Toshiba Strata AirLink, Руководство по установке

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Maintenance and Troubleshooting
Troubleshooting
Strata AirLink Installation Guide 5/00
87
4. Disconnect the BSIA from power.
5. Disconnect the 25-pair cables from P1 and P2 on the BSIA.
6. Disconnect the transmit and receive cables from the Base Station and connect them into each
end of the RJ-11 line adapter.
7. Set the multimeter to the ohms scale.
8. To check the distance to Base Station 1, connect the multimeter probes between pins 20 and 46
of the 25-pair cable that connects to P1 on the BSIA. If no reading or a high resistance is
reported, measure between pins 20 and 21. A reading should register at only one of the pairs
and must be less than the values listed in
Table 28 .
9. Based on which pins returned a valid reading in Step 8 , check readings between the following
pairs:
♦ Valid reading pins 20/46 – measure pins 21/45
♦ Valid reading pins 20/21 – measure pins 45/46
The readings between the measured sets of pins should be similar.
10. To check the distance to Base Station 2, connect the multimeter probes between pins 24 and
50. If no reading or a high resistance is reported, measure between pins 24 and 25.
Note
A reading should register at only one of the pairs and must be less than the values listed in
Table 28 .
11. Based on which pins returned a valid reading in Step 10 , check readings between the following
pairs:
♦ Valid reading pins 24/50 – measure pins 25/49
♦ Valid reading pins 24/25 – measure pins 49/50
The readings between the measured sets of pins should be similar.
12. If the multimeter reports no reading or high resistance, check the readings between any of the
other pins specified in Steps 8 ~ 11 .
If readings after performing Step 9 are correct, the transmit and receive pairs are probably
reversed or shorted somewhere in the installation. If not, there are open connections
somewhere in the installation; check and correct all punch-down connections and repeat
Steps
8 ~ 11 .
Table 28 Cable DC Resistance
Input
Power
Wire
Gauge
Maximum DC Resistance
Allowed for 2,000 feet
Line 22, 24, or mixed 98 ohms
Local
22 66 ohms
24 104 ohms