BMS (Building Management Systems) are systems for the integrated
management of all the technological functions of a building, including access
control, safety, fire detection, lighting, intelligent elevators, Air-Conditioning.
The development of these systems has meant that control systems made by different
companies often need to be connected together, and consequently not only is a
common electrical standard required, but also a common language, or communication
protocol.
The resulting advantages of such solutions (simpler and more efficient management
of the building from a single control station, reduction in running costs, possibility
of statistical analysis of all data, immediate identification of and response
to faults and alarms) amply justify any extra cost of the individual devices.
Today not only are the quality and the reliability of the instruments important,
but also the degree of external connectability they can offer.
ADVANTAGES
Comply
CAREL has always designed its controls to communicate with other systems,
and has constantly followed the evolution of technology in the communications
sector.
For this reason, CAREL controllers, both parametric and programmable,
can now:
- be integrated into systems consisting of instruments made by different
manufacturers, with which they share information;
- be managed remotely via modem and via Internet, even by simply using
a browser;
- inform authorised personnel, wherever they may be, of any alarm situations,
including by SMS message.
"Proprietary" protocols, that is, those developed separately
by individual companies, are now being replaced by "independent"
standard protocols promoted by international organisations. Nonetheless,
a single dominant standard has yet to emerge, and for this reason CAREL
offers a wide range of solutions that allow its controllers to be connected
to the main BMS currently available. With its two new products Web-GATE
and PlantVisor, CAREL can also interface its controllers
to Ethernet™-TCP/IP networks, allowing the use of technology developed
for the Internet for the transmission and display of the data.
CAREL protocol and DLLs
For specific applications, CAREL can supply its proprietary protocol specifications,
so as to allow the protocol to be integrated into the supervisory system
itself.
If the CAREL protocol is to be integrated into a 16 or 32 bit Windows
application, CAREL also provides a DLL that handles communication with
CAREL controllers.
In technical terms, a DLL, standing for Dynamic Link Library, is an executable
file containing a series of functions that can be used by external modules.
Specifically, using the services provided by the routines contained in
the CAREL DLL, supervision software can be created to receive and send
data to and from all CAREL peripherals without needing to know the protocol
that these use.
CAREL can supply the DLL or the protocol and the related information following
an agreement with the company or body developing the software.The request
for the CAREL protocol/DLL in fact requires the signing of a declaration
detailing their precise use and binding the user to keep the information
received confidential.
Monitoring, signalling and telemaintenance The connection of the controllers into networks means that one
single supervisory station can manage the parameters and information required
to identify the status of the devices present and the parameters corresponding
to the applications or the processes being controlled. The data collected
(temperature graphs, fault signals, service requests), which can be displayed
by the user simply and quickly, are saved and can be made available to
other functions.In addition, authorised operators can access the information
saved via a remote connection, in order to analyse or check the correct
operation of the systems. They can consequently modify the control parameters,
modify or force the operating modes, or directly manage any actuators.
When required, it is the system itself that alerts the appropriate service
centre.
Distributed control
The use of both open and standard systems allows the development of distributed
intelligence systems for more efficient and effective control.
CAREL solution
CAREL has implemented compatibility with all the protocols that are emerging
as the “de facto”standards in the world of HVAC/R and intelligent
building management, and that are consequently used
in the leading BMS: LonWorks®, Modbus®, BACnet™, TCP/IP,
SNMP, and METASYS®. CAREL has also developed systems
to interface to other proprietary protocols, above all the TREND protocol.
Connection mode
CAREL controllers can be connected to the BMS in the following ways:
- directly, without any intermediate devices, thanks to the ability of
the pCO sistema series controllers to select the protocol being used;
- by connection to a gateway, that is, an external device that makes the
hardware standards compatible and converts the CAREL proprietary protocol
to the protocol used by the BMS;
- integrating the driver that manages the CAREL proprietary protocol into
the BMS.
Event synchronisation
The individual control actions can be coordinated so as to be performed
at certain times and in certain ways, in order to minimise any negative
effects on the overall system.
One example is the division of the loads due to the defrost operations,
with a consequent reduction in the peak power consumption.
