Marantz Icemaker User manual

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Integrated Amplier
PM7005 /N1B, N1SG, U1B, K1B,
FN
PM7005
S1027-V03DM/SG1506
Copyright 2015 D&M Holdings Inc. All rights reserved.
WARNING: Violators will be prosecuted to the maximum extent possible.
Ver. 3
•Some illustrations using in this service manual are slightly different from the actual set.
•Please use this service manual with referring to the operating instructions without fail.
•For purposes of improvement, specications and design are subject to change without notice.
Please refer to the
MODIFICATION NOTICE.
Service
Manual

Contents
ABOUT THIS MANUAL.............................................................3
What you can do with this manual ............................................3
Using Adobe Reader (Windows version) ..................................4
SAFETY PRECAUTIONS ..........................................................6
NOTE FOR SCHEMATIC DIAGRAM.........................................7
NOTE FOR PARTS LIST ...........................................................7
TECHNICAL SPECIFICATIONS................................................9
DIMENSION ...............................................................................9
PRECAUTIONS DURING SERVICE .......................................10
Initializing This Unit .................................................................10
DISASSEMBLY........................................................................11
1. FRONT PANEL ASSY ........................................................13
2. HEAT SINK ASSY ..............................................................14
3. DIGITAL PCB .....................................................................15
4. PHONO HDAM PCB ..........................................................16
5. MAIN PCB.........................................................................16
6. STANDBY PCB ..................................................................17
7. TRANS POWER ................................................................17
SPECIAL MODE ......................................................................18
1. Version Display ..................................................................18
2. How to change the Auto Standby Mode.............................18
3. PROTECTION MODE........................................................19
PROCEDURE AFTER REPLACING THE
MICROPROCESSOR, ETC. ...................................................22
FIRMWARE UPDATE PROCEDURE .....................................22
ADJUSTMENT.........................................................................30
TROUBLE SHOOTING............................................................32
1. The power can not be turned on. ......................................32
2. The power can not be turned on. ......................................32
3. STANDBY LED FLASHES WHILE USING UNIT .............33
4. The power turned on, but a sound does not output
normally..................................................................................33
5. 8U-310151 (DIGITAL PCB) DIR BLOCK............................34
6. 8U-310151 (DIGITAL PCB) USB-B BLOCK ......................35
MEASURING METHOD AND WAVEFORMS .........................36
LEVEL DIAGRAM....................................................................40
BLOCK DIAGRAM...................................................................41
POWER DIAGRAM..................................................................42
WIRING DIAGRAM..................................................................43
PRINTED Circuit BOARDS.....................................................44
SCHEMATIC DIAGRAMS (1/10 ) ............................................48
MAIN .......................................................................................48
POWER BUFFER ...................................................................49
PHONO&HDAM ......................................................................50
FRONT....................................................................................51
SELECTOR STANDBY ...........................................................52
DIGITAL 1................................................................................53
DIGITAL 2................................................................................54
DIGITAL 3................................................................................55
DIGITAL 4................................................................................56
DIGITAL 5................................................................................57
EXPLODED VIEW ...................................................................58
PACKING VIEW .......................................................................59
SEMICONDUCTORS ...............................................................60
1. IC's .....................................................................................60
2

Jump to the target of a schematic
diagram connector
Click the Ref. No. of the target connector in the red
box around a schematic diagram connector.
•The screen jumps to the target connector.
•Pagemagnicationstaysthesameasbeforethe
jump.
CP401
CP106
v
ABOUT THIS MANUAL
Read the following information before using the service manual.
What you can do with this manual
Search for a Ref. No. (phrase)
(Ctrl+Shift+F)
You can use the search function in Acrobat Reader
to search for a Ref. No. in schematic diagrams, block
diagrams, and parts lists.
1.Press Ctrl+Shift+Fonthekeyboard.
• The Search window appears.
2.EntertheRef.No.youwanttosearchforinthe
Search window, and then click the Search button.
•A list of search results appears.
3.Click an item on the list.
• The screen jumps to the page for that item, and the
searchphraseisdisplayed.
Ctrl
Shift
F
3

