Toshiba Strata AirLink DK40i, Руководство по установке и обслуживанию

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Fault Finding
Station Cable Continuity Check
Strata DK I&M 6/00
14-7
Fault
F
inding
Station Cable Continuity Check
Voltmeter Test
Use a voltmeter to check cable continuity between the DK40i KSU/DK424 cabinet, digital or
electronic telephone, DSS console, and the attendant console (DK424). Make tests at the modular
block. Refer to
Tables 14-1 and 14-2 .
➤
To perform the voltmeter test
1. Refer to Chapter 10 – Universal Slot PCB Wiring for appropriate MDF wiring diagrams in
Chapters 1 and 3.
2. Disconnect the digital or electronic telephone, DSS console, PDIU-DS, HDCB, or DDCB.
3. Using a DC voltmeter, measure between the wires of the two pairs to verify the readings
shown in Table 14-1 for digital telephone ports. Refer to Table 14-2 for electronic telephone
ports. The reading will be a plus or minus depending on meter lead placement.
4. An improper reading indicates an open, crossed or shorted wire. See “Power Supply Removal
and Replacement” on Page 1-8 , Page 3-19 , or Page 5-11 .
5. For the MDF-to-telephone (digital or electronic) cable, use an ohmmeter to make a more
precise check.
Table 14-1 Station Cable Continuity Check for Digital 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 0
1 R Red 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 T Green 2 R Yellow 24
2
1 R Red 2 R Yellow 0
1 T Green 1 R Red 24
2
2 T Black 2 R Yellow 24
2