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

Multiple displays allow for directcomparison of different data points, as well as comparison of historical data withcurrent data for the same sample points.. Scaling and Configuration Ch

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as well as in operational aspects.

Software is often the deciding factor when purchasing a turnkey system This isunderstandable, as the software is the most visible part of the system, and providesthe daily point of contact for the operator This is also true because so little isunderstood about the particle counting equipment It is our hope that this book willhelp to alleviate this problem At any rate, it is important to look closely at theparticle counting software, with consideration for the ease of use and access to theinformation, as well as the usefulness of the many features involved A plethora ofbells and whistles is not necessarily an indication of a more-advanced product Itmay be less important to have a fancy system than one that performs the basics and

is easy for the operators to learn and work with Other applications may require allthe advanced features available

We are not attempting to rate the packages described below, and particularcomments about the usefulness of certain features should be taken as opinions, whichmay not be applicable to every situation Our intent is to aid the reader in evaluatingthe relative importance of features, many which may not otherwise become apparentuntil months after the system is in operation These comments should only be taken

as a starting point Most of the manufacturers provide demo versions of their softwareprograms, and will gladly provide them to potential customers Take advantage ofthis and become familiar with the way these packages work Let other operators trythem as well, to get a broader perspective The computer expert in the plant mayreally like an intricate system, which will never be utilized properly by the rest ofthe operations staff

We also do not undertake to rate how effectively each of the features describedperform in day to day operation Software is constantly being upgraded, and is never

L1306/frame/pt03 Page 165 Friday, June 23, 2000 2:16 PM

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166 A PRACTICAL GUIDE TO PARTICLE COUNTING

“bug-free.” Problems encountered at the writing of this book may have been fixed

by the time the book is published

A OVERVIEW OF AVAILABLE SOFTWARE

1 Met One

Met One currently produces a package that they call Water Quality Software(WQS) It is available in four different configurations, named Insight, Vista, VistaNet,and VistaNet Server These are basically four different grades of the same package,with Insight designed for small systems of seven particle counters or fewer Insighthas fewer features (no backwash indication, for example) Vista supports up to 32particle counters, where VistaNet is a networked version designed for systems havingfrom 20 to 100 units VistaNet Server will accommodate up to 200 particle countersper server It is designed for large multiplant water systems

For simplicity, these packages will be called Met One WQS in the descriptionsbelow They must be operated under the Windows 95, 98, or NT operating system.Some older 16-bit versions are still in use, but should not be specified for newinstallations WQS was written in-house, and has an attractive and well-writtenmanual

It is intuitive and easy to use, which is fortunate, as the manual is functional butpoorly reproduced

3 ARTI

The newest program of the four reviewed is the ARTI Aquarius software Itsupports up to 32 particle counters Aquarius is a 32-bit program designed for usewith Windows 98 and NT It includes extensive context-sensitive help files and anadequate manual A unique feature is its ability to be run in different languages.Currently, English and Japanese are fully implemented, and the code can adapt toother languages The program will run under the language set up as the Windowsdefault, or can be set during program launch with a single-command line entry Asimple language translation utility is used for customizing the program for otherlanguage and character sets

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is a 16-bit program compatible with Windows 3.11, 95, 98, and NT No networkedsystem is yet available, but special programming is available to allow the package

to share data with some SCADA programs The program is easy to use and fairlyintuitive, which is good since the manual provides only minimal information Usersare on their own with the spreadsheet program

Some of older IBR systems use the AccuCount software developed by HiacRoyco out of a third-party SCADA package called Fix DMACS It is less functionaland more difficult to configure than the other packages SCADA packages aredesigned to be used for a wide range of processes and applications, so must be moreopen ended to allow for this It usually requires several steps to perform a simpletask with one of these packages The raw SCADA package is configured by theparticle counter manufacturer to perform the basic particle counting tasks If endusers want to change some things about the system, they may have to learn how toconfigure the SCADA package to do what they want This approach is expensiveand cumbersome, and has been largely abandoned in the industry For this reason,IBR developed the Intellitest software AccuCount is a 16-bit Windows 3.1 and 3.11package, which should be capable of running under Windows 95

B FEATURES

All the packages run under some version of Windows operating system, which allowsfor multiple programs to be operated simultaneously However, all of them recommendthat the data collection computer be used for just that, and that other programs be run

on other machines where possible This is a wise course to follow, especially with theprice of computer hardware being so low Larger systems should use networked machineswhere possible, so that reporting and data analysis can be performed on a machinedifferent from the one used for data collection, to minimize problems

All of the software programs provide trend plots, tables, status or current valuescreens, and event logs Alarms are displayed in various forms, and reports areprovided The major features of each package are presented below, with notablefeatures highlighted

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across the top of the display WQS and Aquarius provide icon-driven selections aswell, while TracWare and Intellitest use labeled buttons that are kept in the samelocation for each screen Consistency is important for ease of use, while the exactlayout and style may be more a matter of user preference

