XL-12000S
MANAGED, HIGH-SPEED NETWORK MODEM USER GUIDE
APPENDIX C: MEASURE LINE LENGTH
TUT SYSTEMS
65
Appendix C: Measure Line Length
Measuring Phone Wire
1.
Use a cable scanner or an ohmmeter to measure the lengths
of phone wire that will connect the modems. When using an
ohmmeter, short-circuit one end of the phone wire and measure
the resistance between the two wires at the other end.
Figure C.1 Using an ohmmeter to measure the length of phone wire.
2.
Multiply the resistance by 20 to find the length of the wire in
feet. For example, 600 ohms would indicate a cable length of
about 12,000 feet: 600 x 20 = 12,000 (+/-). This formula works
for 24-gauge phone wire.
600
OHMS
Short Pair
Together
Ohmmeter
Punchdown
Block
Punchdown
Block
