Restricted accessResearch articleFirst published online 1988-04
A capacitance-based solids concentration transducer with high immunity to interference from the electrostatic charge generated in solids/air two-component flows
Electrostatic charge generated in solids/air two-component flows can cause significant errors in solids-concentration measurement systems based on capacitance techniques, and, in the worst case, can overload or even damage the measuring circuits. A transformer ratio-arm bridge capacitance transducer, incorporating synchronous demodulation and a noise attenuating input amplifier, has been developed for this type of application. The transducer has been tested on several solids-flow plants. It shows a very high immunity to charge interference and it is capable of withstanding large magnitudes of electrostatic interference without being overloaded.
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