TOA Electronics TOAEXES-5OOO User Manual

INTERCOM SYSTEM

TOAEXES-5OOO

INTERCOM SYSTEM

TROUBLE SHOOTING GUIDE

TOA ELECTRIC CO., LTD.

KOBE, JAPAN

8.TROUBLE SHOOTING GUIDE

Repairing of the EXES-5000 system is basically done by replacing defective units with good ones. The system's faults in an installation can be divided into the following categories.

1.Faults in an exchange

2.Faults in a station

3.Cable faults

To make system repairing easier, find which category is

involved, then refer to the chart below for assistance

in fault finding.

All stations do	not operate.	Fault	in specific station
Same symptom in	every station.	only.

Fault in an exchange. Cable fault. Fault in a station.

Power supply	Mis-wiring between exchange
Plug-in unit	and terminal board.
(Common control)	Mis-wiring such as short,
Back wiring on	broken wire,	etc.
frame	Misconnection	in station
	jack.

Key board switch fault. Board assembling fault. Speaker, microphone fault. Microswitch, connecting cable fault.

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START

DIP switch on CPU correctly set ?

Back-up battery on

CPU connected ?

Program switch on

CPU off ?

Power switch on

Proper voltages at each output power terminal? (tabl 1)

No.15 of SCN SELECT on OCU lit brighter than others ?

CLOCK lamp on HCU lit brightly ?

Other lamps on HCU off ?

Station No. lamp on LMU lit corresponding to station connected ?

Clear all No.200 programmings

Dial	at any M-station

EXES-5000 SYSTEM CHECK FLOW CHART

Set DIP	switch
according to Inst.		P54
Plug the	Jack into
Pin A.		P56
Program	switch off

Disconnect DC power connection and check

Replace CPU

Replace HCU

Replace HCU OCU CPU

Check wiring to the station Replace the station LMU

One of LINK BUSY lamps on

Replace Station

HCU lit brightly ?

Turn on LINK SELECT switch(es) on HCU to make

the total number of marked number to be the

Replace

number of LINK BUSY lamp lit. The station dialled correspond to ADDRESS-T lamp.

On dialling	dial tone
heard ?

Call from any station to any station

Calling station and called station correspond to lamps lit on ADDRESS T and R SIG.CORD lamp lit as Fig.2

Calling tone heard ?

Two way conversation OK ?

All other links OK ?

Conversation possible with all station ?

END

Dial	SIG. CORD lamps

on HCU lit as Fig. 1 momentary

In other links, dial tone and lamps OK ?

Replace Station CPUHCU

Replace SGD — Station wiring

In other links ?

Replace CLU or DLU concerned

Program No.200 functions

Table 1:

Fig. 1

Fig. 2

If +24V or +18V is not in the range, check power supply (DS-510). If +12V or +5V is not in the range, replace DC/DC inverter.

Replace HCU; OCU CPU

Replace SGD HCU Station

Replace CLU or DLU

Replace Station CLU or DLU

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8-1. FAULT IN EXCHANGE

Before power supply check, confirm the following three points to eliminate elementary faults:

1.Is voltage selector set correctly?

2.Is AC power supplied?

3.Is power switch ON?

Start checking after disconnecting all wiring connected to DC output of the power supply unit.

SYMPTON	CHECK-ITEM
Exchange does not	All DC output		Over-current flows into one
operate.	voltages are		of plug-in units.
	correct.
	All or one of		Fault in the power supply
	DC output		unit DS-510.
	voltages are
	not correct.
Abnormal voltage	Right	range:	Replace AC and DC fuses.
of +24V terminal.	+24 ~ +30V		Incorrect setting of the
			voltage selector.
			Faulty power transformer.
Abnormal voltage	Right	range:
of +18V.
Abnormal voltage	Right	range:	DC/DC inverter (MIV-02) is
of +5V or +12V.			defective.
Battery is not	Check	the cur-	Replace PCB of charging
charged.	rent	flowing	circuitry.
	into	the bat-
	tery.
	Right	range:

AC & DC operation		Check all DC
lamps	are OFF.	voltage.
Buzzer	does not

operate.

Note: Only when DC power supply (Battery) is employed.

Blown AC and/or	All DC output
DC fuse.	voltages are
	correct.
	heck	all sta-
	tions	involv-
	ed in All-Call
	paging.

Replace PCB of charging circuitry.

Over-current flows into one of plug-in units.

(Especially on +18V)

MIV-02 is defective. Replacefuseaccordingto the following.

Number of stations	Fuse
0 ~ 30	DC 5A

31 ~ 64	DC	7A
65~	DC	10A

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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.

Power ON	OFF
	Normal
Lamp ON	Abnormal
	(Short)
Lamp ON
(Brighter	than normal)
	Lamp goes off gradually

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1. One of transmitting lines (T-Line) is disconnected.

Station

			EXCHANGE
Symptom 1-1	A	can make dialing.
1-2	A	can hear		B .
1-3	B	can not hear			A .
1-4	Noise		is heard at			B .
1-5	Noise		increases		at	B when Press-To-Talk bar is
	pressed at			A .
LMU Lamps		Normal

2.One of receiving lines (R-Line) is disconnected.

