EEC SE 7430, Руководство пользователя, Страница: 18 / 106

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1.5.2 Insulation Resistance Test
Some "dielectric analyzers today come with a built in insulation resistance tester. Typically, the IR
function provides test voltages from 500 to 1,000 volts DC and resistance ranges from kilohms to
gigaohms. This function allows manufacturers to comply with special compliance regulations.
BABT, TÜ V and VDE are agencies that may under certain conditions, require an IR test on the
product before a Hipot test is performed. This typically is not a production line test but a
performance design test.
The insulation resistance test is very similar to the hipot test. Instead of the go/no go indication
that you get with a hipot test the IR test gives you an insulation value usually in Megohms.
Typically, the higher the insulation resistance value the better the condition of the insulation. The
connections to perform the IR test are the same as the hipot test. The measured value represents
the equivalent resistance of all the insulation which exists between the two points and any
component resistance which might also be connected between the two points.
Although the IR test can be a predictor of insulation condition it does not replace the need to
perform a dielectric withstand test.
1.5.3 Ground Bond Test
The Ground Bonding test determines whether the safety ground circuit of the product under test
can adequately handle fault current if the product should ever become defective. A low
impedance ground system is critical in ensuring that in case of a product failure, a circuit breaker
on the input line will act quickly to protect the user from any serious electrical shock.
International compliance agencies such as CSA, IEC, TÜ V, VDE, BABT and others, have
requirements calling out this test. This test should not be confused with low current continuity
tests that are also commonly called out in some safety agency specifications. A low current test
merely indicates that there is a safety ground connection. It does not completely test the 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 40 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.
1.5.4 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