Using Adobe Reader (Windows version)
• Properties
Click this button and check that the printer is set to a
suitable paper size.
• Page to print
Select the following checkbox.
"More Options" : "Current View"
• Page Sizing & Handling
Select the following checkbox.
"Size" / "Size Options" : "Fit"
Add notes to this data (Sign)
TheSignfunctionletsyouaddnotestothedatain
this manual.
Savetheleonceyouhavenishedaddingnotes.
[Example using Adobe Reader X]
On the "View" menu, click "Sign".
• The Sign pane appears.
[Example using Adobe Reader 9]
On the "Document" menu, click "Sign".
Magnify schematic / printed wiring
board diagrams - 1
(Ctrl+Space, mouse operation)
Press Ctrl+Spaceonthekeyboardanddragthe
mousetoselecttheareayouwanttoview.
• Theselectedareaismagnied.
• Whenyouwanttomovetheareashown,hold
down Space and drag the mouse.
• Whenyouwanttoshowafullpageview,press
Ctrl+0onthekeyboard.
Ctrl Space
0
Print a magnied part of the manual
ThePropertiesdialogboxandfunctionswillvarydependingonyourprinter.
1. Dragthemousetomagnifythepartyouwanttoprint.
2. On the "File" menu, click "Print".
3. CongurethefollowingsettingsinthePrintdialogbox.
4. Click the Print button to start printing.
4

Magnify schematic / printed wiring
board diagrams - 2
(Pan & Zoom function)
ThePan&Zoomfunctionletsyouseewhichpartof
amagnieddiagramisbeingshowninaseparate
window.
[Example using Adobe Reader X]
On the "View" menu, point to "Zoom", and then click
"Pan & Zoom".
• The Pan & Zoom window appears on the screen.
[Example using Adobe Reader 9]
On the "Tools" menu, point to "Select & Zoom", and
then click "Pan & Zoom Window".
Magnify schematic / printed wiring
board diagrams - 3
(Loupe Tool function)
TheLoupeToolfunctionletsyoumagnifyaspecic
part of a diagram in a separate window.
[Example using Adobe Reader X]
On the "View" menu, point to "Zoom", and then click
"Loupe Tool".
• The Loupe Tool window appears on the screen.
[Example using Adobe Reader 9]
On the "Tools" menu, point to "Select & Zoom", and
then click "Loupe Tool Window".
5

SAFETY PRECAUTIONS
The following items should be checked for continued protection of the customer and the service technician.
leakage current check
Beforereturningthesettothecustomer,besuretocarryouteither(1)aleakagecurrentcheckor(2)alinetochassis
resistance check. If the leakage current exceeds 0.5 milliamps, or if the resistance from chassis to either side of the
power cord is less than 460 kohms, the set is defective.
Be sure to test for leakage current with the AC plug in both polarities, in addition, when the set's power is in each state
(on,offandstandbymode),ifapplicable.
CAUTION Please heed the following cautions and instructions during servicing and
inspection.
◎Heed the cautions!
Cautions which are delicate in particular for servicing
are labeled on the cabinets, the parts and the chassis,
etc. Be sure to heed these cautions and the cautions
described in the handling instructions.
◎Cautions concerning electric shock!
(1) AnACvoltageisimpressedonthisset,soifyou
touch internal metal parts when the set is energized,
youmaygetanelectricshock.Avoidgettingan
electricshock,byusinganisolatingtransformer
and wearing gloves when servicing while the set is
energized,orbyunpluggingthepowercordwhen
replacing parts, for example.
(2) Therearehighvoltagepartsinside.Handlewith
extra care when the set is energized.
◎Caution concerning disassembly and
assembly!
Through great care is taken when parts were
manufacturedfromsheetmetal,theremaybeburrson
theedgesofparts.Theburrscouldcauseinjuryifngers
are moved across them in some rare cases. Wear gloves
toprotectyourhands.
◎Use only designated parts!
Theset'spartshavespecicsafetyproperties(re
resistance,voltageresistance,etc.).Besuretouseparts
which have the same properties for replacement. The
burrs have the same properties. In particular, for the
importantsafetypartsthatareindicatedbythezmark
on schematic diagrams and parts lists, be sure to use
the designated parts.
◎Be sure to mount parts and arrange the wires
as they were originally placed!
Forsafetyseasons,somepartsusetapes,tubesorother
insulatingmaterials,andsomepartsaremountedaway
from the surface of printed circuit boards. Care is also
takenwiththepositionsofthewiresbyarrangingthem
andusingclampstokeepthemawayfromheatingand
highvoltageparts,sobesuretoseteverythingbackas
itwasoriginallyplaced.
◎Make a safety check after servicing!
Check that all screws, parts and wires removed or
disconnected when servicing have been put back in their
original positions, check that no serviced parts have
deteriorate the area around. Then make an insulation
check on the external metal connectors and between
the blades of the power plug, and otherwise check that
safetyisensured.
(Insulationcheckprocedure)
Unplug the power cord from the power outlet, disconnect
the antenna, plugs, etc., and on the power. Using a 500V
insulation resistance tester, check that the insulation
resistancevaluebetweentheinplugandtheexternally
exposedmetalparts(antennaterminal,headphones
terminal,inputterminal,etc.)is1MΩorgreater.Ifitis
less, the set must be inspected and repaired.
Manyoftheelectricandthestructuralpartsusedinthe
sethavespecialsafetyproperties.Inmostcasesthese
propertiesaredifculttodistinguishbysight,andtheuse
ofreplacementpartswithhigherratings(ratedpower
andwithstandvoltage)doesnotnecessarilyguarantee
thatsafetyperformancewillbepreserved.Partswith
safetypropertiesareindicatedasshownbelowonthe
wiring diagrams and the parts list in this service manual.
Be sure to replace them with the parts which have the
designated part number.
(1) Schematicdiagrams.......Indicatedbythez mark.
(2) Partslists.......Indicatedbythezmark.
The use of parts other than the
designated parts could cause electric
shocks,resorotherdangerous
situations.
CAUTION Concerning important
safety parts
6

