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The market is expanding in two directions—toward tools dedicated to fewer functions and toward sophisticated multifunction tools. Each type has its advantages.
On the one hand, to accommodate a broad market of end-users, some manufacturers are purposefully stripping various instruments down to the functionality that an individual needs for a particular application, offering a variety of units within a series, each with a distinct set of capabilities. These might range from basic to moderately industrial on through to sophisticated electronic models.
“Designing tools that meet specific job needs makes it much easier for users to pick out the best tester for them,” said Paul Heydron, product planning manager at Fluke Corporation. A complexity of controls that might be ideal for one technician’s job may be overkill for another. “Working with an instrument that is fast out of the tool chest, with numbers, buttons and switch positions that are easy to find and understand without referring to the manual saves an electrician time,” he added.
On the other hand, there are electricians looking for instruments that combine functionalities.
As electrical systems get more complicated and more sophisticated, electricians doing residential and light commercial work are starting to need capabilities in their testers—higher accuracy, higher display counts, capacitance, min/max, relative mode and other functionalities of that ilk—that previously were prevalent in tools directed to those involved in heavy commercial work, pointed out Chad Reynolds, product manager, test and measurement division at Ideal Industries.
And, as Gary Lalla, marketing manager at Greenlee Textron, pointed out, “Some electrical contractors want multi-purpose meters because they prefer to carry fewer instruments to the job site, thus increasing their productivity.”
Indeed, among various manufacturers, there is a trend of increasing functionally while decreasing cost. Manufacturers, in some cases, are redesigning their base multimeters for the average electrician, putting in chips that can do a lot more, often without any increase in price, or even with a decrease in price.
Just as cell phones now include a plethora of electronic functions pre-installed on chips, some meters also hold increased functionality as software pre-installed on tiny chips housed right in the meters. Manufacturers have, in some types of testers, replaced complicated electronics with software that automates the setting of various controls to achieve a specific test. “Already, this exists in various test instruments as specific algorithms or automated test routines—small software programs that perform a specific test—when a button is pressed. For example, a clamp meter that detects inrush current when a motor is started,” said Heydron.
Some meters now include the ability to troubleshoot and diagnose intermittent problems. The meters can be used with a data logger that records all events throughout the test period, even when the electrician is not on the premises. Also, some products display information in a way that allows the electrician to view the data much like he or she would view a graph to see both normal operations and disturbances.
Not only are manufacturers delivering meters that are more sophisticated, but they are also, increasingly, focusing attention on helping end-users use the products safely and competently. “There are always new electricians coming into the industry who benefit from learning about safety and proper use of the test instrument products,” said Lalla.
Some manufacturers design their products to the UL 3111 safety standards, and mark them accordingly, with the category rating (CAT I through CAT IV) on both the packaging and the units themselves. “Well-labeled products help the end-user buying at the counter ensure that the product they are going to use on the job is safe to use on the intended tests and that it will not cause harm to themselves or damage the meter,” said Lalla.
Increasingly, manufacturers are offering to take their education programs to trade schools and apprenticeship programs to teach new users about safety and about the proper use of testers. The programs, typically, delineate how to use various products in the generic sense and reinforce dictates of safe use of the products when working on live circuits to prevent injury or worse. Greenlee Textron, for example, includes reminders of common safety precautions that a worker might overlook, such as not to stand in a pool of water when making a test measurement, to wear rubber-soled shoes when working with electricity, and to wear safety glasses in case an arc occurs.
“Working with electricity can be very dangerous and the simpler the test instrument can be designed for the customer, they are going to feel more comfortable using it. And training is critical not only on correct use of the product itself but in general safety practices in the industry,” said Lalla. The AEMC Instruments Multifunction clamp-on meter Model F05 auto detects, measures and displays AC/DC volts to 600V (900V peak) and AC/DC amps to 400A (600A peak). It also measures resistance to 400kohms and continuity. The compact meter measures watts to 240kW, determines power factor and phase rotation and measures in-rush currents. In-rush currents, displayed in ½-, 1-, 2½-, 5- and 10-period increments, are detectable down to 500 micro-seconds. The unit is well balanced, rugged and can be operated with one hand, allowing any function to be easily selected and displayed.
