Smart and Plus, each in white or black. Both have a 720 × 720 colour display, support KNX Data Secure and work as a room temperature controller. Both also need a separate 24 V DC supply on top of the KNX bus, and that is the detail to settle before the walls are closed.
What MDT has announced
On 16 October 2026 MDT announced that the Glass Touch Smart and Glass Touch Smart Plus in the 4 inch size are available. They had been listed as coming soon for Light + Building 2026, the Frankfurt fair held in March, and the October announcement is the point at which MDT calls them available.
The figures below come from MDT's announcement, its product page and the datasheet for the Smart variant. Where those sources differ, the table says so.
| Item | What MDT states |
|---|---|
| Display | 4 inch colour TFT, 720 × 720 pixels |
| Front plate | 92 × 92 mm, 12.5 mm thick; installation depth in the switch box 22 mm |
| Layouts | One to four buttons per page, up to 32 functions |
| Security | KNX Data Secure |
| Room control | Temperature and humidity sensor, room temperature controller |
| Auxiliary supply | 24 V DC; the Smart datasheet gives a working range of 21 to 30 V DC, the announcement says 24 to 30 V DC |
| Versions | Smart and Plus, each in white or black |
What a 4 inch screen changes on a wall
A conventional KNX wall switch gives each function a physical key. A panel like this gives you a small screen with up to four buttons on a page, so one plate can hold what used to need a row of keys: a lighting scene, the blinds, the temperature. That is useful where wall space is limited, or where the interior designer wants one clean surface instead of three.
The trade is that a passive switch becomes a device with a layout to design and a power supply to wire. Our view, and it is only a view: that is a fair trade in a living room or an entrance, while in a bedroom, where people want a switch they can find in the dark, some owners will still prefer keys.
The planning point: power and wiring
A KNX line carries its own supply, but MDT specifies a separate auxiliary supply for these panels. Design to 24 V DC, and check the datasheet of the exact variant before ordering the supply, since the two MDT documents quote slightly different ranges. MDT names its own 24 V unit, the STV-0024.01, as an example.
That has three consequences for a new build.
- A second pair of conductors to each panel. KNX cable of the J-Y(St)Y 2 × 2 × 0.8 type has a spare pair, conventionally yellow and white. Merten's technical information notes that this pair may carry safety extra-low voltage only, to a maximum of 2.5 A, and that it must not be confusable with the bus pair. Whether to use it or to pull a separate cable is a design decision, and it is cheaper to make it now than after plastering.
- Voltage at the far end. The Smart datasheet gives 21 V as the lower limit. Over a long run of thin conductors the drop is not zero, so measure or calculate the voltage at the farthest panel rather than assuming the supply's output arrives intact.
- Room in the distribution board. The supply is a DIN-rail device that someone has to place, protect and label. Count the panels per supply and leave headroom for the ones that get added during the project.
The wall box
The Smart datasheet lists a standard switch box in EU, UK, Swiss and Chinese formats. Indian modular boxes are not on that list. Before civil work starts, ask for the installation drawing and confirm that the box you intend to use fits, with enough depth behind it for the terminals and the bend of the cable. We would rather say that plainly than promise a fit that nobody has checked.
Smart or Plus
Plus is the fuller version. According to MDT's product page it adds an RGBW circumferential light, a loudspeaker for acoustic feedback, six time switches, a code lock for four users and two binary inputs for potential-free contacts. The Smart has a white orientation light and one code user. The speaker is for feedback tones, not for playing music.
Which one belongs in which room is a separate question, and we take it room by room in the next post.
Security, ETS and handover
KNX Data Secure authenticates and encrypts group telegrams on the bus. In practice it adds key and password management to commissioning, so agree at handover who holds the ETS project, its password and the keys. MDT's catalogue specifies ETS 5 or later for these panels.
A short list to settle before ordering
- Which rooms get a screen, and which keep keys.
- Smart or Plus for each of those rooms.
- Where the 24 V supplies sit, and how many panels each one feeds.
- The cable route for the second pair, or a separate cable.
- The wall-box type and its depth, confirmed against the drawing.
- Who holds the ETS project and the Secure keys after handover.
Availability in India
MDT calls the panels available from October. For stock, lead time and a quotation in India, please ask us: we do not publish prices on the blog, and a quote depends on the variant and the quantity. The wider MDT KNX range at Morion is on our brand page.
Questions people ask
Can the panel run from the KNX bus alone?
Not according to MDT. The specification calls for an auxiliary supply of 24 V DC in addition to the connection to the bus.
Do I need ETS to set it up?
Yes. Like any KNX device it is parameterised in ETS, and MDT's catalogue specifies ETS 5 or later. Budget commissioning time for each panel's pages, not only for the actuators.
Is there a larger version?
MDT also makes a 6 inch Glass Touch Smart panel, which is on our MDT page. This post covers only the 4 inch models.
Planning a project with these panels? Send us the room list and the wall-box type, and we will check the fit and the supply before the electrical drawing is final: talk to our team.
Sources checked on 31 October 2026
- MDT, Now available: the MDT Glass Touch Smart / Plus 4 inch, 16 October 2026.
- MDT, Glass Touch Smart Plus 4 inch product page.
- MDT, datasheet GTS-04TW.01S, Glass Touch Smart 4 inch, 04/26.
- MDT, datasheet GTS-P4TW.01S, Glass Touch Smart Plus 4 inch, 04/26.
- Merten, Technische Informationen KNX, 2016, on the spare pair and bus cable.
