LANTEK User Manual - Ideal Industries

Chapter 3
Structured Cable Field Calibration and Testing
Resistance Test
This test measures the loop resistance of each pair of wires. The test is performed to
ensure total loop resistance does not exceed recommended limits. Results are
displayed with resistance in ohms for each pair and a comparison limit for the cable
type.
Resistance Errors
Figure 3-12: Resistance Test Screen
All four pairs of a network link should have approximately the same resistance. Pair
resistance that exceeds the limit is indicated as a failure. The maximum limits in the
default tables are based on the maximum length limit of the link or cable segment.
Troubleshooting Resistance Problems
Problem: Excessive Resistance
Probable Causes
Mismatched cable types.
Poor punch block connection.
Poor RJ-45 termination connections.
Wire pair has a tap (never done).
Cable damage.
Shorted cable.
Other Tests Affected Test Possible Result
Wire Map
May fail.
Attenuation
May fail.
NEXT
May have false readings.
Capacitance
May fail.
Problem: One wire pair has a very high DC loop resistance, others are normal.
Probable Causes
Poor connection points.
Cable damage.
Connector blades not fully piercing wire insulation.
Worn Connector
Other Tests Affected Test Possible Result
Wire Map
May fail.
Attenuation
May fail.
NEXT
May have false readings.
Capacitance
May fail.
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