In recent years, there has been an increased demand for remote monitoring of various geological and environmental measurements, particularly in the mining and engineering fields.
These measurements are often collected at remote, sometimes inaccessible, locations and need to be transferred to a computer where the data can be analysed.
Clever Devices and Designs cc (CDD), a Pretoria-based company, has developed the RLOG virtual RS-232 cable based on GSM/GPRS communications.
"By attaching one RLOG unit to the RS-232 port on the monitoring device and another to the RS-232 port on the data gathering computer, you set up a virtual RS-232 connection that can transfer data via the GSM/GPRS network over thousands of kilometres," says Cilliers Du Preez, applications engineer at CDD.
"The simple plug-and-play operation enables two-way communication between the devices as if there was a permanent cable linked between them. A physical RS232 cable has a maximum specified length of 30m, but with RLOG, you can literally run a 'virtual cable' around the world."
RLOG stands for "RS-232-Link-Over-GPRS", and is based on Wavecom GSM/GPRS wireless modem technology. It works for any device with an RS232 port in an area where there is GSM/GPRS coverage, and forms a permanent link that is connected 24 hours per day. There are no modem initialisation strings - you simply plug it in and the connection is established automatically by the RLOG unit. Baud rates from 300 to 115200 are supported.
The SIM card can be provided by any of the cellular service providers in South Africa, so that the customer can select the service provider with the best coverage in the particular area that the monitoring device will be deployed in.
"One of our clients, Cambrian, is a company that performs seismic monitoring during blasting at various mines around the country. Our customer had to travel to each mine to set up the seismic monitoring devices, and then re-visit each site periodically to download the readings," says Cilliers.
"With RLOG, there is now no need to travel to each of the sites after the initial installation, as data can be downloaded, in real-time, from each of the sites. This enables the analysis of the information to be done far more frequently, with better and more timeous reporting."
The uses of RLOG are widespread. Devices such as weather stations, temperature loggers and condition monitoring equipment, personal computers, alarm systems, telephone exchanges and vending machines are all examples of devices with RS-232 ports that could communicate via the RLOG virtual cable.
For further information, please contact Debra Hart at Clever Devices and Designs cc: (012) 667-4124, debra@cleverdevices.co.za, www.rlog.co.za
Wavecom wireless GSM/GPRS modules are available from Trinity Telecomms: 011 465-7377, enquiries@trintel.co.za, www.trintel.co.za
Trinity Telecomms (Pty) Ltd is a leading service provider focusing on the provision and support of end-to-end wireless connectivity solutions which enable wireless connectivity into the cellular network operators, as well as radio frequency for local area wireless connectivity. We are distributors for Wavecom GSM/GPRS/EDGE wireless CPUs and microprocessors, Coronis RF solutions, eRide GPS solutions, Active Guard RFID guarding solutions and a comprehensive range of peripherals and accessories. We offer comprehensive service and support options.
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