Two of the packages provide for multiple displays to be viewed simultaneously

packages provide only one screen at a time, although several forms of data may bepresented on that screen Up to eight screens can be displayed in Aquarius TheWQS software can provide up to four simultaneous graphs or data tables, depending

on the size and resolution of the monitor used Multiple displays allow for directcomparison of different data points, as well as comparison of historical data withcurrent data for the same sample points

Aquarius utilizes the standard Windows MDI (Multiple Document Interface), sothat the user can shrink or enlarge any of the data windows using the mouse Screensmay also be moved around and rearranged as desired Tool bar icons allow screens

to be tiled or cascaded with a single mouse click Met One limits graphs and datascreens to or full-screen size only Multiple graphs are shrunk vertically to fitthe display, but the horizontal size remains fixed The relative positions of thedisplays are also fixed, with the current data screen on the left-hand side of thedisplay, and the graphs or data tables on the right See Figure 20.2

IBR Intellitest utilizes a fixed screen with an upper and lower half The upperhalf remains fixed, and contains most of the buttons for selecting the various optionsand displays The lower half changes to provide those displays Buttons are dimmedand disabled when they do not apply to the current display, a feature that helpssimplify operation

2 Trend Display

As mentioned in previous sections, the trend display of data is the most usefuland informative All the software packages provide some form of trend display Inevery case, the vertical axis is used to indicate data values, while the timescale isdisplayed on the horizontal axis All of the packages provide different scales forboth axes, which are user selectable

a Scaling and Configuration

Chemtrac’s TracWare, although limited to a single trend display, provides vidual data scales for each of the four pens on the trend display See Figure 20.3.This is especially useful when trending particle counts along with an auxiliary input,such as turbidity Finished water turbidity is usually below 0.1 NTU, whereas particlecounts may be over 1000/ml or more Each of these trends can be scaled independently

indi-to provide good resolution The other programs use a single data scale for all pens,which can be set to linear or logarithmic In the above example, multiple graphswould be used to achieve maximum resolution with Aquarius and Met One WQS The vertical data scales on the TracWare program are adjusted up and down byclicking on the top or bottom scale value for the relevant pen The scale values can

3 4 ⁄

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Figure 20.1 Aquarius main display (Courtesy of ART Instruments, Inc., Grants Pass, OR.)

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also be set on the graph setup menu, along with a choice of colors for each pen Thislatter feature allows for consistent color codes to be used on multiple graphs whenthe same parameter is displayed more than once With the exception of TracWareand Aquarius, the other programs use set colors for each pen, which requires that thesame value be matched to the same pen on each graph if consistency is desired.Intellitest provides entry fields for the upper and lower scale ranges, which can beaccessed directly on the trend display A configuration menu for Intellitest, Met OneWQS, and Aquarius allows for choosing between log and linear scaling Met Oneand IBR provide an automatic scaling option, which adjusts the scale to the highestvalue displayed Aquarius and Intellitest feature “zoom” options, which let the userenlarge a part of the graph for detailed viewing Intellitest has a “grabbing” option,which allows any point on the trend line to be moved to the desired part of the display,automatically adjusting the axes for optimal viewing Aquarius allows the data in the

“zoomed” window to be moved around as desired See Figure 20.4

Intellitest allows for display of only one particle counter at a time The analoginputs connected to that counter may be trended along with the particle count data,which may be displayed as differential or cumulative counts versus time A histogramprovides counts versus size To view comparative trends, a commercial spreadsheetmust be utilized

The other packages allow for trending data points from anywhere in the systemtogether on the same display TracWare and WQS provide four pens per display,Aquarius and IBR Intellitest, eight All the packages use individual colored pens.All but TracWare provide individual line markers for black-and-white printing ofthe trend data

The pen selection is similar for the Aquarius, TracWare, and WQS programs.The latter two provide for up to 32 trend displays with any combination of datainputs or calculated (i.e., log removal) values assignable to any trend graph There

is no practical limit in the Aquarius software Each trend graph can be given a namefor easy reference Each sample point is given a tag name when the system is initiallyconfigured, and these tags are selected from a pull-down menu when setting upindividual graphs For particle count values, a separate menu is provided with theparticle size ranges All of the graphs configured are then available from a pull-downmenu, making selection simple The only significant difference between these pack-ages is that TracWare provides a set of eight buttons at the bottom of the trenddisplay which allows direct access to the first eight graphs configured There arealso up and down arrows that allow the user to scroll through all 32 graphs insequence See Figures 20.5 and 20.6

b Time Period

The amount of data collected by each system varies, with some programs viding user settings to control the sample period This, in turn, impacts the timeperiod that can be displayed on a single trend display, as well as the resolution ofthe data TracWare collects data every minute, and there is no user option forselecting a longer or shorter sample period Data are displayed on the trend graph

pro-in pro-increments of 1, 5, 10, 15, 30, and 60 mpro-inutes This value is chosen by clickpro-ing

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on right and left arrows beneath the trend display In all, 120 sample points can bedisplayed on the screen, allowing for time spans from 2 to 120 hours (5 days) Thecurrent value is always displayed on the far right side of the display, and the displayshifts to the left when a new sample is recorded A separate historical program hasbeen added that allows the user to set the time period desired to view the data stored

Figure 20.5 TracWare trend graph setup screen (Courtesy of Chemtrac Systems, Inc.,

Nor-cross, GA.)

