Electricity + Control October 2019

ANALYTICAL INSTRUMENTATION Product News

optical resolution, and - the conveyor speed, which will indicate the speed of response required of the instrument. Environmental conditions like smoke, dust and adverse weather should also be considered with regard to the required IP rating or accessories such as air purge collars for the lenses. On large coal and coke moving conveyors, the Raytek TX and MI3 systems have been used across South Africa and internationally. The large conveyor systems integrate the detectors into their trip systems so any spike in temperature from a hot spot in the product triggers an alarm. R&C Instrumentation has the knowledge and experience to advise customers on the right temperature tracking instruments and systems to suit different plant conditions. It includes fixed automation systems and portable infrared temperature measuring products in its product range. For more information contact

very fast response time (measured in milliseconds) and they do not make contact with the surface measured. This makes pyrometers ideal for conveyor belt monitoring. A pyrometer can be installed for each roller bearing, with the alarm set to trigger if the bearing temperature rises above a pre-determined threshold. The position and layout of belt sensors is determined by the design of the conveyor and the type of material conveyed. Essentially, according to R&C Instrumentation, an overlapping scan across the belt would present the best option. If a hot spot is detected, the system can trigger an automatic spray of a cooling agent or stop the conveyor if necessary. With many different models of infrared units available from the Raytek and Fluke Process Instruments ranges, it is easy to select the correct unit for each application. Factors to be taken into account in making the selection should include: - the temperature range considered safe for the product/production line, - the distance from the sensor to the product, which will determine the

often difficult to extinguish. This may be due to the flammability of the product conveyed or the properties of the belt itself. R&C Instrumentation notes that over the past decade or so, it has seen industries move towards a combined approach of fire prevention and fire detection. A heat detection system is used for early warning, and a fire detection system is installed for failsafe protection. The conventional ways of measuring temperature with contact probes like thermocouples and resistance temperature detectors (RTDs) or platinum resistance thermometers (Pt100s) are not suitable for this type of application. The problems of drag, friction and static generation rule out contact measurement. Furthermore, response time is critical on fast-moving conveyors. Slow response units allow hot spots to pass by the detector before an alarm condition can be detected. Non-contact infrared thermometers, also known as pyrometers, offer a suitable solution. Pyrometers have a

R&C Instrumentation. Tel +27 (0)11 608 1551, email: info@randci.co.za

With a combustion process in a furnace, for example, too little air will result in incomplete combustion, soot formation and a high carbon monoxide ratio. In contrast, too much air will mean incomplete combustion and unnecessary emissions and heat escaping up the flue with the exhaust gas. "As solid, liquid and gas fuels have varying calorific values, IMR analysers can store common and more unusual fuel factors in order to calculate fuel efficiencies," Fraser explains. With an IMR instrument, improvements in the fuel/air mix can be made easily. IMR combustion gas analysers are simple to operate, flexible, have wide measuring ranges and are highly accurate. These high-technology systems for measuring emissions have gained a respected reputation among IMR customers in the US and around the world. Fraser says RTS Africa is excited to introduce IMR Environmental Equipment to Southern Africa and he is confident that these industrial solutions will prove valuable in promoting the efficiency and profitability of a range of South African industry sectors.

For more information contact RTS Africa. Tel: +27 (0)12 433 6335 or visit: rtsafrica.co.za

RTS Africa now offers IMR on-line gas analysers and monitoring and recording equipment in Southern Africa.

Electricity + Control

OCTOBER 2019

39