NOTE FOR PARTS LIST
1.Partsindicatedby"nsp" on this table cannot be supplied.
2.Whenorderingapart,makeacleardistinctionbetween"1"and"I"(i)toavoidmis-supplying.
3.Apartorderedwithoutspecifyingitspartnumbercannotbesupplied.
4.Partindicatedby" ★" mark is not illustrated in the exploded view.
WARNING:Partsindicatedbythezmarkhavecriticalcharacteristics.UseONLYreplacementpartsrecommendedbythemanufacturer.
NOTE FOR SCHEMATIC DIAGRAM
WARNING:
Partsindicatedbythezmarkhavecriticalcharacteristics.UseONLYreplacementpartsrecommendedbythemanufacturer.
CAUTION:
Beforereturningthesettothecustomer,besuretocarryouteither(1)aleakagecurrentcheckor(2)alinetochassisresistancecheck.If
the leakage current exceeds 0.5 milliamps, or if the resistance from chassis to either side of the power cord is less than 460 kohms, the set
is defective.
WARNING:
DONOTreturnthesettothecustomerunlesstheproblemisidentiedandremedied.
NOTICE:
ALLRESISTANCEVALUESINOHM.k=1,000OHM/M=1,000,000OHM
ALLCAPACITANCEVALUESAREEXPRESSEDINMICROFARAD,UNLESSOTHERWISEINDICATED.PINDICATESMICRO-MICRO
FARAD.EACHVOLTAGEANDCURRENTAREMEASUREDATNOSIGNALINPUTCONDITION.CIRCUITANDPARTSARESUBJECT
TOCHANGEWITHOUTPRIORNOTICE.
INSTRUCTIONS FOR HANDLING SEMI-CONDUCTORS AND OPTICAL UNIT
Electrostaticbreakdownofthesemi-conductorsoropticalpickupmayoccurduetoapotentialdifferencecausedby
electrostatic charge during unpacking or repair work.
1. GroundforHumanBody
Besuretowearagroundingband(1MΩ)thatisproperlygroundedtoremoveanystaticelectricitythatmaybe
chargedonthebody.
2. GroundforWorkbench
Besuretoplaceaconductivesheetorcopperplatewithpropergrounding(1MΩ)ontheworkbenchorothersurface,
wherethesemi-conductorsaretobeplaced.Becausethestaticelectricitychargeonclothingwillnotescapethrough
thebodygroundingband,becarefultoavoidcontactingsemi-conductorswithyourclothing
<Incorrect>
CBA
Grounding Band
Conductive Sheet or
Copper Plate
1MΩ
1MΩ
<Correct>
CBA
7

