Toshiba Strata AirLink DK40i, Руководство по установке и обслуживанию

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Fault Finding
Station Cable Continuity Check
14-8
Strata DK I&M 6/00
Ohmmeter Test
Check the continuity of the cable run between the KSU/cabinet and digital or electronic telephone
with an ohmmeter.
➤
To perform the ohmmeter test
1. Disconnect the DSS console, electronic or digital telephone.
2. At the MDF, remove the bridging clips.
3. At the MDF, place shorting jumper wires between the T and R of pair #1 (green-red), the T
and R of pair #2 (black-yellow) and the T and R of OCA pair #3 (blue-white), for PEKU/
PESU only. (For MDF pin numbers, see
Chapter 10 – Universal Slot PCB Wiring .)
4. At the modular block, measure the resistance between all wire combinations. The proper
readings are shown in Table 14-3 for digital telephones, DDSSs, DDCBs and Table 14-4 for
electronic telephones and HDSSs.
5. An improper reading indicates an open, crossed or shorted wire. “Power Supply Removal and
Replacement” on Page 1-8 (DK14), or Page 3-19 (DK40i), or Page 5-8 (DK424).
Table 14-2 Station Cable Continuity Check for Electronic Telephone Cables using Voltmeter
From To
Voltage
Pair Wire Color Pair Wire Color
1 T Green
1
1. The green-red, black-yellow and white-blue measurements should be within 10%
of each other.
2 T Black 24
2
2. Nominal voltage—within limits of
±
26.3 ~
±
27.8VDC while under AC power,
polarity depending on voltmeter lead placements.
1 R Red 2 T Black 24
2
1 T Green 2 R Yellow 24
2
1 R Red 2 R Yellow 24
2
1 T Green 1 R Red 0
2 T Black 2 R Yellow 0
3 T White 3 R Blue 0
3 T White 1 R Red 0
3 R Blue 1 R Red 0
3 T White 1 T Green 0
3 R Blue 1 T Green 0
3 T White 2 T Black 0
3 R Blue 2 T Black 0
3 T White 2 R Yellow 0
3 R Blue 2 R Yellow 0