30
Capacitance test
Use of capacitance test function can judge the length of lines.
If there is no bridge tap or waterish logged, we can get the
length from the test result of the capacitance.
Calculation formula: L=C
ab
/C
O
(Km)----------------------------------
②
②
: C
ab
for capacitance test result (nF), C
O
capacitance result
(nF) per kilometer.
Commonly used telephone cable capacitance per kilometer:
C
O
= 51nF.
If the tester prompts “out of range”, that means capacitance
out of range or the cable have faults, please re-test after
checking the lines.
Conducting this test, if the lines have voltage (voltage more
than 2V), the tester will prompt “voltage!”, and then return to
the test menu. This means the line has electricity and cannot
test the capacitance, please check the line and retest after
cutting the electricity.
The interface as following:
Insulation test
