Handheld Test and Measurement Instruments
'Form follows function.” The phrase originated with American sculptor Horatio Greenough and was popularized by architect Louis Henri Sullivan, but its wisdom also applies to product design. As the need for portable test and measurement equipment grew, manufacturers of these devices initially learned that the box was the optimal shape for containing and protecting the inner workings.
'Form follows function.” The phrase originated with American sculptor Horatio Greenough and was popularized by architect Louis Henri Sullivan, but its wisdom also applies to product design. As the need for portable test and measurement equipment grew, manufacturers of these devices initially learned that the box was the optimal shape for containing and protecting the inner workings. Whether beautifully finished wood, cast or formed metal, black phenolic resin, with or without handles or wheels, form indeed followed function.
Microelectronics, component miniaturization, and advanced materials/molding techniques, however, have put old equipment in new forms: smaller, lighter, rugged, faster, and more accurate. In this case, form no longer had to follow function.
In an online survey, conducted by Control Engineering and Reed Corporate Research, industrial users involved in specifying, recommending, and/or buying handheld test and measurement equipment indicated their technical requirements and preferences and purchasing habits. Their responses showed similarities to, and some surprising differences from, the previous survey conducted in 2002.
Who measures what
Of those specifying, recommending, and buying handheld test equipment, 82% said they used them for in-plant requirements, 5% used them for OEM (resale) market applications, and 13% purchased them for in-plant and OEM requirements. Applications varied. Thirty-six percent used testing devices in continuous and batch processing applications, 24% for utility services, 15% for discrete products manufacturing, 10% for continuous processing, 9% for batch processing, and 6% for other applications (see accompanying pie charts).
Most respondents use handheld test and measurement equipment for in-plant requirements. The largest percentage uses the devices in both continuous and batch processing applications.
Regardless of application, measurement use trends show some change over the past 4 years. Electrical parameters are still measured most, with 36% saying they use these devices for this purpose. Calibration accounted for 14%, and electrical power measurements for 14%. (In the previous survey, electric power measurements were part of a broader electrical parameters category. It included position/dimension values, force/torque measurements, and acceleration, accounting, at least in part, for the high 61% score in 2002.) This year, the “big four” process variables maintained their 2002 rankings with temperature at 8%, flow at 3%, pressure at 3%, and level at 1%. The remaining discrete manufacturing variables and event frequency were interspersed among them. The accompanying chart shows the detailed breakdown.
Use of electrical power measurement devices shown in this survey reflects today’s soaring energy costs. Although a majority of electricity is generated by coal, still a relatively cheap commodity, pollution regulations have increased power plant operating costs. Portable electric power measurement helps engineers evaluate the impact of energy-efficient retrofits and conversation efforts.
Single use versus multifunctional
Multifunctional handheld test and measurement tools offer real productivity advantages. A meter that can take several measurements makes it easier for a technician to cover the plant floor quickly. But this year’s survey shows some changes in use of multifunctional tools over the previous one. In the variable measurement area, the popularity of multivariable devices dropped, although they are still favored over a single function meter. In the area of calibration meters, however, use patterns were reasonably steady, with multifunctional devices remaining more popular than single function devices although their earlier lead decreased slightly. Multifunctional analytical meters experienced the greatest change. Dominance of multipurpose devices in this area evaporated over the last four years, putting use of single and multipurpose meters in this survey at virtually the same level.
Handheld test and measurement equipment is most commonly used to measure electrical parameters.
A number of factors may have contributed to the relatively sudden popularity decline of multivariable devices. According to Jonathan Rowe, product manager, transmitters for Invensys Process Systems, Measurements & Instruments Div., choosing the type of instrument to use is being complicated by the growing number of options available. Although a trend toward single-purpose test tools seems to be emerging, he observes, many users still prefer multipurpose devices because they minimize the number of instruments they have to purchase, store, and maintain.
He adds that users “are finding that recent advances in the technology and sophistication of handheld devices for specific applications provide performance benefits that outweigh the negative aspect of having to maintain more devices. Some of the recent developments pushing the growing use of single-purpose test devices are miniaturization, whereby more computing power is available for handhelds, and the growing number of digital field instruments with which users can interact using handheld configurators and calibrators.”
Ranking performance factors
In this survey, users rated the following factors as “very important” in their search for the optimum handheld test and measurement device:
Ease of use;
Easy to read;
As in the 2002 survey, performance again trumped cost and availably, indicating that users want quality at almost any price. There is a limit to what companies will pay for handhelds, however. Bill Southard P.E., president of DST Controls, says, “Although most users of handheld test equipment say they want the best, the most accurate, lightest, and easiest to use device regardless of cost, things can change once the purchase request gets to the boss and the purchasing department. The boss wants the simplest handheld available that is suitable for the job. The user wants repeatability and accuracy. Purchasing wants to get three bids and to compare functions.”
When all is said and done, ease-of-use and cost top the decision-making list, adds Southard. “The accuracy of most handhelds today is plenty good enough for the marketplace,” he says. “We live in an integrated world. My list would read ease-of-data entry, ease of integration with database, cost, availability, and warranty. Accuracy/repeatability is usually enough and basic durability—with the exception of explosion-proof models—is expected.”
Form may follow function, but not if the present handheld test and measurement vendors have their way. The trend today appears to be to supply the controls community with many forms to do whatever function suits the measurement needed, be it single or multifunctional.
