99-2 A New Coloured Book is Born
MATES as a milestone
The "Metering And Tariff for Energy Supply" International Conference and Exhibition, held in Birmingham, UK, on 25 - 28 May 1999, will be attractive to many members of the DLMS User Association. The association itself will be present with a booth. Personal contacts, posters and leaflets will be the means to update the knowledge about ongoing work.
The Orange Book, First Edition
As announced in the last issue of "Metering International", the description of the object identification system OBIS is available to the members of the DLMS User Association. Not only general purpose objects (e.g. "number of days since last reset"), but also abstract objects (e.g. of class "association") are described. The structured description of application items translates to a number, which is nothing else but the object name, applied to an object of the Blue Book.
The Blue Book, Second Edition
The currently defined interface classes for meters and the relations between them are illustrated in this figure. They allow the exact description of the functionality of a quite complex meter for commercial and industrial usage. Of course, the definitions of the Blue Book First Edition, mostly devoted to simpler meters for residential use, are fully incorporated.
The tree structure of the figure gives some hints on the methodology used: All objects follow a base design structure. Data objects are mainly "visible" objects, where more complex objects inherit the structure of their simpler counterpart. Two association objects allow two different ways of establishing a safe connection between the meter and the master station. Register Activation, Schedule, Activity Calendar and Special Days Table master all the things time switches (in its largest sense) normally do. The Register Monitor triggers events linked to threshold values. The SAP Assignment informs about the assignment of logical devices to their service access point, and the IEC 1107 Setup handles down to earth things like baudrates, response time and the like.
The Green Book
The channel definitions are further advanced, they are a work item in IEC standardisation. A new release of the Green Book is to be expected in early autumn 1999. One important part of the Green Book has been revised. It is the Data Link Layer part, describing the use of HDLC, e.g. for communications using the telephone lines. Concerning tricky parts like broadcast and alarms, the Data Link Layer provides now relevant services. Important to know, the document bases on the newest draft standards of ISO/IEC 13293.