Building control
Our company deals also with the installation and putting into operation of building control devices. We perform major works for the implementation of the air technical automatics of TESCO hypermarkets.
The building control and automatics system installed by us provides almost unlimited possibilities in the fields of operation, checking and control. The system may be applied in small, detached houses or in large building complexes as well. It is capable of serving and performing not only the typical HVAC (cooling, ventilation, air conditioning) tasks, but also all other building functions such as the handling of lighting and other electrical devices as well as the performance of fire protection and safety tasks.
Our building automatics and control system installed may be divided into three levels:
- management level, automatization level and field or final device level.
The operator workstations of the management level are connected via telephone-line or Ethernet to the automatization level. With the help of the program with graphic surface we can gather information about the status of the system and may change its operation, as well as collect statistical data. Furthermore we can carry out energy optimization with the help of a program and integrate other external -systems, too. - On the automatization level the automatic controllers communicate with each other via LON busses. Every station is equal ranking. Among the regulators we can find compact regulators, in which the I/O modules are positioned within the regulators, and extendable regulators, which are connected to the modules through P-busses.
- On the level of the final devices room regulators, sensors and the elements of external systems (3rd partition) can be found, with which the communication is realized through an adapter.
Compact automatic station
Freely programmable compact regulator for the HVAC and the building control systems. It ensures effective operation for frequently used applications. They may be used for 12, 22, 36 or 52 modules. The regulating station: maintains direct contact to the devices of the area; it is capable of fulfilling management tasks; operates also alone or it may be connected to a system together with many other devices; it can be remote programmed; room sensors may be connected to it; its communication is carried out through a LON-buss. This freely programmable automatic station is able to continuously control system-specific and application-specific tasks and take appropriate measures. The device is appropriate also for the execution of the following management tasks: Alarm management with route marking within the whole network. Alarms may be divided into three levels: simple, basic and increased alarm with monitoring the safety control and the automatic alarm; calendar function, timing; execution of trend tasks; possibility of remote access; access protection within the whole network, with individually definable users profiles and categories. The communication of the device corresponds to the international BACnet protocol. It communicates peer to peer via an open bus system with the other automatic stations.
The inputs of the device
The universal inputs can operate as passive and as active inputs as well, as voltage-free contact to the indicator tasks; The digital input accepts permitting signals and functions as a counter The outputs: The analogue (universal) outputs adjust regulating values or function as binary switches. The digital outputs can switch an alternating voltage of maximum 250 V and a current of maximum 2 A.
Technical data
The regulator functions with 24 V . 20% alternating current at a frequency of 50 or 60 Hz. Due to heat effect, an automatic restart takes place. It has a Flash and a RAM memory. Its cycle time is maximum 1 second. The deterioration period of the memory is 10 years and of the starting battery 4 years. The device operates appropriately at a temperature between 0 and 50 oC and at a relative humidity of 85 %. Its weight is ca. 1,250 kg.
The extendable regulator
Freely programmable automatic regulator communicating on a P-bus with I/O modules, to which 64 resp. 128 units may be connected with the help of one resp. two bus cables. The controller may be applied for HVAC or building control systems. It is capable of fulfilling different management functions, such as alarm, timing, trend functions, remote control, sabotage protection. It is able to perform the same tasks as the compact controllers mentioned in the previous chapter. It communicates with the I/O modules on the P bus on the basis of addressing, which may be between 1 and 255, with a direct voltage of 23 V. It may be directly programmed with a computer through a coupler RJ45 or RS232 or through a LON bus with an operator unit. It operates with alternating voltage of 24 V at an amperage of maximum 4 A. The communication with the modules is carried out at a direct voltage of 23 V and 9600 bit/s. It can operate at a temperature between 0 and 50 oC and at a relative humidity of maximum 85 %. The longest P-bus section may be 50 m, while the length of the whole P-bus is 300 m.
The external partition controller
The controller is the device used for the fitting or installation into the external system also called third partition system within the building automatization and control system. The device solves the fitting of the equipment and the system of the third partition to the automatic level with coupling through BACnet, which surveys and checks the external partition, be it HVAC, lighting, PLC or something else. Besides it also possesses protocol functions and may be freely programmed as an automatic station, but it has no physical in- and outputs. Checking and communication with the third partition are carried out with the help of a program. The device has a BACnet (a coupler RJ45 or a twisted wire pair coupler) and one series interface as well.
In the topology of the system, the device communicates in three directions:
- It maintains connection on the LON bus with BACnet communication to the other elements of the system;
- it has a direct connection to the computer running the program;
- and it communicates with the devices of the third partition through the given bus (e.g.: Modbus, P-bus).
Network coupler
It is a router communicating with BACnet protocol between the LON and the Ethernet network. It has to be applied always when it is necessary that the automatic stations communicate also with the Ethernet network. In this case the controllers are connected to each other and the router through a LON bus having a BACnet Broadcast Management Device object. This device communicates through the Ethernet network with the control computer or an other router, and through this with other automatic stations and controllers. A static IP address, a subnetwork mask and a default gateway has to be given to every BACnet router while choosing the gateway. DHCP is not supported, the BACnet communication is carried out through the static UDP port. The number of the UDP port arises during the choice of the gateways. At most ten BACnet gateways may be provided with BBDM objects.