Figure 20.6 Aquarius trend display (Courtesy of ART Instruments, Inc., Grants Pass, OR.)

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Three trend display modes are provided When set to display updated values,the time frame can be adjusted using right and left arrows at the top of the display,but each click shifts the data by only 1 min Clicking directly on the span valuebrings up an entry field where a longer span can be input A second mode provides

a scroll bar, which allows rapid scanning of the last 2000 samples stored The currentdata are not updated in this mode The third mode is used to retrieve long-termhistorical data Beginning and ending sample times and dates are input into entryfields Met One combines historical and real-time data in the same package, as eachdisplay can be configured in one of the three modes Several other options areavailable, such as manual or automatic scaling for the data (vertical) axis Verticaland horizontal grids can be added, and a graph title and label for the vertical axiscan be added for printouts Trends can be displayed in two or three dimensions, andthe traces in thin or thick line widths See Figure 20.8

Figure 20.7 WQS rapid storage configuration (Courtesy of Pacific Scientific Instruments,

Grants Pass, OR.)

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Aquarius displays up to 240 sample points ranging from 1 hour up to 5 days.For time displays larger than 4 hours, any of four different data presentations areavailable For example, a display of 24 hours would mean that each displayed samplepoint is spaced 6 minutes apart The display can be set to show the actual countvalues taken every 6th minute, or the minimum, maximum, or average of the samplescollected during that 6-minute period In fact, each of the four can be displayed inseparate windows for the same data point, allowing for direct comparison of thefour options This feature is especially valuable for looking at time periods spanningseveral days

3 Tabular Data Display

Tabular data are useful for viewing actual values in relation to trend graphs Acertain event or unexpected change in data can be viewed in tabular form to get amore exacting representation of the data The data value should be presented alongwith the sample time to allow for pinpoint measurement of the time of the occurrence.Aquarius, WQS, and TracWare provide tabular data in a method closely tied totheir trend-graphing functions The Aquarius trend graph can be directly changed

to tabular data by double-clicking the display (and visa versa) WQS provides asimple option on the graph configuration menu to allow the display to be switchedbetween trend and tabular data The Rapid Storage works the same as for the trenddisplay, so some columns may have more data than others If the Rapid Storage isengaged, the data will be displayed at 1- or 2-minute intervals for the affected datapoint, while the other points will show data only at the normal data collection rate.See Figure 20.9

TracWare provides for 32 tabular displays, configured in the same manner as thetrend graphs, with the exception of pen selections Eight data points can be placed oneach table, and can be set to display data in increments of 1, 5, 10, 15, 30, and 60min Up to 240 values can be displayed, allowing for time spans ranging from 4 hours

to 10 days The latest value appears at the top, with older values descending downward

Figure 20.8 WQS trend graph configuration (Courtesy of Pacific Scientific Instruments, Grants

Pass, OR.)

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MANUFACTURER’S SOFTWARE 177

A vertical scroll bar is used to view values extending below the viewing area Just likethe graph display, eight buttons at the bottom of the screen allow for direct access tothe first eight data tables, and arrows allow for scrolling between all those configured.These eight buttons are not tied to the same data points as those used for the graphs,unless configured in that manner by the operator See Figure 20.10

Aquarius, WQS, and TracWare provide easy methods for comparing databetween sample points The long vertical tables with eight values side-by-side inAquarius and TracWare provide an easy way to compare multiple data points over

a long time span, while the multiple displays in WQS allow for quick comparisons,although only four values are presented side-by-side, and the gaps from the RapidStorage may make time comparisons a little less direct These systems allow fordisplays to be configured quickly, so that points of interest can be placed on thesame display with a few strokes of the mouse Figures 20.11 and 20.12

IBR Intellitest only provides tables for current values To view historical tabulardata, the spreadsheet option must be used The spreadsheet can be activated fromthe main menu of the program, providing integrated operation Macros are availablefor some common spreadsheet programs

4 Status Display and Alarms

Aquarius and TracWare provide the most complete single-status display, giventhat all the current values for eight particle counters are presented on a single display

Figure 20.9 WQS tabular data display (Courtesy of Pacific Scientific Instruments, Grants Pass,

OR.)

Tiêu đề	Manufacturer’s Software
Trường học	CRC Press
Chuyên ngành	Water Quality Management
Thể loại	Book Chapter
Năm xuất bản	2001
Thành phố	Boca Raton

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