EXFO CableSHARK P3 VF/DSL Cable Qualifier - Manual (Page 147)

CableSHARK P3 User Guide
135
Selecting the RESISTANCE test from the Test Type menu one further parameter will appear:
Resistance
(ohm/mile or
ohm/km): See Table 8.7.1A for more information. See Appendix B for more information on
loop characteristics.
Please check with the cable manufacturer for specific details concerning the
cables capacitance constant. The Resistance Constant is used to calculate the
length of the cable based on the Resistance measurement. The following table
lists the most common values.
Metric (mm) AWG ohm/mile ohm/km
0.40 PE 451 280
0.405 26 PIC 439 273
0.50 PE 288 179
0.511 24 PIC 276 172
0.60 PE 198 123
0.644 22 PIC 174 108
0.90 PE 88.5 55
0.912 19 PIC 86.6 53.8
Table 8.7.1B – Resistance Constants –
Metric & AWG Wire Gauges (0Hz/DC, 20
°
C or 70
°
F)
Please note that cables containing any impairments including bridge taps
may severely affect the distance results based only on resistance. It
should be noted that a TDR test will provide the most accurate
determination of the length of a cable.
The function button command selection at the bottom of the DMM Tests Setup menu consists of five options
available to the operator. The first three options (EDIT/SELECT, SELECT PREVIOUS, SELECT NEXT)
enable the modification of the test parameters (residing near the upper part of the screen). In addition,
CABLE TESTS and MAIN MENU. For some options for which a numeric value must be entered, only three
options may appear: EDIT/SELECT, CABLE TESTS and MAIN MENU.
To select an appropriate test, it must first be highlighted with the cursor. A specific test can be highlighted by
moving the cursor to the desired parameter with the Cursor Pad UP/DOWN arrow buttons. The following are
brief descriptions of each of the function button options:
EDIT/SELECT Pressing the function button corresponding to EDIT/SELECT invokes a menu
wherein a desired parameter can be highlighted by using the Cursor Pad
UP/DOWN arrow buttons and/or the function buttons corresponding to PAGE
UP and PAGE DOWN (should they exist). Press the function button
corresponding ENTER to select the highlighted parameter.