Specifications

Maintenance
IMI 66-031
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3. Release the station 10 select key, and note that the BLF
indicators will each turn on in sequence beginning with the
station 10 indicator.
The indicators will then turn off and the
console will become operational.
Data Line Pairing
All stations are even/odd paired on the data lines as shown in Table
3.
Station 10 is paired with station 11, etc.
If erratic light
indications or ring signals occur at a paired station, an open data
pair at either station may be the fault..
A station with an open data
line may work properly on a short loop but fail on a long loop. Test
the station wiring per the checkout procedure given in Chapter 2.
Overload Pairing
All stations are paired as shown in Table 3 for overload current
protection.
If a fault occurs which causes more than 300 ma. of
current to be drawn,
the paired stations are disabled by circuit
r
action.
Disconnect the disabled
time to isolate the faulty one.
stations and reconnect-them one at a
Table
3.
DATA LINE PAIRING
Station Pairing
OVERLOAD PAIRING
lo--11
lo--12
12--13
ll--13
14--15
14--16
16--17
150-17
18--19
18--20
20--21
19--21
22--23 22--24
24--25
23--25
Figure 9 details a failure analysis flow chart to assist a service
technician in isolating a failure in a defective system.
One way to
isolate a failure is to substitute a known good assembly for a
suspected one.
This is the recommended failure isolation method to
use with the system.
Connecting and disconnecting stations to the system does not affect
the stored station auto/speed dial memory data.
This data is stored
in the KSU memory and not at the individual stations.
Replacing the
KSU, however,
causes all stored memory to be lost.
This includes all
memory dialing numbers as well as all COS programming data.
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