Manufacturers have no option but to fully test their systems, equipment and often products, to ensure they are operating within safety, productivity and quality specifications.
There is a wealth of tools, techniques and equipment to test weight, hardness, roughness or smoothness, speed, quality of signal, noise, voltage, current ?Â± the list goes on. The need for testing is increasing as manufacturers adopt more stringent production and output requirements in an effort to achieve ISO certification or to meet their customers’ increasingly tight specifications. Regulations around food and pharmaceuticals get more exacting every day.
While manufacturers and packagers could be busy testing materials, products, machinery and processes all day, the costs of testing run up quickly. Testing equipment and tools can be expensive; simple meters can cost about $100, while a multimeter with a graphical display can cost more than $1,500. Tools for troubleshooting computer networks start at around $20,000 and can go as high as $60,000. To top it off, the software used to operate them or to store and track the data they acquire can also be pricey. But what costs the most is the time required to do the tests. Not only does it take human resources to carry out tests and analyze the results, but if production machinery has to be shut down for the duration of the test, the costs add up quickly.
The latest generation of electronic testing tools attacks this problem from several directions. Today’s electronic tools are capable of testing many variables at one time, such as current, voltage, pressure, heat, strength and more; today’s products work smarter by delivering more accurate information more quickly; and more and more products are portable.
This new generation also pushes the "ease-of-use" idea a little further. Digital displays are easier to read and use more graphics, and they display acquired data in real time — as it comes in — without a significant delay.
Along with these improvements, more and more electronic tools can be connected to standard Windows-based computers. This allows large amounts of data to be stored, compared and analyzed later on. It also enables the tool to become part of a computer network; some tools can be used by a remote user connected to the Internet.
One of the most time-consuming aspects of testing and measurement is the need to conduct several different tests on one product, machine or process. This is why many manufacturers are releasing new products that measure or test several different variables at once. For instance, the Fluke 1520 MegOhmMeter tests insulation resistance and can also measure ac/dc voltage and Lo-Ohms. In fact, it’s hard to find just a voltmeter today; most also allow you to measure any number of different parameters at once.
Even something as seemingly low-tech as torque transducers are being designed to give buyers a wider range of uses: Norbar’s Torque Tools are designed for a wider range of transducers. This means a smaller number of transducers can cover a wider range of applications — in other words, you don’t have to buy as many transducers.
Smaller units such as Fluke’s 123 Industrial ScopeMeter, for troubleshooting machinery, instrumentation and power systems, is a combined scope, meter and recorder that can be carried in one hand.
Combining several functions into one device helps technicians work not just harder, but smarter. For instance, a technician can use Fluke’s 743 Documenting Process Calibrator to measure temperature in different types of temperature detectors or thermocouples. In addition to temperature, the 743 can be used to calibrate pressure, voltage, current, resistance and frequency — all in one tool.
Not only does this save money by reducing the number of testing or measurement tools you need, it also saves time — technicians no longer need to disconnect one tool and connect another one to take a different reading. One tool collects all the information needed.
While some testers have used hand-held, battery-operated units for a long time, more and more are being turned into portable units. The TorqueMaster Electronic Torque Calibration Analyzer (ECTA) is a portable, battery-operated torque measurement device designed for use with small, hand-held wrenches.
Fluke Networks’ ATM Analyzer is a portable analyzer that helps network professionals isolate and analyze problems or faults on ATM networks.
Manufacturing standards are getting more stringent in all forms of manufacturing, particularly due to government regulation in the food and pharmaceutical industries, but also for manufacturers striving for ISO compliance, or those whose customers are demanding adherence to ever-tighter specifications.
Controlling temperature within a close range is important in the food packaging and pharmaceutical industries, and requires not just accurate heating systems but also highly accurate testing and calibration equipment. Fluke’s above-mentioned 243 calibration system is a response to this trend.
But temperature is not the only element that needs careful control and measurement in today’s manufacturing world. Mitutoyo recently released what it calls the highest-accuracy co-ordinate measuring machine in the world, the LEGEX. In addition to reducing yaw and pitch error through the design of the CMM, the company has added vibration control — auto-leveling air springs which counter vibration from the floor ?Â± and temperature compensation, that counters slight deformations that may occur to parts of the machine, reducing measurement error.
