Discrete sensors

The unique measurement challenges in polymerization then may be summarized as follows vague control and measurement objectives, difficult sampling, discrete sensor output, large dead times and sampling intervals, off-line analyses, large measurement errors and high noise levels. 

Multiple discrete sensors are connected in series to a single input and the sensors all monitor the same process condition (for example, motor overloads). 

Direct-wired systems have the discrete sensor directly connected to the final element. This technology often provides minimal diagnostic coverage, so the testing interval may have to be decreased. 

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