K-Test
Use this function to find the approximate distance to a resistance fault when both wires in a single pair are faulted at the same place, and a separate good pair or a single loop conductor is not available.
Resistance Check
Before you start the K-Test measurement, use the Resistance function to measure the resistance from both sides of the pair to the reference conductor.
The resistance faults must be common to the reference conductor.
One fault must be at least twice as “heavy” as the other fault (e.g., 5kΩ is twice as “heavy” as 10kΩ).
The sum of both faults must be at least 100 times the loop resistance of the pair (for instance, if the loop resistance is 50Ω, the fault sums must be 5kΩ or greater).
The K-Test first makes a measurement with the far- end “open” (the strap disconnected).
And then repeats the measurement with the far-end “closed” (the strap connected).
You may choose to use a “far-end switch” to open and close the far-end. The 3M KM Box Model 1162 is recommended for this application. The 965DSP will automatically send tones on the blue and yellow leads to communicate with the 3M KM Box (far-end switch).
The far-end can be manually opened and shorted during the test. However, be aware of timeout issues that may occur.
K-Test Setup
The K-Test Setup screen is identical to the RFL Setup screen. Press the [Setup] key to change the gauge or temperature.
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