Bosch CCS800 User manual

CCS800
Service manual
en Discussion system

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Important Safeguards
Note
Read the ‘Important Safety Instruction’ manual 9922 141 7014x
(instructions enclosed with the LBB 3310 delivery)
•Proper service and repair is important for safe and reliable operation of all Bosch Security Systems equipment.
•Some service operations require the use of tools specially designed for the purpose. These special tools should be
used when recommended.
•To minimize risk of personal injury and damage to the product only trained service personnel with awareness of
hazards of electronically equipment must be allowed to service this product.
•Under no circumstances should the original design be modified or altered without written permission from Bosch
Security Systems. Bosch assumes no liability arising out of any unauthorized modification of design.
Warning
Use of substitute replacement parts, which do not have the same specified characteristics, may create
shock, fire or other hazards. To maintain the Bosch quality the use of recommended Bosch Security
Systems spare parts are suggested.
Note
An ESD protection method should be applied before proceed any Mechanical/ Electrical Instructions.
Note
This material shall be scrapped according to local environment laws & procedures.

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Table of contents
Important Safeguards .....................................................................................................................................................1
1 General information............................................................................................................................................5
1.1 Document history...............................................................................................................................5
1.2 About this manual ..............................................................................................................................5
1.3 Related documentation......................................................................................................................5
1.4 Alerts....................................................................................................................................................5
1.5 Policy & Procedures...........................................................................................................................5
1.5.1 Repair Policy..........................................................................................................................5
1.5.2 Warrantee conditions............................................................................................................5
1.5.3 Service period........................................................................................................................6
1.5.4 Type number survey.............................................................................................................6
1.6 Example RMA request form.............................................................................................................7
2 Introduction .........................................................................................................................................................8
2.1 LBB 3310/00 Control and Power Supply Unit (CPSU) .................................................................8
2.1.1 Block diagram CPSU ............................................................................................................8
2.2 LBB 3310/10 Control and Power Supply Unit with AFS ..............................................................9
2.2.1 Block diagram CPSU with AFS ...........................................................................................9
2.2.2 Audio level diagram CPSU ............................................................................................... 10
2.3 AFS module LBB 3310/10)............................................................................................................ 11
2.3.1 Board function .................................................................................................................... 11
2.3.2 Block diagram AFS board ................................................................................................. 11
2.4 LBB 3330/00 Delegate Unit........................................................................................................... 12
2.4.1 LBB 3330/50 Delegate Unit with Long Microphone Stem............................................ 12
2.4.2 Block diagram delegate unit.............................................................................................. 12
2.5 LBB 3331/00 Chairman Unit......................................................................................................... 13
2.5.1 LBB 3331/50 Chairman Unit with long Microphone stem ........................................... 13
2.5.2 Block diagram chairman unit............................................................................................ 13
2.6 Audio level diagram delegate and chairman units....................................................................... 14
3 Controls and indicators.................................................................................................................................... 15
3.1 Control and Power Supply Unit (CPSU) ...................................................................................... 15
3.2 Delegate and chairman units.......................................................................................................... 16
4 Technical data................................................................................................................................................... 17
4.1 Power supply.................................................................................................................................... 17
4.1.1 Additional technical specification for test environment:................................................ 17
5 Microphone stem adjustment.......................................................................................................................... 18
6 Maintenance and repair................................................................................................................................... 20
6.1.1 Preventive maintenance..................................................................................................... 20
6.1.2 Corrective maintenance..................................................................................................... 20
6.2 Workshop repair.............................................................................................................................. 20
6.2.1 Electrical repair................................................................................................................... 20
6.2.2 Mechanical repair............................................................................................................... 20
6.2.3 Microphone repair ............................................................................................................. 20
7 Diagnostics and Fault finding.......................................................................................................................... 21
7.1 Functional tests with a minimized system..................................................................................... 21
7.1.1 Testing the Light-ring......................................................................................................... 21
7.1.2 Testing the OPEN 1 mode ................................................................................................ 21
7.1.3 Testing The AUTO 1 mode.............................................................................................. 21
7.1.4 Testing the OVERRIDE mode......................................................................................... 21
7.1.5 Testing the CHAIRMAN ONLY mode .......................................................................... 21
7.2 Brief description of the various modes of the chairman and delegate unit ............................... 21
7.2.1 CTRL-L1............................................................................................................................. 22
7.2.2 CTRL-L2............................................................................................................................. 22
7.3 Measuring Instructions for the CPSU ........................................................................................... 22
7.3.1 Settings before you start measuring.................................................................................. 23
7.3.2 Internal Supply Voltages ................................................................................................... 23