Handheld test, measurement products
Exclusive: Portable configurator blends flexibility, functionality
Foxboro HHT50 configurator for use with any HART or FoxCom-compatible field device integrates a Microsoft Windows XP operating system, Field Device Tool (FDT)-based software, and its developer’s standard PC50 configuration software in a PC Tablet chassis, providing flexibility and functionality in a portable device. Also available is a PC50 version 2.0, which supports USB connections along with new HART scan functionality and Foxboro CFT50 Coriolis flowmeter configuration capability. XP Pro Tablet PC operating system expands functionality beyond a specific-use PDA or similar handheld device. XP operating system also lets users share permissions for remote access and troubleshooting through a network connection.
HHT50 measures 8.5 x 11 in. and includes a 40 GB shock-mounted hard drive protected by a multi-layer magnesium housing with external bumpers. It is impact-protected to withstand 4-ft drops to a concrete surface, landing on any side, edge, or corner, and meets MIL-STD 810F for use in harsh environments. It operates in temperatures from -4 to 140 www.foxboro.com/instrumentation
Invensys Process Systems, Foxboro Measurements & Instruments Div.
Thermal imager for troubleshooting
Ti20 thermal imager is designed for infrared troubleshooting and predictive maintenance applications. It includes a portable noncontact radiometric camera that measures temperature from 14 to 662s 12,288 pixels, displaying the thermal image and temperature reading on a large color LCD. Users can adjust critical parameters, including emissivity, reflected temperature compensation (RTC) values, palette, level, and span, and high and low temperature alarms, in the camera or using the bundled software. www.fluke.com
Fluke Corp .
Digital pressure gages
DPGA and DPGW economic digital pressure gages have selectable engineering units. Up to 11 are retrievable via a digital pushbutton on the face, allowing the user to choose the units used in the field. Features include battery power with a 20-min auto shut-off for conserving battery life, a 4-digit LCD with finite resolution, and a pushbutton zero to reset the gages in the field if necessary. www.dwyer-inst.com
Dwyer Instruments Inc.
Four-channel data logger
HH309 four-input thermometer and data logger can store up to 16,000 records per channel at programming intervals. Unit comes with Microsoft Windows software (Windows 98, NT, XP, and ME) for displaying and saving data. Temperature range is -328 to 2,498 www.omega.com
Omega Engineering Inc.
Waterproof pH meters
Oakton waterproof, handheld pH 600-series meters feature a–2.00 to 19.99-pH range, expandable to 0.001 resolution, with accuracies to ±0.002 pH. Units store up to 500 data sets through automatic, manual, or timed collection. Time-and-date stamping meets GLP standards. Calibration capabilities include up to six points, a user-settable calibration-due alarm, and up to 15 buffer options with auto buffer recognition of USA, NIST, DIN, and PWB standards. Infrared IrDA wireless technology simplifies printing and PC downloading. IP67-rated meter operates with batteries or optional ac power adapter. www.coleparmer.com
Industrial safety VOM
Portable 260-9S/9SP Safety VOM, certified to EN61010-1, is suitable for testing most industrial and commercial installations and is rated for Category III-600-V applications. Device features self-contained ac current measurement capability to 10 A, available overload protection, and includes a test lead set with retractable banana jacks and carrying case. DC ranges have a sensitivity of 20KΩ/V and accuracy of ±2% of full scale. AC ranges have a sensitivity of 5K Ω/V and accuracy of ±3% of full scale. The device uses 1.5-V AA, 9-V (NEDA No. 13F, 1604A) batteries. www.simpsonelectric.com
Simpson Electric Co.
Portable data station
Datum-Y network-enabled portable multi-channel datalogger is reported to be the first to be certified for IPv6 (Internet Protocol version 6). It measures and records, in the field or plant, environmental data including temperature, voltage, current, power, vibration, speed, and rpm, and can use various communication media for alarms, remote data collection, or to change settings. It is housed in a compact, rugged case with detachable terminal block to wire easily up to 8 or 16 channels of thermocouple, RTD, or dc voltage inputs, including two digital inputs and one pulse input. Lithium-Ion rechargeable battery provides up to 8 hr of continuous operation, if ac power is unavailable. Model XL100-1 (8 channel) and XL100-2 (16 channel) portable data stations are equipped with a 3.5-in. color LCD monitor with wide angle viewing. www.yokogawa-usa.com .
Yokogawa Corp. of America
MSA Altair Pro Single-Gas Detector with replaceable sensor and battery measures toxic gas concentrations or percent oxygen, displaying data on a large, clear, backlit LCD. Device features enhanced dust and water protection, resists impacts and RFI, and includes an alarm system. Adjustable alarm setpoints and data logging are offered on all units. Other features include simple, intuitive operation; small rugged design; IP67 rating; and current sensor options for carbon monoxide, hydrogen sulfide, and oxygen. Gas detector is part of the MSA Stellar Series, which features single- and multi-gas instruments. www.msanet.com
Cable, fiber certification
WireScope Pro category 3 to 6A and LAN cabling and fiber certification tool is an upgradeable handheld platform said to provide the fastest Category 6 cable and fiber certification available. Designed to meet present and future cabling standards, it supports cable certification to TIA Categories 3 to 6, Augmented Category 6, and Category 7 limits. It can also certify multimode and single-mode fiber and measure alien crosstalk. Device tests cables to full 10 Gbit/s compliance and requires no fiber swapping. www.agilent.com
Other information from Control Engineering related to handheld test & measurement instruments includes:
“Test, Measurement Device Purchases on the Rise”