Rretrieval of properties from DLMS meters using GSM/GPRS technology in VC++ : Academic Small Sized Project

The main purpose of this project is the retrieval of electrical properties from DLMS meters using GSM/GPRS technology. These retrieved parameters will be used later for research purposes, checking condition of meter etc. The meters which uses DLMS protocol for communication is termed as DLMS meter. ## Deliverables **PURPOSE** The main purpose of this project is the retrieval of electrical properties from DLMS meters using GSM/GPRS technology. These retrieved parameters will be used later for research purposes, checking condition of meter etc. The meters which uses DLMS protocol for communication is termed as DLMS meter. **SCOPE** The DLMS specification specifies a data model and communication protocols for data exchange with metering equipment. It follows a three-step approach: * Step 1, Modelling: This covers the data model of metering equipment as well as rules for data identification. The data model provides a view of the functionality of the meter, as it is available at its interface(s). It uses generic building blocks to model this functionality. The model does not cover internal, implementation-specific issues. * Step 2, Messaging: This covers the communication services and protocols for mapping the elements of the data model to application protocol data units (APDU) * Step 3, Transporting: This covers the services and protocols for the transportation of the messages through the communication channel. **The Two 'Faces' Of DLMS** 1. The DL MS Object Model The basis of DLMS is an object oriented application model. It makes use of a method called 'abstract object modelling' .In this modelling technique abstract object types with their attributes and operations are described. In order to keep DLMS relatively simple, the DLMS model specifies only a few - five - object types. Each object type has a name, by which it may be referenced. These objects fall in two categories as follows: ? Resources: Data Set7 Task Invocation and Variables (Named Variables, Named Variable Lists and Message Boxes are all DLMS Variable types) are virtual objects representing resources of the real device. * The Virtual Application Association (VAA) object. This object is related to the communications feature, and represents an Application Association. 2. DLMS as Application Protocol This model itself is not a communication protocol, but provides an abstract structure modelling all communication related functions and serves as the foundation for communication protocols. It deals with the complexity by logically decomposing the whole communications system into smaller functional modules, called layers. One Application Process - the user ( or client ) of the DLMS model sends messages to the Application Process which contains DLMS Objects, and these messages are finally the invocations of operations of these DLMS Objects - and we get the communications view of DLMS. In specifying these messages and the way of handling these messages at the Application Layer, in terms of the OSI reference model we got an Application Protocol. The DLMS model ensures that a DLMS Client, after being connected to a DLMS Server, is able to communicate with this DLMS Server: it can get the list of DLMS Objects within the Server and also it can use any DLMS Objects of the server6. In these terms we can say that all devices built on the DLMS concept are interoperable. On the other hand the Client somewhere has to know the relation between the used. DLMS model - which is the only visible thing of the server - and the real objects being modelled in DLMS. If the Client ignores this relation, the whole thing worth nothing. For example imagine that the result of the reading of a DLMS Named Variable gives seven. Although it seems you get the required information - but if you don't know the meaning (is it the current tariff rate or the number of power fails since the last reading), you can't use this information, thus it worth's nothing for you. Companion Standards specifies this relation between real objects and objects /object attributes of the DLMS object model. Full interoperability may be obtained by specifying not only that you need DLMS, but also that which Companion Standard you require. **PROPOSED SYSTEM**** ** This project aims at developing software for communicating with servers for retrieving meter data through GSM/GPRS modems using VC++ Figure: Sending Meter Data Figure: Receiving Meter Data **REQUIREMENT SPECIFICATION** 1. Operating System: Windows 7/XP 2. Programming Language: VC++ 3. Microsoft Visual Studio 2008 4. DLMS Meter (any category) 5. Source and Bench connection. (240v) 6. Sim Card (with GSM/GPRS technology enabled) 7. GSM/GPRS modem REFERENCE SITES: **1. DLMS PROTOCL:** ? <[login to view URL]> ? [login to view URL] ? [login to view URL] ? <[login to view URL]> **2. IEC 62056** ? <[login to view URL]>