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7.3.3 Phantom supply of the external symmetrical microphone input .................................. 23
7.3.4 Supply current measurement. ........................................................................................... 23
7.3.5 Audio contribution to loudspeaker measurement........................................................... 24
7.3.6 Audio contribution to audio distribution measurement ................................................. 25
7.3.7 External microphone input to line out measurement..................................................... 26
7.3.8 Telephone-out, Line-out and Insertion-out measurement.............................................. 27
7.3.9 LINE-IN to REC-OUT Circuit measurement................................................................. 28
7.3.10 Recorder-in to Line-out measurement ........................................................................... 29
7.3.11 TELEPHONE-IN to LINE-OUT Circuit measurement .............................................. 30
7.3.12 Control line test with mode switch (A)........................................................................... 31
7.3.13 Control line test with mode switch (B)........................................................................... 32
7.3.14 System volume control test.............................................................................................. 33
7.3.15 AUDIO CONTROL IN to LINE-OUT via AFS circuit of CPSU measurement ..... 34
7.3.16 Functional AFS test of the LBB 3310/10 ....................................................................... 35
7.4 Measuring spots CPSU board with signal description................................................................. 36
7.5 Measuring instructions for the Delegate and Chairman unit...................................................... 37
7.5.1 Supply current .................................................................................................................... 37
7.5.2 Internal supply voltages..................................................................................................... 37
7.5.3 Unit presence...................................................................................................................... 37
7.5.4 Unit type.............................................................................................................................. 37
7.5.5 Microphone switch and light-ring..................................................................................... 37
7.5.6 Internal signals for Delegate and Chairman units........................................................... 37
7.5.7 Internal signals only for Delegate Units........................................................................... 38
7.5.8 Chairman Only mode........................................................................................................ 39
7.6 Measuring spots Delegate and Chairman board with signal description .................................. 40
8 New microphone assembly on an old delegate-/ chairman unit................................................................. 41
8.1 Description....................................................................................................................................... 41
8.2 Implementation ............................................................................................................................... 41
8.3 Electrical modifications................................................................................................................... 41
8.3.1 Service microphone assemblies identification................................................................. 41
8.4 Field changes of components on the main board ........................................................................ 42
8.4.1 Delegate- and chairman unit component values............................................................. 42
8.4.2 Diagram and board layout of HW 01-02......................................................................... 42
9 Replacement of the microphone capsule....................................................................................................... 43
9.1 Preparation....................................................................................................................................... 43
9.2 Disassembly ..................................................................................................................................... 43
9.3 Re-assembly ..................................................................................................................................... 43
10 Trunk cable interconnections.......................................................................................................................... 44
10.1 Pin numbers delegate- and chairman extension trunk cable ...................................................... 44
10.2 LBB 3316/00 – CCS800 extension cable and connectors........................................................... 45
11 Mounting instruction new CPSU board in old LBB 3310/00...................................................................... 46
11.1 Needed tools and parts ................................................................................................................... 46
11.2 Drilling instructions......................................................................................................................... 46
12 Spare parts......................................................................................................................................................... 47
12.1.1 Ordering spare parts ........................................................................................................ 47
12.2 CPSU spare parts list....................................................................................................................... 47
12.2.1 LBB 3310/x0 CPSU – Mechanical spare parts ............................................................. 47
12.2.2 LBB 3310/00 CPSU – Printed board assemblies.......................................................... 47
12.2.3 LBB 3310/10 CPSU – Printed board assemblies.......................................................... 47
12.2.4 LBB 3310/x0 CPSU – Printed board spare parts.......................................................... 48
12.3 Delegate- and chairman unit spare parts list................................................................................. 48
12.3.1 LBB 3330/x0 Delegate unit – Mechanical spare parts
LBB 3331/x0 Chairman unit – Mechanical spare parts ............................................... 48
12.3.2 LBB 3330/x0 Delegate unit – Service assemblies
LBB 3331/x0 Chairman unit – Service assemblies....................................................... 49
12.3.3 LBB 3330/x0 Delegate unit – Printed boards spare parts
LBB 3331/x0 Chairman unit– Printed boards spare parts ........................................... 49
12.4 Microphone head spare parts......................................................................................................... 49

