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OneExpert DSL User's Guide
22052280, Rev. 015 April 2019
Chapter 13 Copper Testing
195
Measuring balance
Balance is a number representing the quality of the telephone
circuit and the degree to which the Tip (A) and Ring (B) conductors
are electrically thesame in their ability to cancel noise. The balance
measurement is used to identify poor loop quality or cable bonding
and grounding issues that allow excessive loop noise.
Balance is part of the MultiMeter test suite and can be launched both
from the Copper screen and from the MultiMeter screen. The Balance
tab includes Longitudinal Balance and Calculated Balance (Power
Influence and Metallic Noise).
1. Connect the Tip (A), Ring (B), and Ground (Earth) leads to the
line under test.
2. From the Copper menu or from the MultiMeter screen, press the
Balance tab.
3. The test begins automatically. Longitudinal Balance results appear.
Measuring PI (power influence), noise and balance
Power influence (Tip to Ground [A to E] and Ring to Ground [B to E]
noise) is the unwanted current inducted on the pair from power lines
and other AC sources. Noise is the unwanted current that the pair has
failed to cancel and which the customer hears as noise.
1. Press PI/Noise/Balance softkey to start measuring calculated
balance.
2. The test starts automatically. It measures the noise and power
influence and calculates the balance by subtracting the noise
from the power Influence.
3. Optional . Press the Ground Reference soft key to check the
ground reference.
4. Select Clear to restart the test.
5. To save the results to a report, use the Tray menu.
6. To learn what your results mean, see
“Longitudinal balance” in Chapter 15 “Test Results” .
Measuring PI, noise and calculated balance is complete.