Instruments for Electrical
Safety Testing . . . Since 1936
Benefits of Using a Scanning Matrix for Multi-point Testing
Associated Research, Inc
Introduction
Recent advances in electrical safety testing technology have made complying with safety
agency standards far easier and more efficient for electrical product manufacturers. From
microprocessor controlled instruments to all-in-one testing equipment, safety testing
instruments with intuitive features help increase efficiency, reduce operator error, and
improve safety around the production environment. While the majority of production line
managers and test operators have upgraded their old transformer-in-a-box testers to new
models, some are either unaware of the benefits of incorporating new multi-point testing
technology into their testing procedure, or are not yet convinced that this technology can
improve performance on the production line. In this article we will discuss some of the
benefits that multi-point testing technology can provide, and how manufacturers can
ultimately improve throughput, efficiency, and accuracy during production line electrical
safety compliance testing.
Introducing the Scanning Matrix
From appliances to medical devices, most electrically powered products must comply
with safety agency standards that specify some combination of hipot, ground bond,
insulation resistance, and line leakage tests. More advanced applications not only require
these tests, but also specify that they be performed at multiple points on a product’s
chassis. The nature of multi-point testing can drastically increase setup time, contribute to
operator error, and reduce production efficiency. Until recently, test operators were
forced to painstakingly change connections and re-wire test leads in between each test,
but all the negative aspects of multi-point testing can be eliminated by using a scanning
matrix.
Scanning matrices are instruments that act as high voltage and/or high current relay
switch boxes. These types of devices take the output of a piece of test instrument (hipot
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Instruments for Electrical
Safety Testing . . . Since 1936
tester, ground bond tester, etc.) and apply it to different points on the DUT without the
need for additional connections or rewiring. By providing all of the necessary relays
inside the instrument, test operators no longer need to manually change test connections
in between test steps.
Scanning matrices can help to increase throughput on the production line because the test
operator need only configure the test instrument and scanner once prior to testing. This
saves time as the test routine does not need to stop in order for the test operator to
manually change test connections from one test to another. Scanning matrices also
increase operator safety and minimize damage to the DUT. Since test operators are no
longer required to change test leads during testing or in between test steps, the chance of
incorrectly wiring the test leads (the leading cause of injury or DUT damage) is
eliminated.
Scanning Matrix Options
Scanning matrices can be located internal or external to the safety tester. Internal
scanning matrices are usually included as an option on certain types of testers, while
external scanners are sold separately in stand-alone chasses. Automation capability is also
another means of classify scanning matrices, as some are controlled directly from the
front panel of the testing instrument while others can be controlled by a PC. Internal,
external and automation-ready scanning matrixes have advantages that depend on the
application for which the instrument is being used.
Internal Scanner Matrices
Some safety testing equipment, such as the Associated Research model 7650 (see Figure
1), includes a built-in scanning matrix for easy multi-point hipot and insulation resistance
testing. This kind of instrument is perfect for cable harness and motor manufacturers that
must subject multiple test points to high AC or DC voltages.
13860 W Laurel Drive, Lake Forest, IL 60045 U.S.A. • Phone: (847) 367-4077
Fax: (847) 367-4080 • E-mail: info@asresearch.com • http://www.asresearch.com
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Instruments for Electrical
Safety Testing . . . Since 1936
Figure 1: AR Model 7650 w/ 8-Channel Internal Scanning Matrix
The 8-high voltage channels can be configured from the front panel of the instrument (or
through software which we will discuss later), and allow test operators to apply high
voltage between multiple points quickly and easily without the need to purchase any
additional equipment. An electrical safety testing instrument with an internal scanning
matrix is a cost-effective solution for manufacturers with multi-point testing applications
that wish to increase productivity and improve safety.
External Scanning Matrices
Some electrical safety testing equipment may not include an internal scanner, but can be
configured to operate one. The Associated Research model 8106 (see Figure 2) can be
combined with a model SC6540 (see Figure 4) external scanning matrix to perform hipot,
ground bond, insulation resistance, and line leakage tests on products with multiple test
points from a single instrument. The SC6540 scanning matrix can be configured from the
front panel of the test instrument or through software. Figure 3 shows how to connect the
SC6540 to an OMNIA 8106. When used together, the test instrument and external
scanning matrix make test setup quick and easy and reduce the chances for operator error
or injury. An electrical safety testing instrument and external scanning matrix is an ideal
13860 W Laurel Drive, Lake Forest, IL 60045 U.S.A. • Phone: (847) 367-4077
Fax: (847) 367-4080 • E-mail: info@asresearch.com • http://www.asresearch.com
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Instruments for Electrical
Safety Testing . . . Since 1936
solution for appliance or medical device manufacturers that must perform multiple safety
tests at different points on each product.
Figure 2: AR Model OMNIA 8106
Figure 3: OMNIA 8106 w/ 8 HV –8 HC Channel SC6540 Modular Scanning Matrix
Automation and Modularity
13860 W Laurel Drive, Lake Forest, IL 60045 U.S.A. • Phone: (847) 367-4077
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Instruments for Electrical
Safety Testing . . . Since 1936
For manufacturers with complex test routines, the benefits of a scanning matrix don’t end
with direct front-panel control. Indeed, automated test routines that utilize both an
electrical safety testing instrument and accompanying scanning matrix are an economical
solution that increases production efficiency, reduces the risk of operator error or DUT
damage, and can improve performance exponentially. Most safety testing equipment
providers realize that manufacturers’workplace requirements and skill sets vary. That is
why models like the AR model SC6540 can be configured to work with a PC and any
number of automation interfaces, including GPIB, RS-232, Ethernet, and USB.
Figure 4: AR SC6540 Modular Scanning Matrix
Available software packages such as AR’s Autoware program make controlling the
instrument and accompanying scanning matrix quick and easy. Autoware allows the test
operator to configure multiple test routines, execute them, and store the test results on the
PC or a local network.
Another unique benefit of the scanning matrices like the SC6540 is their modular design.
Modular scanning matrices allow manufacturers to increase the number of scanner
channels to fit a particular application. With multiple channel configurations to choose
from, including 16 HV channels, 16 HC channels, and 8 HV and 8 HC channels,
choosing the right modular scanning matrix for any application is easy. This is especially
important when testing needs change and manufactures must upgrade their electrical
safety testing routine to include additional scanner channels.
13860 W Laurel Drive, Lake Forest, IL 60045 U.S.A. • Phone: (847) 367-4077
Fax: (847) 367-4080 • E-mail: info@asresearch.com • http://www.asresearch.com
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Instruments for Electrical
Safety Testing . . . Since 1936
Conclusion
Scanning matrices are an ideal solution for multi-point testing applications. With a
multitude of optional topologies available, it has never been easier for a manufacturer to
select the ideal instrument-scanning matrix combination for the job. Whether it is internal
or external, locally-controlled or automated, incorporating a scanning matrix into your
electrical safety testing routine will provide big benefits in productivity and safety.
13860 W Laurel Drive, Lake Forest, IL 60045 U.S.A. • Phone: (847) 367-4077
Fax: (847) 367-4080 • E-mail: info@asresearch.com • http://www.asresearch.com
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