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Test resistance in the drop cable
Before connecting the bottom end of the copper Cat5e drop cable to the PSU or network
terminating equipment, connect it to a cable tester and test that the resistances between pins are
within the correct limits. If any of the tests fail, examine the drop cable for wiring faults.
Order the PTP drop cable tester from the support website
(
http://www.cambiumnetworks.com/support
) by completing the order form.
Perform the following resistance tests on PSU and AUX drop cables:
Measure the
resistance
between…
Enter
measured
resistance
To pass test,
resistance must
be…
Circle
“Pass” or
“Fail”
Additional tests
Pins 1 and 2
Ohms
<20 Ohms
(60 Ohms) (*2)
Pass
Fail
These resistances must
be within 10% of each
other (*1). Circle “Pass”
or “Fail”:
Pass
Fail
Pins 3 and 6
Ohms
<20 Ohms
(60 Ohms) (*2)
Pass
Fail
Pins 4 and 5
Ohms
<20 Ohms
(60 Ohms) (*2)
Pass
Fail
Pins 7 and 8
Ohms
<20 Ohms
(60 Ohms) (*2)
Pass
Fail
Pin 1 and screen
(ODU ground)
K Ohms
>100K Ohms
(*3)
Pass
Fail
Pin 8 and screen
(ODU ground)
K Ohms
>100K Ohms
(*3)
Pass
Fail
(*1) Ensure that these resistances are within 10% of each other by multiplying the lowest
resistance by 1.1 – if any of the other resistances are greater than this, the test has failed.
(*2) A resistance of 20 Ohms is the maximum allowed when the cable is carrying Ethernet. A
resistance of 60 Ohms is the maximum allowed when the cable is carrying only power to the
ODU (when Ethernet is carried by one of the other ODU interfaces).
(*3) This limit applies regardless of cable length.