The MDT Glass Touch 4 inch panels come in two versions, Smart and Plus, each in white or black. Both have a 720 × 720 colour display, support KNX Data Secure and work as a room temperature controller. Both also need a separate 24 V DC supply on top of the KNX bus, and that is the detail to settle before the walls are closed.
What MDT has announced
On 16 October 2026 MDT announced that the Glass Touch Smart and Glass Touch Smart Plus in the 4 inch size are available. They had been listed as coming soon for Light + Building 2026, the Frankfurt fair held in March, and the October announcement is the point at which MDT calls them available.
The figures below come from MDT's announcement, its product page and the datasheet for the Smart variant. Where those sources differ, the table says so.
| Item | What MDT states |
|---|---|
| Display | 4 inch colour TFT, 720 × 720 pixels |
| Front plate | 92 × 92 mm, 12.5 mm thick; installation depth in the switch box 22 mm |
| Layouts | One to four buttons per page, up to 32 functions |
| Security | KNX Data Secure |
| Room control | Temperature and humidity sensor, room temperature controller |
| Auxiliary supply | 24 V DC; the Smart datasheet gives a working range of 21 to 30 V DC, the announcement says 24 to 30 V DC |
| Versions | Smart and Plus, each in white or black |
What a 4 inch screen changes on a wall
A conventional KNX wall switch gives each function a physical key. A panel like this gives you a small screen with up to four buttons on a page, so one plate can hold what used to need a row of keys: a lighting scene, the blinds, the temperature. That is useful where wall space is limited, or where the interior designer wants one clean surface instead of three.
The trade is that a passive switch becomes a device with a layout to design and a power supply to wire. Our view, and it is only a view: that is a fair trade in a living room or an entrance, while in a bedroom, where people want a switch they can find in the dark, some owners will still prefer keys.
The planning point: power and wiring
A KNX line carries its own supply, but MDT specifies a separate auxiliary supply for these panels. Design to 24 V DC, and check the datasheet of the exact variant before ordering the supply, since the two MDT documents quote slightly different ranges. MDT names its own 24 V unit, the STV-0024.01, as an example.
That has three consequences for a new build.
- A second pair of conductors to each panel. KNX cable of the J-Y(St)Y 2 × 2 × 0.8 type has a spare pair, conventionally yellow and white. Merten's technical information notes that this pair may carry safety extra-low voltage only, to a maximum of 2.5 A, and that it must not be confusable with the bus pair. Whether to use it or to pull a separate cable is a design decision, and it is cheaper to make it now than after plastering.
- Voltage at the far end. The Smart datasheet gives 21 V as the lower limit. Over a long run of thin conductors the drop is not zero, so measure or calculate the voltage at the farthest panel rather than assuming the supply's output arrives intact.
- Room in the distribution board. The supply is a DIN-rail device that someone has to place, protect and label. Count the panels per supply and leave headroom for the ones that get added during the project.
The wall box
The Smart datasheet lists a standard switch box in EU, UK, Swiss and Chinese formats. Indian modular boxes are not on that list. Before civil work starts, ask for the installation drawing and confirm that the box you intend to use fits, with enough depth behind it for the terminals and the bend of the cable. We would rather say that plainly than promise a fit that nobody has checked.
Smart or Plus
Plus is the fuller version. According to MDT's product page it adds an RGBW circumferential light, a loudspeaker for acoustic feedback, six time switches, a code lock for four users and two binary inputs for potential-free contacts. The Smart has a white orientation light and one code user. The speaker is for feedback tones, not for playing music.
Which one belongs in which room is a separate question, and we take it room by room in the next post.
Security, ETS and handover
KNX Data Secure authenticates and encrypts group telegrams on the bus. In practice it adds key and password management to commissioning, so agree at handover who holds the ETS project, its password and the keys. MDT's catalogue specifies ETS 5 or later for these panels.
A short list to settle before ordering
- Which rooms get a screen, and which keep keys.
- Smart or Plus for each of those rooms.
- Where the 24 V supplies sit, and how many panels each one feeds.
- The cable route for the second pair, or a separate cable.
- The wall-box type and its depth, confirmed against the drawing.
- Who holds the ETS project and the Secure keys after handover.
Availability in India
MDT calls the panels available from October. For stock, lead time and a quotation in India, please ask us: we do not publish prices on the blog, and a quote depends on the variant and the quantity. The wider MDT KNX range at Morion is on our brand page.
Questions people ask
Can the panel run from the KNX bus alone?
Not according to MDT. The specification calls for an auxiliary supply of 24 V DC in addition to the connection to the bus.
Do I need ETS to set it up?
Yes. Like any KNX device it is parameterised in ETS, and MDT's catalogue specifies ETS 5 or later. Budget commissioning time for each panel's pages, not only for the actuators.
Is there a larger version?
MDT also makes a 6 inch Glass Touch Smart panel, which is on our MDT page. This post covers only the 4 inch models.
Planning a project with these panels? Send us the room list and the wall-box type, and we will check the fit and the supply before the electrical drawing is final: talk to our team.
Sources checked on 31 October 2026
- MDT, Now available: the MDT Glass Touch Smart / Plus 4 inch, 16 October 2026.
- MDT, Glass Touch Smart Plus 4 inch product page.
- MDT, datasheet GTS-04TW.01S, Glass Touch Smart 4 inch, 04/26.
- MDT, datasheet GTS-P4TW.01S, Glass Touch Smart Plus 4 inch, 04/26.
- Merten, Technische Informationen KNX, 2016, on the spare pair and bus cable.
