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Design and Concept.

The electrical charge tomography process require continuous, consistent delivery of
solids materials with high accuracy of controlled flow rate and of course smooth running
operation. Suits with its requirement, such proper measurement system need to be cautiously
choose and indeed the electrostatic sensor will be the best option to run such smooth operation
for this system. The major advantage of picking up an electrostatic sensor which indeed because
of high sensitivity for concentration readings. According to some information obtained from
some research, if cross-correlation signal processing algorithms combined with it, it will provide
the most economical methods of measuring the velocity of solids in pipelines.
There are four main components in an electrodynamic tomography system. The
components are sensing part, signal conditioning system, data acquisition system and computer
that used for data processing and tomogram display. Solid particles such as dry powders will
generate electrostatic charge by friction within the pipeline wall. Each particle collides with
another particle in a wall, and consequently becomes charged up to a certain value of
electrostatic charge.
The derivation of signal produce from the random changes of induced charge arising
from the turbulent nature of the flow. The electrodes of the sensor will detect the motion of
electrostatic charge produce and eventually turn it into voltage signal by the electrodynamic
transducer. Below are an example of electrodynamic circuits.

Briefly this circuit operate by the current flow through the resistor which resulting in the
voltage, and consequently provides the input to the integrated circuit amplifier, connected as a
non-inverting voltage follower. The output of this amplifier is fed back to the negative input pin.

MC1458 and MC3403/LM324 bipolar products.While the output are being fed back to the negative input. . Below are some detail about the IC used for the signal circuit obtained from its datasheet. The output from this operation will be connected to a data acquisition system (DAS). The way this DAS operated are the signal output for each electrode will increase from zero volts to an equal magnitude of the electrostatic charge of the object which passing through the pipe. input offset currents and supply currents. Other than that the Zener diode contained in this circuit will prevent the large amount of voltage discharge which happened in a conveyor in way to protect the transducer amplifier from damages. the AC coupling used in this circuit will act as a gate which only let the AC signal to pass to the other stage of circuit. Basically. The IC is compatible with the industry standard MC1741. Besides that this IC provides a working operation temperature from 0 to 70°C which will be good advantage to work in such high-temperature circuit condition. On the other side of circuit. The IC used are TLO84CN. As mentioned above there is a an IC used in this circuit. All of this description mention can be found from the datasheet of Texas Instrument regarding about IC TL084CN. the TL084 of JFET input operational amplifier provides wide bandwidths and fast slew rate (the maximum rate at which an amplifier can respond to an abrupt change of input level) with low input bias currents. All the outputs reading will be captured by it and those signal will then be available for the image processing using the Matlab software. it will then be used as a guard voltage for the input circuit to the non-inverting voltage amplifier.

due to the 32 bit width and 33 MHz clock speed of the PCI bus.33 MB/sec maximum for the ISA bus. faster. PCI (Peripheral Component Interconnection) is standard interface developed by Intel. The KPCI-1802HC used in this system model is a high-performance PCI-bus data acquisition board for PC-compatible computers running Windows operating system. eliminating the need to set DIP switches on the board manually. triggering and gating modes and furthermore this model does support bus mastering.Meanwhile on the Data Acquisition System the KPCI-1802HC will be used as its data acquisition card along with the STA-1800HC as its screw terminal accessory. Upon system power-up or reset. or target mode data trasnfer methods. Through some research on the datasheet about this model. . This technology allows fast memory. disk and video access. Figure belows are the connectr pin assignment provides in its datasheet. direct data transfer to and from memory using bus mastering to bypass the CPU. it were made to be much simpler to gather analog data. data transfer causes minimal interruptions to normal processing. The screw terminal will also be connected to the sensor via its four 18-way ribbon cables. It do have some advantage for using this model which are :  The PCI-bus Plug and Play feature allows a user to install the data acquisition board without making manual system configurations. Some features in this model are flexible clocking rate. interrupt. Data transfer occurs at speeds up to 132 MB/sec rate for the PCI bus. read an output digital signals and provide analog stimulus. versus 8.  Cleaner. Besides. the PCI-bus Plug and Play feature automatically configures the board for the system.