Ekinex® thermal regulation in a corporate headquarter

Introduction

The present application is about a corporate headquarters, which comprehends multiple buildings with multiple usage destinations. Here, the KNX system controls lighting, shadowing and room/environment independent temperature control. Different needs brought to different heat exchange terminals: the actuator/controller EK-HE1-TP controls heating and cooling and is capable of controlling electro-thermal actuators or servomotors for zone valves in combination with thermostats or KNX temperature sensors.

Offices

The office building is equipped with an innovative and performing ceiling radiant panel system, chosen for its high level of comfort in both cold and warm season as well as its low noise level; it works in combination with a primary air system for dehumidification and air renewal. The hydraulic distribution serving the radiant panels is a 4-pipe system: hence, the actuator EK-HE1-TP was configured with outputs controlling the servomotors for each zone valve, thus safeguarding the mandatory interlock. This way, the active valve closes completely before the paired valve starts to open, thus preventing the cooling and heating fluids from mixing. The actuators are distributed in order to reduce connection lengths with the servomotors; this is possible thanks to the TRIAC output channels which guarantee low noise, thus contributing to the high acoustic comfort of all workplaces. All offices, meeting rooms and open spaces are equipped with room thermostats EK-EQ2-TP acting as temperature controllers: their two digital inputs are connected to a window contact and an anti-condensation probe. In larger environments and open spaces the regulation is carried out not only by the temperature measured by the room thermostat, but also by an auxiliary one, measured by a KNX pushbutton (normally used for lighting and shadowing tasks); during commissioning phase, a weighted average of the value has been calculated, thus optimizing the room temperature regulation.

Radiant ceiling panels with 4-pipe hydraulic distribution, on/off command of servomotors for zone valves with interlock function. Thermostats EK-EQ2-TP used as temperature and relative humidity regulator. Window contact and anti-condensation probe (in the environment) connected to the thermostat’s digital inputs. EK-HE1-TP used as actuator.

Restrooms

Restrooms are equipped with radiant heating elements connected to a classic collector-based distribution; anterooms and restrooms make a single zone. The actuator here serves also as regulator, controlling a servomotor for each zone valve; it receives the room temperature value from a KNX sensor, while setpoints and operating modes comes directly from the building supervision system. A dedicated line, supplied with hot fluid only, serves this specific part of the plant, which it only works through winter. The actuator EK-HE1-TP is programmed to automatically activate the electro-thermal actuators on a regular basis during summer, in order to prevent the valves from blocking due to their long inactivity.

Radiators, on/off command of servomotors for zone valves. KNX sensors to detect the environment’s temperature; EK-HE1-TP used as actuator/controller.

Warehouse

The warehouse is heated by industrial radiant floor panels, whose high screed is suitably reinforced to withstand the high loads due to the stationing and movement of goods. Here, heating has the purpose to maintain comfortable conditions for the workers and, at the same time, prevent the stored goods as well as the thermal plant from damaging due to low winter temperature. The actuator works in combination with KNX temperature sensors and acts also as controller. The radiant solution has been chosen for the environments’ high clearance: this is because a convection system could have led to excessive air stratification.

Radiant floor panels, on/off command of electro-thermal actuators on valves integrated in the distribution collector. Room thermostat and KNX sensors used to detect the environment’s temperature. EK-HE1-TP used as actuator/controller.

Focusing on the device

The actuator/controller EK-HE1-TP is a KNX device which extends the ekinex® range of solutions for temperature regulation, thus offering a high application versatility. The device can work either as a simple actuator in combination with ekinex® KNX room thermostats or as actuator and controller in combination with KNX sensors. It also allows a steady room temperature control in buildings where hydronic systems with heat exchange terminals or radiant panels are present. 

The actuator is equipped with 8 independent channels to command electro-thermal actuators or servomotors for zone valves. All output channels are equipped with TRIACs, which guarantee a high number of cycles – mandatory in sophisticated regulations – as well as absolute noise-free operation, thus allowing to be installed in any part of the building. The device can be either used for heating only, typically where heating elements such as radiators or heated towel racks are present, or for both heating and cooling, in combination with floor, wall or ceiling radiant panels. If the actuator is used in a 4-pipe heating/cooling system, its outputs are paired and then the number of independently controlled circuits goes down to 4. Each output channel can be controlled by an external KNX regulator (e.g. an ekinex room thermostat) or take advantage of its internal regulator in combination with a KNX temperature probe. An easy-to-use membrane keyboard allows to manually operate the device which is then completed by a signalling LED.

The configuration of the device is carried out by ETS (Engineering Tool Software) starting from version 4. The application program APEKHE1TP.knxprod can be downloaded free of charge from www.ekinex.com; it is available in Italian, English, German and French. In order to take advantage of all the possibilities offered by the device, an application manual including a detailed explanation on each configuration parameter is also available on the website.