Personal notes:
8

Unit : mm
Weight: 10.0kg
22559 45
14 111
125
440
340
56
5050
329 379
2
381
• RMS Power output (20 Hz -20 kHz simultaneous drive of bothchannels) : 60 W x 2 (8 Ω/ohms load)
80 W x 2 (4 Ω/ohms load)
• Total harmonic distortion
(20 Hz-20 kHz simultaneous drive of bothchannels, 8 Ω/ohms load) :
0.02 %
• Output band width (8 Ω/ohms load, 0.06 %) : 5 Hz - 60 kHz
• Frequency response (CD, 1 W, 8 Ω/ohms load) : 5 Hz - 100 kHz ± 3 dB
• Dumping factor (8 Ω/ohms load, 40 Hz-20 kHz) : 100
• Input sensitivity/Input impedance
PHONO (MM) : 2.0 mV/47 k Ω/kohms
CD, TUNER, NETWORK, RECORDER : 200 mV/20 k Ω/kohms
• Maximum allowable PHONO input level (1 kHz) MM : 100 mV
• RIAA deviation (20 Hz -20 kHz) : ±0.5 dB
• S/N (IHF-A, 8 Ω/ohms load)
PHONO (MM) : 85 dB (5 mV input, 1 W output)
CD, TUNER, NETWORK, RECORDER : 104 dB (2 V input, Rated output)
• Tone Control
BASS (50 Hz) : ±10 dB
TREBLE (15 kHz) : ±10 dB
• Power requirement : (F)AC100V、50/60Hz
(N)AC230V, 50/60Hz
(U)AC120V, 60Hz
(K)AC220V、50Hz
• Power consumption : 170W
• Power consumption in standby mode : 0.2 W
• Digital input signal format
Format: Digital audio interface (Linear PCM)
Coaxial input: 0.5 Vp-p / 75 Ω/ohms
Optical input: More than – 27 dBm
Optical wavelength: 660 nm
TECHNICAL SPECIFICATIONS
DIMENSION
9

Initializing This Unit
Initialize this unit if you have replaced the microcomputer, one of the parts around the microcomputer.
1. Press the "POWER" button to turn off the power.
2. Hold down buttons "SOURCE DIRECT" and press the power button to turn on the power.
3. Check the set entered the service mode.( See 18 page SPECIAL MODE)
Cautions:
If replace the DIGITAL PCB of this unit for F, U and K Region, you remove the R0166 (1k ohm).
This resistance is set for the destination settings, and uses the default value of Auto Standby mode.
N Region : Tuning Auto Standby mode OFF by default. F/U/K Region：Tuning Auto Standby mode OFF by default.
Note : 18 page 2. How to change the Auto Standby Mode
Service Jigs
The following jigs are used when updating the rmware
(RS232C → connector conversion PCB in this product + 7P cable kit).
Order the jigs from your dealer if necessary
00DSPK-581 : WRITING KIT. 1
606050028012P : 7P FFC (Straight) 1
See : 22 page FIRMWARE UPDATE PROCEDURE
SPEAKERSPOWER SOURCE DIRECT
Power indicator
PRECAUTIONS DURING SERVICE
10

DISASSEMBLY
• Remove each part in the order of the arrows below.
• Reassemble removed parts in the reverse order.
• Read "Precautions During Work" before reassembling removed parts.
• If wire bundles are removed or moved during adjustment or part replacement, reshape the wires after completing the
work. Failure to shape the wires correctly may cause problems such as noise.
FRONT PANEL ASSY
See "DISASSEMBLY
1. FRONT PANEL ASSY
and "EXPLODED VIEW"
HEADPHONE PCB
(Ref. No. of EXPLODED VIEW : P8)
STANDBY LED PCB
(Ref. No. of EXPLODED VIEW : P5)
FRONT PCB
(Ref. No. of EXPLODED VIEW : P7)
SELECTER PCB
(Ref. No. of EXPLODED VIEW : P6)
POWER SW PCB
(Ref. No. of EXPLODED VIEW : P10)
TOP COVER
TRANS POWER
See "DISASSEMBLY
7. TRANS POWER
and "EXPLODED VIEW"
MAIN TRANS
(Ref. No. of EXPLODED VIEW : T0001)
HEAT SINK ASSY
See "DISASSEMBLY
2. HEAT SINK ASSY
and "EXPLODED VIEW"
POWER BUFFER PCB
(Ref. No. of EXPLODED VIEW : P2)
CLAMP PCB
(Ref. No. of EXPLODED VIEW : P9)
DIGITAL PCB
See "DISASSEMBLY
3. DIGITAL PCB
and "EXPLODED VIEW"
DIGITAL PCB
(Ref. No. of EXPLODED VIEW : P4)
PHONO HDAM PCB
See "DISASSEMBLY
4. PHONO HDAM PCB
and "EXPLODED VIEW"
PHONO HDAM PCB
(Ref. No. of EXPLODED VIEW : P12)
MAIN PCB
See "DISASSEMBLY
5. MAIN PCB
and "EXPLODED VIEW"
MAIN PCB
(Ref. No. of EXPLODED VIEW :P1)
VOLUME PCB
(Ref. No. of EXPLODED VIEW : P14)
STANDBY PCB
See "DISASSEMBLY
6. STANDBY PCB
and "EXPLODED VIEW"
STANDBY PCB
(Ref. No. of EXPLODED VIEW : P11)
11

