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Specialty testers have their niches. By knowing when and how to use them, you increase their value. To help determine how specialty testers save time and effort, look to manufacturers and distributors, who are often keen on educating end buyers about a product’s inherent possibilities.
Most manufacturers filter hard copy information through their stocking distributors; more and more manufacturers supplement that with content-heavy Web sites that not only give product specs but also explain when and why to use the testers.
They might also run lunch-hour or after-hour seminars at distributor locations to familiarize potential buyers with their products. These provide easy, obligation-free opportunities for getting a look and feel of various products, along with detailed instruction on how to use them to best effect. Plus, you can ask questions and, hopefully, get immediate answers.
Typically, electrical distributors carry higher-end products in a category than big-box retailers and will generally offer more substantial sales help and after-purchase support.
Here are single- or multi-tasking tools that aim to simplify or streamline test within their respective domains.
Gardner Bender Circuit Tracker GET1200 circuit breaker finder identifies circuits on which electricians need to work without having to turn breakers off and on to locate them. This could be a welcome capability when a facility is occupied, and turning breakers off and on would be disruptive to occupants and equipment.
The two-part tester sports audible and visual indicators and consists of a transmitter, which plugs into the receptacle in question, and a battery-operated receiver and probe used at the breaker panel or fuse box, without requiring removal of any components. An optional adapter kit for locating lighting fixtures and switch circuits is available.
The sooner correctable situations along a circuit are found, the better. High-voltage drops and other problems with power can lead to energy waste, power inefficiency, possible damage to equipment on the circuit, and, at high amperes, increased chance of fire from excessive heating at high-resistance connections.
Ideal Industries, Inc. SureTest Circuit Analyzer 61-152 is a plug-in handheld circuit tester, with a digital display, that facilitates preventive troubleshooting on a live, loaded circuit without interfering with end user activities or causing disruption to equipment running on the circuit. The device applies a full 15- or 20-amp load to the circuit and then measures the voltage drop between the receptacle and the main panel.
It also verifies proper GFCI operations and tests the integrity of the wire all the way back to the panel, locating loose wire connections, bad splices or receptacles, or high-resistance or false grounds. With an optional adapter, the unit can also verify isolated ground presence. The model 61-156 also features True RMS and measures harmonic distortion.
Insulation resistance testers are useful for testing electrical cable or switchgear to ensure safety after initial installation of equipment (protecting against miswiring, damaged wiring, or defective equipment), and as part of predictive maintenance, to ensure that the insulation of various electrical systems is, after prolonged use, still safe.
Various insulation-testing procedures give an indication of the state of the insulation with respect to normal aging and state of deterioration or more serious or rapid degradation. If a problem is found, timely correction can extend trouble-free operation of that equipment.
Biddle High-Voltage DC Dielectric Test Sets (manufactured and marketed by AVO International), are suitable for checking the quality of any high-voltage apparatus, including cables, motors, switchgear, insulators, and capacitors, at both those stages in the equipment’s life, through over-voltage testing. Each unit can test DC dielectric strength and electrical insulation, ground circuitry and continuity, and three wire appliances.
An “acceptance” test can be performed after installation, but before putting the equipment in service, to make sure the cable was not damaged during installation, the terminations and splices were done correctly, and the equipment is performing efficiently. A “maintenance” test is typically performed on cable after service to see if the equipment is holding up. Each set includes 70, 120, and 160 kV test units, and is available either for analog metering or digital metering.
Fully tested to comply with IEC 1010-1, CAT III 600V overvoltage category, the Fluke 1520 MegOhmMeter multifunction insulation resistance tester provides all of the functions required for insulation testing and ground connection testing under EN 61557-2, 1997. Featuring a large, backlit LCD with analog bar graph and digital display, it tests wiring and motor insulation, ground connections, and continuity (via Lo-Ohms function).
The unit provides insulation resistance testing up to 4,000 M (Megohm), with three output voltages: 250V, 500V, and 1,000V. It switches automatically to voltage sensing when connected to a live circuit with voltage over 30V, and provides AC/DC voltage measurement up to 600V. The unit, which sports a last reading memory display, provides an “autodischarge” of capacitive voltage charges so users will not be shocked by residual voltage left on tested circuits.
Gardner Bender Circuit Alert non-contact voltage tester GVD-504A features non-contact voltage testing from 50 to 600 volts AC in a compact, easily pocketable, tool. The tester, which features a fully insulated probe tip that supports measurement without risk of contacting live electrical wires, utilizes both audible (beeping) and visual (flashing) indicators that signal the presence of AC voltage.
