Associated Research HYPOTULTRA III 7620, Operation And Service Manual, Page: 20 / 148

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integrity of that connection.
Compliance agency requirements vary on how different products are to be tested. Most
specifications call for test currents of between 10 and 30 amps. Test voltages at these currents
are typically required to be less than 12 volts. Maximum allowable resistance readings of the
safety ground circuit are normally between 100 and 200 milliohms.
If you are testing a product that is terminated in a three-prong plug, you are required to perform
a continuity or ground bond test on the ground conductor to the chassis or dead metal of the
product.
1.6.4. Run Test
All manufacturers of a product that runs on line power normally need to run the DUT (Device
Under Test) after final safety testing so that they can verify the functionality of their products.
In addition to running the DUT to test its basic functionality, many customers also require some
basic test data to be recorded while the DUT is powered up. A Run Test System allows the
product to be powered up immediately after the safety tests are completed with a single
connection to the DUT. Measurements that are commonly made while the DUT is running can
include Amperage, Voltage, Watts and Power Factor.
1.6.5. Line Leakage Test
The Line Leakage test is one of many product safety tests that are normally specified for
electrical products by safety testing agencies such as Underwriters Laboratories (UL) and the
International Electrotechnical Committee (IEC). The line leakage specifications vary as well as
the method in which the measurements are taken depending upon the application or function of
a product and the standard to which the product is being tested.
Current Leakage or Line Leakage tests are general terms that actually describe three different
types of tests. These tests are Earth Leakage Current, Enclosure Leakage Current, and Applied
Part Leakage Current. The main differences in these tests are in the placement of the probe for
the measuring device. The Earth Leakage Current is the leakage current that flows through the
ground conductor in the line cord back to earth. The Enclosure Leakage Current is the current
that flows from any enclosure part through a person back to ground if it were contacted by a
person. The Applied Part Leakage Current or Patient Lead Leakage Current is any leakage that
flows from an applied part, between applied parts or into an applied part. The Applied Part
Leakage Current test is required only for medical equipment. All of these tests are used to
determine if products can be safely operated or handled without posing a shock hazard to the
user.
Line Leakage Testers provide the capability of meeting the line leakage test specified in the
following standards; UL 544, IEC 950, UL 1950, IEC 601-1, UL 2601, UL 1563, UL 3101,
IEC 1010 and others. The Line Leakage test, is a test which measures the leakage current of a
product, through a circuit that is designed to simulate the impedance of the human body. The
simulation circuit is called the Measuring Device (MD). The instrument has five different MD
circuits, selectable through the menu, which are representative circuits designed to simulate the
impedance of the human body under different conditions. The impedance of the human body