Toshiba Strata CT, Инструкция по установке и обслуживанию

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Fault Finding
8-6
Strata CT I&M Manual October 2000
Cable Installation Test
If cable voltmeter and ohmmeter tests are within limits, digital telephones, DDCBs, or DDSS
consoles may not operate.
➤
To perform the cable installation test
1. Cable runs for the above digital devices must be free of cable splits (single or double).
Test for and eliminate all cable splits.
2. Cable bridge taps – Digital telephones will not operate if cable runs contain any type
(short or long) of cable bridge. Test for and eliminate all cable bridges.
3. When installing the station cable, do not run parallel to and within 3 ft. of an AC power
line. AC power lines should cross at right (90
°
) angles only. In particular, avoid running
station wire pairs near devices that generate electrical noise, such as neon or fluorescent
light fixtures.
Table 8-3 Station Cable Continuity Check for Digital Telephone Cables using Ohmmeter
From To
Voltage
Pair Wire Colour Pair Wire Colour
1 T Green
1
2 T Black open
1 R Red 2 T Black open
1 T Green 2 R Yellow open
1 R Red 2 R Yellow open
1 T Green 1 R Red 40 ohms
2
2 T Black 2 R Yellow 40 ohms
2
H
C