			EXCHANGE
Sympton: 2-1	A can	make dialing without dialing tone.
2-2	When	B	dials A , busy tone	or dial tone will be
	heard	at	B immediately after	the calling tone.
LMULamps -----	Normal

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3.T-Line and R-Line are shorted or mixed up.

Shorted or mixed up

	EXCHANGE
Symptom 3-1	A can not dial.
3-2	Conversation is impossible between stations.
3-3	When B dials	A , noise will be heard at B
	immediately after the calling tone.
LMU Lamps	Brighter	than normal.

4.T-Line and R-Line are connected conversely.

Sympton: 4-1	A can not make dialing.
4-2	Conversation is impossible between stations.
4-3	When B dials	A , noise will be heard at B .
LMU Lamps	Brighter	than normal.

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8-3. FAULT IN SPECIFIC STATION ONLY

Find the cause according to the following table if the fault

lies with a specific station only, not with all stations.

	CHECK-ITEM	CAUSE
Dialing can not	LMU Lamp is	Disconnection of both T & R-Lines.
be made at privacy	off.	Guard resistor 330 on LMU is
off mode.		burned out due to T & R-Lines
		short.

Specific key does not operate.

Calling tone can not be heard.

Dialing tone can not be heard on dialing.

Sound from the other party can not be heard.

Sound is not transmitted to the other party.

On dialing, noise is heard by the called party.

Specific Lamp			T & R-Lines are shorted.
on	LMU is
brighter		than
normal.
LMU Lamp		is	Fault in the station.
on in normal.			(Replace PCB board.)
Replace the			Fault in key board switch or
station		and	matrix circuitry.
make sure that			Fault in the dial generator.
the station			(Replace PCB board.)
is not faulty.
Same sympton			Short or open in R-Line.
remains even			Fault in the demodulation cir-
if the station			cuitry on LMU.
is replaced.			(Check LM-380, MT-547.)
Becomes normal			Disconnection of R-Line or im-
if	the station		proper connection of the station
is replaced.			connector.
			Fault in MT-547 on LMU.
			Station fault.
Same sympton			Short or open in T-Line.
remains		even	Fault in the modulation cir-
the station			cuitry on LMU.
is replaced.
Becomes normal			Fault in MIC circuitry of the
if	the station		station. (Replace MIC or PCB)
is replaced.
Same sympton			One of T-Lines is disconnected.
remains		even
the	station is
replaced.
Becomes normal			Fault in MIC element.
if	the station		Fault in T-Line of the station.
is	replaced.		Low frequency oscillation of
			MIC AMP. (Faulty bypass capaci-
			tor)

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Sound	of	the	other	Same symptom		Adjust the volume control of
party	is	broken		remains even		station speaker if the room
during call.				the	station	produces reverberation.
				is	replaced.	(Lower the volume.)
						Increase the gain of MIC AMP.
						Replace PCB after checking if
						MIC unit is not touching its
						case.
Immediately			after	Same symptom		One of R-Lines is disconnected.
the calling			tone,	remains even		Fault in photo coupler PC-504
the line switches				the	station	on LMU.
to cancel, busy,				is	replaced.	Fault in MT-547 on LMU or in
dial tone, etc.						the station.
				Becomes normal		One of the R-Lines is discon-
				if	the station	nected or the station connector
				is	replaced.	is not connected properly.

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8-4. SPEECH AND FUNCTION TEST

1.Speech Test

After completing the wiring check and the power supply

and exchange test according to the system flow chart,

the speech test for each station can then take place.

IMPORTANT NOTE

Before testing, all programming (Secretary transfer,

Master/Substation, Executive Priority Function) must

be cleared from station No.200 by turning on the PRO-

GRAM switch of the CPU, or the speech test can not

proceed correctly.

Call every station one by one from any master station

and examine the speech quality and sound volume.

The sound volume can be adjusted by the volume on the

rear of the station. (Fully clockwise for maximum)

A call to a station in the room produces reverbera-

tion and may present broken sound. Turn down the

volume of the station speaker until the sound becomes

normal.

Each station must be located properly where no feed-

back will occur between station and external speakers.

The gain adjustment of the paging amplifier is also

important in order to avoid troublesome feedback.

The Press-To-Talk bar on the station keyboard must be

used for the speech test when stations are installed

in high noise areas (more than 60dB noise).

Speech quality (broken sound, natural conversation,

tone quality, etc.) must be tested with each line in

the CLU or DLU employed in the system.

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2.Function Test

Check all employed functions with a few stations near the exchange.

Check "User Programmable Functions" at stations involved after the programming from station 200.

Secretary Transfer: Is transfer made correctly

with the privacy switch on

	at the executive			station.
Master/Substation	: Touch dial		at	substation
	can call its master station.
Executive Priority: Is this		function operated at
	stations	involved.
Use all number keys	including		and	, Press-

To-Talk bar, Vol. L/H and privacy switch to test

all functions.

EXAMPLE: Both calling and conversation tests with

station number 200 through 209.

Change the position of Vol. L/H and make

sure that the switch works.

Turn the privacy switch ON. Is privacy

tone heard from the station when some-

one calls?

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MEMO

MEMO

TOA ELECTRIC CO., LTD.

KOBE, JAPAN

Printed in Japan

EX5(7)-01R(79-2)