Siemens Automation and Drives has developed two telecontrol systems based on high-speedlow-cost GPRS (general packet radio services) data transmission.
The Sinaut Micro communication system for simple telecontrol tasks is based on the Simatic S7-200 micro controller as well as the GSM/GPRS MD720-3 modem and the Sinaut Micro SC OPC server.
With up to 256 controllers per serverseveral thousand remote stations can be connected to the central control station by radio. For the telecontrol of larger automation tasks with Simatic S7-300 and 400 controllersthe Sinaut MD740-1 is used – equipped with an Ethernet connection as well as a GPRS wireless modemVPN (virtual private network) router and a firewall. Both new systems allow communication between the GPRS stations.
The new telecontrol systems are suitable for diverse wireless applicationsranging from miningsewage plantswater treatmentoil and gas pipelinespumping stations and traffic control systemsthrough to 'intelligent' advertising screenslighthousesticket machines and ATMs and distributed energy generation and distribution in wind powerphotovoltaic and district heating systems.
In previous systemsthe central control room accessed remote stations using a GSM (global system for mobile communications) modem. To do sothe operator either had to set up an expensive dedicated line or use a point-to-point connection charged on a time basis and with the frequent disadvantage of longer connection build-up times.
Compared with GSMGPRS offers up to eight times the data transfer speed and also maintains the connection ‘online’so the latest data can be transmitted to the central control on a permanent basis.
Costs are charged only in accordance with the transmitted data volume. This is more
cost-effectiveparticularly since mobile wireless vendors have been offering machine-to-machine tariffs for about two years now.
For more informationvisit www.siemens.com/sinaut
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