The device is handy for locating breaks in wires and voltage at receptacles, switches and motors, noted the company, and will quickly locate the hot terminal in any receptacle. An exclusive proprietary built-in “safe-test” feature indicates that the tester and batteries are operating properly. The tester, which is about 53/4 inches long and less than 3/4 inches wide, is covered by a five-year warranty, and carries a UL Listing.
Amprobe cable finder Model AT-3000 is typically used for detecting underground cables. The unit offers three selectable modes of operation, two of which facilitate tracing the cables, and a third that also determines the depth. The first mode—the power mode—detects 60 Hertz electromagnetic fields emitted by a current-carrying conductor.
The second—radio mode—is used if there is no current flowing in the wire, and detects the signal re-radiated by local transmitters (e.g., from radio stations). The third mode—transmitter (or generator) mode—incorporates use of the transmitter that comes with the tester. It is used when there is no live current, and it sends a signal into the ground, which is picked up by an underground cable, facilitating trace of the wire and supporting determination of cable depth.
Suited to applications in industrial environments, Greenlee Textron IPM-400 Process Calibrator is a multi-tasking industrial process meter that performs five different operations that might otherwise require five separate meters. The calibrator can be inserted as part of a process loop in a manufacturing component or process to determine if a particular electrical component, such as a valve in a bottle-filling machine, is functioning properly.
The unit has a minimum/maximum function to record low and high measurements and comes equipped with True RMS for accurate voltage measurement when harmonics are present. The calibrator, which sports a digital display, has AC voltage measurement capabilities and an auto-off function to preserve the battery’s life. Greenlee Textron also offers calibration service.
For installations that would benefit from observing power consumption or monitoring power conditions, and measuring the rate of equipment operation over time, data loggers are expedient additions to a test tool arsenal.
A trouble-shooting tool is useful if the client is having a problem with the quality of electricity this is suspected to be with a particular device or piece of equipment. AEMC Instrument’s new single-phase Power Quality Logger, Model PQL 100 measures, records, and logs electrical and power quality parameters. This tool is suitable for commercial, industrial, and residential applications.
Plugged in between a standard AC wall receptacle and the appliance, the tester monitors and records about a dozen variables at once, selectable from a suite of about 50 different functions, including volts, amps, power, total harmonic distortion, individual harmonics (from first to 50th), phase angle, and the reactive power volts, amps, reactive (VAR). Testing VAR, for example, could help clients in areas where utilities charge a penalty for high-reactive components by detecting a problem for the electrician to correct.
The recorded, accumulated informa-tion is downloaded into a computer and, via the data management software supplied with the logger, can be viewed as graphs or waveforms and in pre-configured or custom reports for printout and analysis.
HIOKI E.E. Corp.’s 3636-20 Clamp Logger collects AC current data, over time, for transfer to a PC, for printout, management, and analysis.
Suited for observing power consumption of plant facilities and buildings, the unit, which works with either the 9650 (maximum 100A) or the 9651 (maximum 500A) clamp-on sensor and downloads through a communications base, measures true root mean squared (TRMS) values and distorted waveforms. Its display function shows average instantaneous values from recorded measurements.
HIOKI E.E. Corp.’s 3637-20 data logger is designed for use with AC voltage and measures RMS values up to 600V. Suited to recording the status of equipment such as generators, it includes a function for displaying average values, as well.
Both loggers hook up to the HIOKI E.E. Corp.’s 3911-20 Communication Base, which can capture data from multiple loggers for transfer to a PC for analysis and management.
Relying on rods implanted into the soil, a grounding system provides a low-impedance path for fault currents to reach the earth. The lower the resistivity of the soil around the ground rods—the more readily the soil can absorb and dissipate the electrical current flowing into it—the better the system works. Various factors, including the type of soil and its moisture content, affect resistivity.
Before installing ground rod systems, and to help locate the best soil layer for optimized permanent moisture content, it is prudent to test the soil in several locations and at several depths within the target area.
ERICO Inc.’s Eritech Earth/Ground Tester EST201 is a portable ground tester that performs two-pole AC resistance measurement, three-pole ground/earth resistance measurements, and four-pole resistance measurement for determining soil resistivity.
The tester, which has a large light-emitting diode (LED) display, also measures noise voltage. The unit, which features a protective holster and splash-proof construction to help withstand harsh environments, comes in a kit with accessories, grounding tutorial book, and an operating manual.
The FELDMANS provide Web content for companies and write for magazines, trade associations, building product manufacturers, and other companies on a broad range of topics. They can be reached at [email protected] or (914) 238-6272.