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13 Illustrations........................................................................................................................................................ 51
13.1 Exploded view CPSU ..................................................................................................................... 53
13.2 Board layout CPSU......................................................................................................................... 54
13.3 Measuring points CPSU board ...................................................................................................... 55
13.3.1 Bottom view CPSU board section mounted in top cover............................................ 55
13.4 Circuit diagrams CPSU (sh 1/4) — Supply and logic................................................................... 56
13.5 Circuit diagrams CPSU (sh 2/4) — Gain control and mode select ............................................. 57
13.6 Circuit diagrams CPSU (sh 3/4) — Audio input and output........................................................ 58
13.7 Circuit diagrams CPSU (sh 4/4) — External microphone input ................................................. 59
13.8 Board layout AFS PCB ................................................................................................................... 60
13.8.1 Jumpers and connectors................................................................................................... 60
13.9 Exploded view delegate/ chairman unit ....................................................................................... 61
13.10 Board layout delegate unit.............................................................................................................. 62
13.11 Measuring points delegate and chairman unit.............................................................................. 63
13.12 Circuit diagram delegate unit......................................................................................................... 64
13.13 Board layout chairman unit............................................................................................................ 65
13.14 Circuit diagram chairman unit....................................................................................................... 66
13.15 Microphone assembly..................................................................................................................... 67
13.15.1 Exploded view microphone head................................................................................. 67
13.15.2 Led diagram and board layout...................................................................................... 67
13.15.3 Wiring of the microphone assembly ............................................................................ 67

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1 General information
1.1 Document history
Rev. edition Changes
00-0350 First edition
01-0501 Adding note p44 and correction of some service parts service code numbers p47
1.2 About this manual
This manual is intended for service engineers involved in maintenance and repair of Bosch ‘CCS 800 Ultro’ and Philips
‘CCS800 Discussion’ system.
This manual is a revised edition of the CCS800 service manual 4822 861 11006.
This manual supplies information about the maintenance and repair of the LBB 3310/xx, , LBB3330/xx, and LBB 3331/xx
discussion system devices and is supplementary to the “Instructions for Use” of this equipment. Information from the
“Instructions for Use” is in general not copied to this manual. The “Instructions for Use” and this “Service manual” should
therefore always be used together.
1.3 Related documentation
•‘Installation and Operating manual’ CCS 800 Ultro. Document Nr.: 3922 988 5428x
In this manual you find all technical-, installation and configuration data.Use this manual together with the service
manual.
•Product Survey Congress Yearbook. Document Nr.: 3922 880 21012
In this document are only the first line spare parts listed.
1.4 Alerts
In this manual, four types of alerts are used. The alert type is closely related to the effect that may be caused when it is not
observed. The alerts – from least severe effect to most severe – effect are:
•Note
Alert containing additional information. Usually. Not observing a note alert does not result in damage to the
equipment or personal injuries.
•Caution
The equipment can be damaged if the alert is not being observed.
•Warning
Person can be (severely) injured or the equipment can be seriously damaged if the alert is not being observed.
•Danger
Not observing the alert can result in death.
1.5 Policy & Procedures
1.5.1 Repair Policy
For defective CCS800 products the general repair procedure is valid. Apply RMA request form (see example chapter 1.5) to
MDB/ Selectron. RMA forms available via BOSCH Security Systems ‘Extranet’ for authorized service organizations.
Service partners are requested to contact the Service department Congress in case of questions and any help.
For authorized service organizations are spare parts to obtain via order desk ‘Spares Logistics Breda’ (SLB).
1.5.2 Warrantee conditions
In-Warranty period is thirty-six (36) months from the date of acceptance or start of use but in no event more than forty-
two (42) months as from the production date (see product type plate) of dispatch from BOSCH Security Systems.
“Dead on Arrival” (DOA) products: For these products MDB/ Selectron will offer a replacement of a brand new product.
MDB/ Selectron or BOSCH Security Systems Breda is free to credit you in case of any damage to the product, which is
not reported by the NSO / BOSCH Security Systems Authorized service partner.
Epidemic failures: In case of a confirmed epidemic failure (and only BOSCH Security Systems Breda can judge if a fault is
epidemic) the NSO / BOSCH Security Systems authorized service partner will be informed via separate letter, fax or other