Accuracy is not just a matter of maintaining the quality of the product, but also in keeping productivity up. For example, finding a break or fault in a fibre-optic cable is almost impossible without specialized equipment such as an optical time-domain reflectometer (OTDR). Sometimes, however, these units can only find such a fault within 100 metres. Fixing the fault can be next to impossible in a case like this.
Kingfisher Corp. has developed a "cold clamp" which works with Telstra Corp.’s OTDR. By placing the Cold Clamp on the cable in the general vicinity of the fault, the OTDR can reference the fault point to the Cold Clamp’s location, then find the exact fault position more quickly.
Sometimes, the very act of measuring something changes it. Adding electrical testing tools to a network, or even using testing tools on an electrical current, can introduce interference and field harmonics that can not only skew the readings, but introduce errors in processing.
New devices avoid this problem. For instance, Santronics’ Tel/Com 205 signal detector avoids interrupting digital or analog communications while it is monitoring or inspecting network services, or working in cross-boxes, splice cases, cross-connect frames and similar situations. The unit detects all digital signals or network activity in advance of testing the line, so it doesn’t disrupt the flow of data. The result is not only more accurate information, but reduced downtime.
Easier to use and analyze
One of the overriding trends in digital technology development is the creation of new tools that are easier to understand and use. Most companies now add larger screens that display more useful, and usable information. This not only helps to capture the data, but real-time displays help the user to analyze, understand and use the data to make decisions faster and more effectively.
The AC2000 Harmonics and Flicker analyzer from Laplace Instruments of the U.K. displays the harmonics in power systems up to 16 amps in different graphical formats; it also measures and displays flicker — the change in lighting power which can result in severe worker discomfort and even trigger epileptic fits.
The InSite Power Recorder from Reliable Power Meters Corp. measures and stores data on power quality, energy and power consumption, harmonics and other power parameters, and transfers the data to a PC where the company’s software displays graphical results in real time. For example, a power surge would show up immediately on a PC’s screen. This makes this unit and software and effective monitoring solution.
Mitutoyo’s SJ-301 surface roughness tester has a touch-screen for control and display of not only measurement results, but also for graphs for analysis. A built-in printer allows the user to store this data for later analysis.
MHH Engineering’s Electronic Torque Calibration Analyzer (ECTA) is a multi-function torque tester and calibrator for torque wrenches with an RS-232 C plug, which allows it to connect to a computer to download data for analysis.
Like so much else, electronic testing and measurement is moving to the Web — in different ways.
Adding an RS-232 port or some other form of communication port is cheap, and it’s the first step to wiring an instrument into a globe-spanning network of computers. The result could be spectacular.
For instance, Fluke’s Enterprise LANMeter Series is a set of instruments for managing and troubleshooting Ethernet and Token Ring-type computer networks. The WebRemote Control Option makes the system available through the Internet — which means you could troubleshoot a network in Calgary from Mexico City or Paris, as long as you had a Web connection and the right passwords.
Artesyn Technologies’ SimScope takes Web-based testing and measurement a step further. It helps the user to build a "virtual design lab" for testing various products, then view the resulting voltage and current waveforms at any point in the application.
Today’s manufacturing professionals are under increasing strain to do more with less: fewer people, less money, less downtime. The testing and measurement industry has responded with devices and software that addresses these needs.
By adding several functions to one unit — many digital meters, even weigh scales, can double as electronic calculators — manufacturers reduce the cost and time required to do effective testing. More accurate units also help to reduce the time needed to do an effective series of tests, while helping the user achieve closer tolerances and higher quality of product.
Adding graphing and display functions helps the user make better use of the data collected, and can have important long-term effects. When combined with Web access to tests and measurements as they’re happening, new tools are bringing the testing into the mainstream of plant management.
Scott Bury is an Ottawa-based freelance writer and a regular contributor of technical features to PEM. You can reach him at firstname.lastname@example.org.