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TOA Electronics TOAEXES-5OOO User Manual

Page 5

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8-2. HOW

TO

FIND

SHORT

BETWEEN T-LINE AND R-LINE

If the shorted condition between T-line and R-line is not

corrected for a long time, it may burn out the guard re-

sistor (330 , 1/2W) on the LMU board. Therefore,

find

the shorted line according to the following procedure:

1. Turn

off

the

privacy switch on all stations in the

system.

2. Turn on the power switch of the system for several

seconds, then, turn it off.

3. Watch the lamps on the LMU panels. The lamps on

normal lines will go off after approximately 0.5

second. The

lamps on the shorted lines will stay

on more than 0.5 second.

Normal

Abnormal

(Short)

Lamp goes off gradually

Power ON

Lamp ON

Lamp ON

(Brighter than normal)

OFF

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