Hioki's Model 3196 Power Quality Analyzer, with 13 MB of internal memory, is a lightweight instrument that packs a lot of functionality into a compact unit. Weighing just 4.4 pounds, this power quality analyzer can simultaneously and continuously record multiple phenomena without gaps in the sampling. The 3196 tests for transient over voltage, dips, swells, interruptions, unbalance and harmonics. The analyzer also records data of up to four channels at a fast sampling rate. The unit comes with an optional PC card, an RS-232C interface and a LAN interface. It is programmed with an HTTP server function that enables users to manipulate settings and acquire data via the Internet using a standard Web browser.
Designed for hard-to-measure locations with a detachable 45-inch sensor flexcord, the Meterman Test Tools LM631 digital light meter accurately measures light in lux and in foot-candles. Well suited for verifying plant and office lighting to meet workplace illumination standards and OSHA requirements, the ergonomically designed test tool, which uses a built-in CIE spectrum curve for accurate human eye response, features a large 3½-digit display and offers both “peak hold” and “data hold” functions. The portable, pocket-sized unit, measuring about 2½ inches wide and under 8 inches in length, weighs about 1 pound.
Amprobe’s portable, battery-operated multi-purpose AT-2004 Advanced Tracer includes an R2000 Receiver, the S2600 Load Signal generator (9-600v AC/DC), T2200 transmitter, two cord sets, an AD-1 adaptor, a clamp and a manual. The Receiver features two detectors in its tip tuned to pick up the electromagnetic signals (“short” mode) or electrostatic signals (“open” mode) generated by the other components. The unit, which is fully fuse protected and intrinsically safe, traces live conductors buried up to 13 feet, traces open wires for over a mile, and traces and identifies load-side equipment from the circuit breaker while energized.
Extech Instruments Clamp-on Power Datalogger, Model 382065 measures single-phase or three-phase power to 600kW. In addition to True Power, the battery-operated unit measures Apparent Power, Power Factor, True RMS Voltage and Current, Resistance, and Frequency. Combinations of measurements on the dual display include kW+PF, kVA+PF, V+A, A+Hz, or V+Hz. The built-in recorder datalogs up to 4,000 readings and a 25-point data memory viewable on the large four-digit LCD with fast 40-segment bar graph. Additional features include Peak Hold and MIN/MAX. A plug-in RS-232 interface module with software is available for downloading data to a PC.
AVO International’s battery-operated MEGGER DUCTER DLRO10X is a fully automatic digital low-resistance Ohmmeter that allows selecting the most suitable test current, up to 10 A dc to measure resistance from 0.1 micro? to 2000 M? on one of seven ranges. A menu system controlled by a two-axis paddle allows manual selection of the test current. The unit, fuse-protected to 600V, features visible warnings of high voltages present at the terminals and of current flowing in the test sample and real-time download of results and on-board storage for downloading to a PC.
Fluke Corporation 1520 MegOhmMeter features insulation-resistance testing (up to 4000 M?) in power system wiring with three output voltages (250V, 500V and 1,000V), AC/DC voltage measurement, and a Lo-Ohms function for continuity and ground connection testing. The battery-operated unit switches automatically to voltage sensing when connected to a live circuit with voltage over 30V and provides AC/DC voltage measurement up to 600V. Sporting a large backlit LCD with analog bar graph and digital display plus a last-reading memory display for insulation resistance and Lo-Ohms, the unit provides an “autodischarge” safety function to preclude user shock by residual voltage on tested circuits, and battery auto shut-off.
Greenlee Textron BLL-200 Professional Buried Line Locator traces 20 feet underground and provides depth readings up to 15 feet. The lightweight battery-operated unit, ergonomically balanced for comfortable low-stress operation, is UL listed and complies with UL 3111-1 Category III standards. Microprocessor-based circuitry delivers increased accuracy. The receiver may be used in active or passive mode. The clamp for inductive coupling, which can accommodate 3-inch conduit, is attached to the transmitter via a flexible 3-foot-long cable, for ease of use. The transmitter can be connected to live lines up to 600 volts AC and 300 volts DC.
Gardner Bender battery-operated Volt Check Voltage & Continuity Tester automatically measures AC/DC voltage, DC polarity and continuity without adjusting any dials. The instrument, which incorporates visual and audible indicators for increased assurance that the unit is working, has a built-in non-contact sensing head that automatically detects AC voltage without touching live wires. Constructed of impact-resistant ABS plastic, the instrument features overmolded rubberized housing, ergonomically designed for comfort and slip resistance. Soft-grip, heavy-duty probes snap into the back of the housing for storage. EC
The FELDMANS write for various magazines and Web sites. They can be reached at [email protected] or 914.238.6272.