Explanatory Photos for“ DISASSEMBLY”
• The angles from which the photos are taken are shown by “Photo angle: A, B, C, D“ .
• See the diagram below about the shooting direction of each photograph.
• Photographs with no shooting direction indicated were taken from the top of the set.
• The photograph is PM7005F.
The viewpoint of each photograph
(Shooting direction)
Front side
Shooting
direction: D Shooting
direction: C
↑Shooting direction: A↑
↓Shooting direction: B↓
12

1. FRONT PANEL ASSY
Proceeding : TOP COVER →FRONT PANEL ASSY
(1) Remove the nut, the washer and screws.
(2) Cut the wire clampers and remove the connector wires. Remove the screws.
View from the bottom
TOP
bottom
NUT and WASHER
N8502
N2802
N2801
N5901
N102
N9901
CUT
13

2. HEAT SINK ASSY
Proceeding : TOP COVER →HEAT SINK ASSY
(1) Cut the wire clamper and remove the screws. Remove the connector wires.
N7501
N8001
N7002
N7001
N9002 CUT
14

3. DIGITAL PCB
Proceeding : TOP COVER →DIGITAL PCB
(1) Remove the connector wires. Remove the screws.
(2) Remove the screws.
N101
N701
N301
N105
N104 N102
CUT
15

4. PHONO HDAM PCB
Proceeding : TOP COVER →DIGITAL PCB →PHONO HDAM PCB
(1) Remove the screws. Remove the connector wires.
5. MAIN PCB
Proceeding : TOP COVER →DIGITAL PCB →PHONO HDAM PCB →HEAT SINK ASSY →MAIN PCB
(1) Remove the screws.
N4002
N4001
PCB HOLDER
16

6. STANDBY PCB
Proceeding : TOP COVER →STANDBY PCB
(1) Remove the connector wires. Remove the screws.
7. TRANS POWER
Proceeding : TOP COVER →TRANS POWER
(1) Cut the wire clamper and remove the connector wires. Remove the screws.
N8501
N8507
N8503
N8505
N8502
STYLE PIN
PCB HOLDER
N8504
N8001
N8504
N8301
N8505
CUT
STYLE PIN
17

