Fresh design for smart building projects: Push-button and controller series KNX eTR

Feb. 25, 2021
A simplified user interface, robust design, and flexible programmability bring ease of use and elegance to wall-based controls.

The controllers and push-buttons of the KNX eTR series are switch-sized and flexible in their installation. The clear design language creates quick and easy access to KNX building technology. The real glass surface is elegant, hygienic and durable at the same time.

The controllers and push-buttons may be installed on the wall with or without a switch box. All devices of the eTR series are supplied via the KNX bus voltage, so only the KNX TP line is necessary for connection. At 82 mm × 82 mm and 12 mm installation depth, the size corresponds approximately to a normal switch. A temperature sensor is integrated in all devices of the eTR series, so that no further sensors need to be installed for room temperature control.

The KNX eTR M touch buttons are flexibly programmable. For example, as a light switch, for dimming, to raise and lower shades or to call up scenes. The LEDs in the touch surfaces can be set individually, as feedback to a touch operation or as ambient lighting. KNX eTR M is available as a single, double or quadruple push-button. The area function is an extra for the multiple push-buttons: When several fields are touched, for example by wiping over them or briefly placing the hand on them, another function is called up. The area function is often linked to the main function for a room, e.g. to switch on the light when passing by.

Printed icons immediately show that the KNX eTR MultiTouch push button is used to set light, temperature and shading. Three times three areas are available in total. For light, the following could be set: Dim darker on the left, dim brighter on the right and switch on the lamp icon in the middle. The scene control included in the KNX device application offers further possibilities. The call-up of the scene can be assigned to one of the areas, e.g. "Dimming and ambient lighting" when tapping on the blind symbol.

In the temperature area, thanks to the LEDs, it is immediately visible whether one has set cooler or warmer than the standard setpoint temperature. Also heating is visualised by a red LED and cooling by a blue LED. If the thermometer flashes, frost or heat protection is active. The control software for the heating and cooling system is included in the KNX device application. The PI controller can control single- and two-stage heating and cooling systems and switch between heating and cooling in combined systems. The reference is always the comparison between the measured actual temperature and the desired setpoint temperature.

With KNX eTR MultiTouch, too, the area function is executed when several touch keys are touched simultaneously.

The individual feel-good temperature is the focus of the heating/cooling controllers KNX eTR 101 and KNX eTR 201/202 Sunblind. The setpoint temperature is displayed in luminous digits and can be changed using the intuitively understandable "Plus" and "Minus" buttons. Here, too, the controller for heating and cooling is included in the KNX application. Models 201 and 202 have additional up/down touch surfaces for positioning sunshades or blackouts. sun protection or darkening. LEDs in the touch surfaces provide visual feedback, e.g. as long as a drive is moving.

So while the user interface of the KNX eTR series convinces the user with simplicity, many individual settings are possible in the application. Another helpful functionality is the mixed value calculation of the temperature sensor, which takes the value of another sensor if required and processes it into a room average. Logic modules enable simple AND and OR links. For example, the feedback of the LEDs in the touch surfaces can be prevented at night. And open window contacts can switch the temperature control to frost/heat protection mode.

The great flexibility at a manageable price level qualifies the series not only for private residential buildings, but also in particular for offices, buildings used by the public and hotels with a KNX building bus system.


Elsner Elektronik GmbH

+49 (7033) 30945-0


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