Signal conditioning has been around since the dawn of instrumentation and the requirement of taking measurements in the process plant. Much standardisation in measurement implementation has been introduced over the years for the sake of improved consistency, reliability and compatibility. Performance issues like sensitivity, accuracy, linearity and resolution are all givens in today's signal conditioning instrumentation.
What is new about new generation signal conditioning is that less is needed to do more.
This is certainly true in the case of Omniflex, which offers a wide range of signal conditioning capability that is implemented by the use of a small range of products. Omniflex has achieved this by working at finding ways to reduce the cost of ownership of signal conditioning for the user. At a quick glance, most signal conditioning modules look the same. But the following factors need to be considered in order to make a wise decision:
* Installation costs.
* Spares stock holding.
* Re-calibration costs.
* Reliability.
* Plant safety.
Omniflex has taken all of these factors into account in the design of its Omniterm 'B' series range.
Users can select a solution from the following product groupings to meet their performance and budget requirements:
Loop isolators
This is a typical challenge that relates to all plants no matter how old or new. The elimination of ground loops in analog 4 to 20 mA signal loops is the key to reliable and accurate measurements. There are Omniterm products that can solve these system problems. Whether all that is needed is the isolation of a transmitter from its power source, or the splitting the loop into two for the addition of data acquisition or monitoring.
Signal transmitters
The latest conversion technology combined with software configurability makes Omniterm products among the most accurate and versatile in their class. Universal inputs keep installation costs down, as well as reductions in spares holding and re-calibration costs.
A single transmitter is capable of accommodating inputs: thermocouples, resistance (RTDs), millivolts, DC voltage and DC current - and outputs: DC voltage (bipolar), DC current (bipolar), pulses out (linear integration).
Limit alarms/trip amplifiers
A range of alarm modules is available from simple limit alarms with manually adjustable set points to software configurable units capable of rate-of-change alarming direct from the sensor input.
Computation
While computation is generally performed by the scada, PLC or DCS on the plant, there are often instances when the user has a few analog signals that require manipulation or computation - and it would be handy to be able to process those signals directly in the plant. Omniflex offers modules designed to solve those tricky special functions required in certain processes, where the sensors require to be conditioned according to a more complex mathematical formula. Available functions include deviation, addition, subtraction, multiplication, linearisation, rate-of change, peak, valley, ratio, track-and-hold, etc.
Safety systems - IEC61508
IEC61508 is a standard being adopted for many industries and the requirements are such that the individual components of a system need to be analysed for compliance within the context of the safety system and its safety life cycle. The Omniterm 'B' series are compliant with a SIL 1 rating, making them easy to apply in safety critical applications saving time in the Haz Ops study phase of a project.
| Tel: | +27 31 207 7466 |
| Email: | [email protected] |
| www: | www.omniflex.com |
| Articles: | More information and articles about Omniflex Remote Monitoring Specialists |
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