Ohmmeter Test - Toshiba STRATA DK14 Installation And Maintenance Manual

Fault Finding
Station Cable Continuity Check
Table 14-2 Station Cable Continuity Check for Electronic Telephone Cables using Voltmeter
1.
2.

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
4. At the modular block, measure the resistance between all wire combinations. The proper
readings are shown in
electronic telephones and HDSSs.
5. An improper reading indicates an open, crossed or shorted wire.
Replacement" on Page 1-8
14-8
From
Pair Wire Color
1 T Green
1 R Red
1 T Green
1 R Red
1 T Green
2 T Black
3 T White
3 T White
3 R Blue
3 T White
3 R Blue
3 T White
3 R Blue
3 T White
3 R Blue
The green-red, black-yellow and white-blue measurements should be within 10%
of each other.
Nominal voltage—within limits of
polarity depending on voltmeter lead placements.
Table 14-3
(DK14), or
To
Pair Wire
1
2 T
2 T
2 R
2 R
1 R
2 R
3 R
1 R
1 R
1 T
1 T
2 T
2 T
2 R
2 R
26.3 ~ 27.8VDC while under AC power,
± ±
Chapter 10 – Universal Slot PCB
for digital telephones, DDSSs, DDCBs and
Page 3-19 (DK40i), or
Voltage
Color
2
Black 24
2
Black 24
2
Yellow 24
2
Yellow 24
Red 0
Yellow 0
Blue 0
Red 0
Red 0
Green 0
Green 0
Black 0
Black 0
Yellow 0
Yellow 0
Wiring.)
Table 14-4
"Power Supply Removal and
Page 5-8 (DK424).
Strata DK I&M 6/00
for