Meters as well as the metering system are being provided by the Danish energy metering company, Kamstrup. The smart metering system is being implemented for the sake of a better energy management and better control with the meters in the far regions of the country. The system is currently being rolled out and the implementation takes place sequentially. Those who by now have received a new electricity meter can log in on the energy company's web portal to follow their consumption hour by hour.
The automatic meter reading system is an RF-mesh solution. The RF-mesh system has the obvious advantage of being independent of the power line grid, and thus uninfluenced by power outages or any other disturbances in the grid.
The RF-mesh network has furthermore been optimised for high performance.
Up to 300 meters are mutually connected in networks that communicate with an RF concentrator. The concentrator transmits the data via GSM/GPRS on to the energy company.
A high success rate on readings is attained by the self healing network and an efficient routing of radio signals. Each electricity meter is capable of routing the radio signal from up to 70 other meters which secures an always open path to the concentrator.
Single meters that are placed too distant for radio transmission, are being fitted with a point-to-point GSM module and a SIM card - transmitting directly to the energy company's central system. The concentrators collect data from heat, water and electricity meters all together. Heat and water meters use the electricity meters as routers.
The intelligent network can maintain itself by means of information that is already available in the network and by means of special features in the various network units as for instance the master list.
A master list contains groups of specific meters and enables the concentrator to recognise the signal strength quality and to identify any weak connections to these meters.
The concentrator then automatically searches for alternative routes to the specific meter. Via the meter reading system the RF concentrator can be configured to maintain the network more or less aggressively.
The master list also controls that the same meter is not read multiple times by different units in the same network.
For more information, enter √ at www.engineerlive.com/ies
Gert Skriver is with Kamstrup A/S, Skanderborg, Denamrk. www.kamstrup.com