Checking Coax Cables (Bnc, Thin Ethernet) - BEHA LanTest 50 Instruction Manual

The same error code appears, if e.g. cable 6 and 7 have a short-circuit.
This wiring error is detected by a simplified NEXT measurement. The Near
End Cross Talk (NEXT) (also horizontal attenuation) defines the side-to-side
crosstalk or excess of signal energy between the cable pairs within a data
cable. The electro-magnetic field of the wanted signal of a wire pair genera-
tes an interfering signal in a neighbouring wire pair.
5.3.2

Checking Coax Cables (BNC, Thin Ethernet)

This test is used to check coax cables for continuity and short-circuit.
Connect one side of the cable und test with the BNC test connection socket
(5).
Connect the other side of the cable under test with the BNC test connec-
tion socket of he coding plug (9a).
The test is starting by pressing the "TEST" key (1).
The LED pair _ shows the result, together with the 14-segment display (4).
If the cable is in order the display "1" in the 14-segment display (4) ap-
pears for correct detection of the coding plug. Additionally the green LED
(3) is illuminated. If the red LED (2) is illuminated, the wiring is incorrect
or the cable is defective.
The further error messages do not have to be considered, as the instrument
carries out the remaining pairs, which are not there – this is also valid vor
the shielding.
Terminating resistors having been mounted are also detected as short-cir-
cuit and are displayed
After termination of the measurement, the instrument switched off automa-
tically.
35