A Practical Guide to Particle Counting for Drinking Water Treatment - Chapter 20 docx

... display for the affected particle counter. The left-hand indicator is for commu- nication alarm, and the right-hand indicator denotes a data alarm. The combination of the main alarm display and ... real-time data in the same package, as each display can be configured in one of the three modes. Several other options are available, such as manual or automatic scaling for the data (vert...

Ngày tải lên: 18/06/2014, 19:20

... Data Broadwell, Mike A practical guide to particle counting for drinking water treatment/ Mike Broadwell. p. cm. Includes index. ISBN 1-5 667 0-3 0 6-9 (alk. paper) 1. Particle counting (Water treatment ... D.C. A Practical Guide to Mike Broadwell for Particle Counting Drinking Water Treatment © 200 1 by CRC Press LLC 6 A PRACTICAL...

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... Packaged Treatment Plants Packaged treatment plants, as touched on above, are prefabricated plants, which are more cost-effective than ground-up plants for smaller applications. A packaged plant ... removal. (Courtesy of Pacific Scientific Instruments, Grants Pass, OR.) 28 A PRACTICAL GUIDE TO PARTICLE COUNTING manufacturers of packaged treatment plants employ particle c...

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... in-house calibration will never be practical. 2. Particle Counter Calibration Verification Verifying calibration is an easier and more practical step for the water plant operator. Only a couple ... at a time. If a spare is available it can be rotated into service. The maintenance log should be kept up- to- date, and calibration stickers displaying the date of calibration p...

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... PRACTICAL GUIDE TO PARTICLE COUNTING The disadvantage to this approach is that the particle counter data are collected and displayed separately from the other plant data, requiring separate training ... second alternative is the direct interface of the particle counters to SCADA using serial data communications. All count data, as well as status and alarm information, are t...

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... alters the approach to particle counter application. There are many ways in which grab samplers make particle counting more difficult to apply, and a few areas where they are advantageous. Again, ... case of online particle counting, trending the grab-sample data with other plant parameters will add to its value. If these data are available in a usable file format that can be...

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... detected and measured if it produces a signal with a minimum 2 to 1 signal -to- noise ratio. B. SIGNAL -TO- NOISE RATIO All electronic instruments are subject to various forms of “noise,” or random, meaningless ... Part III the actual manufacturer’s product offerings are presented. The chapters for Parts II and III are designed to run in parallel, to allow for easy cross-...

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... 82 A PRACTICAL GUIDE TO PARTICLE COUNTING The cell window materials vary in optical quality. Small imperfections in the material diffuse the light and are a source of resolution and sizing ... reflected back into the laser, it can disrupt this process, and cause variations in the beam intensity. This is another reason that aluminum flow cells are anodized a dark color, as the...

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... called a voltage comparator input stage. The more complex approach involves analog -to- digital (A/ D) conversion. 1. Voltage Comparator A comparator is simply a small circuit that “compares” an ... typically communicated every minute. The comparator provides a simple way to convert the particle size information from an analog pulse to a digital count value. It is a very...

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... voltage range of a chart recorder or SCADA analog input is 1 to 5 V. A 250 Ω resistor is required to convert a 4 to 20 mA signal into a 1 to 5 V signal. Another benefit of the 4 to 20 mA current ... loop have voltage inputs. According to Ohm’s law, voltage is equal to current times resistance. All that is required to convert the 4 to 20 mA loop to a vol...

Ngày tải lên: 18/06/2014, 19:20