1. Version Display
Microprocessor (U101) / USB DAC (U401) version check
(1) Connect the mains cord into the unit.
(2) Press the POWER button with pressing the SOURCE DIRECT button on the Unit.
(3) The rmware version is displayed on the front LED. (Display time is only for 3 seconds.)
The rmware version is displayed in the lighting position of LED.
Ex. :
Light up USB-DAC- [1 ], Version : 1
Light up USB-DAC- [1 ] and COAXIAL [4 ], Version : 5
Light up USB-DAC- [1 ] and RECORDER [8 ], Version : 9
(4) The USB-DAC (DSP) version is displayed on the front LED. (Display time is only for 3 seconds.)
Lighting position is same as rmware version.
(5) Each LED light up then all LED light up.
(6) Turn off the power to quit Service Mode. (The unit to the default status.)
2. How to change the Auto Standby Mode
Turning Auto Standby mode off.
Press and hold SOURCE DIRECT for more than 5 seconds to turn the Auto Standby mode off.
The power indicator ashes once.
Turning Auto Standby mode on.
Press and hold SOURCE DIRECT for more than 5 seconds to turn the Auto Standby mode on.
The power indicator ashes three times.
N Region : Tuning Auto Standby mode OFF by default. F/U/K Region：Tuning Auto Standby mode OFF by default.
124Version: 8
SPECIAL MODE
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3. PROTECTION MODE
Explanation of microprocessor (U101) [PROT_1 (pin26), PROT_2 (pin24), VOLTAGE_PROT (pin25)].
[A] The PROT_1(pin26) is the port to detect the following abnormalities of the Power AMP
1. Detection of an abnormality in the DC offset voltage from the Speaker Output terminal.
If the voltage from the Speaker Output terminal exceeds approximately 1.2V (DC), Q9507 or Q9508 will turn on and
the signal from the PROT_1 terminal will change to "Lo" from "Hi".
2. Detection of an abnormal current from the power transistors (Q7011, Q7013, Q7012, Q7014).
If an electric current of over 7A ows in Q7011 or Q7013, Q9503, Q9505 and Q9509 turn on, and the signal from the
PROT_1 terminal will change to "Lo" from "Hi".
If an electric current of over 7A ows in Q7012 or Q7014, Q9504, Q9506 and Q9509 turn on, and the signal from the
PROT_1 terminal will change to "Lo" from "Hi".
3. Detection of an abnormal temperature of the Heat Sink.
If the temperature of the Heat Sink exceeds approximately +110 degrees C, the posistor (Z9501 or Z9502) will turn on
Q9501 or Q9502 and the signal from the PROT_1 terminal will change to "Lo" from "Hi".
If any of the above three abnormalities is detected, the signal from the PROT_1 terminal will change to "Lo" from "Hi",
and the protection circuit will be activated, the signal from the SPK_OUT (pin19) changing to "Hi" from "Lo" and the
speaker relays S7501 and S7503 immediately turned off.
What this protection operation results in after this depends on how long the signal from the PROT_1 has to remain "Lo".
• If the PROT_1 (pin26) recovers to "Hi" within as short a period of time as one second or less.
The MUTE indicator starts ickering, thereby indicates that the protection circuit has come into operation and
automatically turns down the volume. The protection circuit is deactivated after approximately 15 seconds, so that
readjusting the volume will allow normal use of the unit again. This protection operation is intended for the situation
wherein the user has misused the unit temporarily and automatically resets the unit while the amp circuit is functioning
properly.
• If the PROT_1 (pin26) remains "Lo" for more than one second.
The amp will be powered off by the P_ON (pin78) changing to "Lo" from "Hi" and and Power relay S8501 turned off
Then, the STANDBY indicator ickers, thereby indicating that an error has occurred. This protection operation
is intended for a failure in the amp circuit and immediately turns the power off to avoid the risk of any damage.
Depending on how the user is handling the unit, this operation may be performed no matter if the amp is functioning
properly.
To check if the amp is in order, switch off the unit and switch it on again one minute later. This action will deactivate
the protection operation. If the PROT_1 (pin26) remains "Lo", which constitutes an abnormality, the unit shuts down
approximately 3 seconds later and the STANDBY indicator starts ickering.
If the protection operation will not be deactivated after the power is turned on again, the amp circuit may be broken.
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[B] The PROT_2 (pin24) is the port to detect abnormalities of the power supply circuit.
1. Detection of an abnormality in the power amp power supply circuit.
This port monitors the midpoint voltage of the power amp power supply between +B and -B. If the voltage at the
connection point of R8001 and R8002 exceeds DC ±1.2V, Q9003 or Q9004 will turn on to change the signal from the
PROT_2 (pin24) to "Lo" from "Hi".
2. Detection of an abnormality in the preamp power supply circuit.
Q9001 and Q9002 monitors the midpoint voltage between +28V and -28V. If the voltage at the connection point of
R8109 and R8110 exceeds DC ±0.9V, Q9001 or Q9002 will turn on to change the signal from the PROT_2 (pin24) to
"Lo" from "Hi".
3. Detection of an abnormality in the function relay power supply circuit.
If the +24VL of the relay power supply receives an electric current of over 80mA, Q8015 and Q9001 will turn on to
change the signal from the PROT_2 (pin24) to "Lo" from "Hi".
If any of the above three abnormalities is detected, the signal from the P_ON (pin78) terminal will be changed to "Lo" from
"Hi", the power relay S8051 will be turned off and the unit will be shut down. Then, the STANDBY indicator ickers and
indicates that an abnormality has occurred.
This protection operation is intended for a breakdown of the AMP circuit or the power supply circuit and immediately shuts
off the power in order to avoid the risk of damage.
To check if the amp circuit or the power supply circuit is broken, switch off the power and then switch it on again one
minute later. This action will deactivate the protection operation.
If the RPOT_2 (pin24) remains "Lo" after the power is switched on again, the unit will be shut down again three seconds
later with the STANDBY indicator ickering.
If the unit is powered on again and yet cannot get the protection operation deactivated, the amp circuit or the power supply
circuit may be broken.
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