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mail showing reasons, time schedule and procedures to follow. Costs involved for corrective material to solve the epidemic
failure are for the account of BOSCH Security Systems. Other related costs for the corrective action have to be agreed
upon by the NSO / service partner and BOSCH Security Systems service Breda. It is not allowed to start local corrective
actions without consulting BOSCH Security Systems service Breda.
1.5.3 Service period
The service period for the products will be 5 years after the year the product status has been changed to ‘Sales only’. For a
non-repairable type number (exchange on type number level in case of defects) the support strategy for the remaining
service period will be reconsidered at the moment the regular production will be ceased and the product is deleted from
the catalogue. When the replacement on type number level is continued in case of defects, the delivery of a type number
with the same fit and function will be guaranteed during the above mentioned service period. But not necessarily the same
type number.
1.5.4 Type number survey
Family Type number 12 NC Short description Repair policy
CCS800 LBB3310/00 8900 331 00001 Control unit and power supply unit Central repair
CCS800 LBB3310/00D 8900 331 00021 Control unit and power supply unit UL Central repair
CCS800 LBB3310/00 8900 331 00005 Control unit and power supply unit (Bosch) Central repair
CCS800 LBB3310/10 8900 331 01001 Control unit and power supply unit with AFS (Bosch) Central repair
CCS800 LBB3311/00 8900 331 10005 19" mounting brackets (Bosch) No repair
CCS800 LBB3312/00 8900 331 20005 Suitcase for 10 discussion units (Bosch) No repair
CCS800 LBB3312/10 8900 331 21005 Transport suitcase (Bosch) No repair
CCS800 LBB3316/00 8900 331 60005 Installation Cable Kit 100m (Bosch) No repair
CCS800 LBB3316/05 8900 331 60505 Extension Cable Assembly 5m (Bosch) No repair
CCS800 LBB3316/10 8900 331 61005 Extension Cable Assembly 10m (Bosch) No repair
CCS800 LBB3330/00 8900 333 00001 Delegate unit Central repair
CCS800 LBB3330/00 8900 333 00005 Delegate unit (Bosch) Central repair
CCS800 LBB3330/50 8900 333 05001 Delegate unit with long microphone Central repair
CCS800 LBB3330/50 8900 333 05005 Delegate unit with long microphone (Bosch) Central repair
CCS800 LBB3331/00 8900 333 10001 Chairman unit Central repair
CCS800 LBB3331/00 8900 333 10005 Chairman unit (Bosch) Central repair
CCS800 LBB3331/50 8900 333 15001 Chairman unit with long microphone Central repair
CCS800 LBB3331/50 8900 333 15005 Chairman unit with long microphone (Bosch) Central repair

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1.6 Example RMA request form

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2 Introduction
2.1 LBB 3310/00 Control and Power Supply Unit (CPSU)
The CPSU is the heart of the discussion system, which controls the microphones of the chairman and delegate units as
well as providing facilities for audio inputs and outputs. It also supplies the power for the CPSU, chairman unit(s) and
delegate unit(s).
2.1.1 Block diagram CPSU

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2.2 LBB 3310/10 Control and Power Supply Unit with AFS
This model CPSU has additional an Acoustic Feedback Suppression PCB inside.
2.2.1 Block diagram CPSU with AFS

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2.2.2 Audio level diagram CPSU

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2.3 AFS module LBB 3310/10)
2.3.1 Board function
The AFS module uses a DSPCPU from Philips Semiconductors; which runs at 166 MHz.
The application software stored in flash memory (4Mbyte) determines the board functional behavior.
The firmware can configure the audio interface and perform simple control functions. The download of the firmware is
performed in a factory environment.
In CCS800 the module is included in the signal chain.
After power-up the board will boot from the on-board boot-EEPROM, copy the program available in flash ROM into
SDRAM, and execute the program code in SDRAM.
2.3.2 Block diagram AFS board
The module supports 4-channel analog input and 2-channel audio output. I2C is provided for control of configurable
parameters from an additional board or for indications on other boards.
The EEPROM is used as boot-PROM to obtain power-up configuration data (PLL ratio, memory aperture, refresh rate,
XIO configuration etc.).

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2.4 LBB 3330/00 Delegate Unit
This unit provides the microphone, unit loudspeaker and headphones facilities for the delegates using the CCS 800
discussion system. The headphone connections are interconnected with the loudspeaker. When one or both headphone
connections are used and the microphone is not on, the loudspeaker is switched OFF. It has a protected loop-through
interconnection. In case of disconnection or interruption of the system cable to the next unit, the system cable will
automatically be terminated with the correct impedance.
2.4.1 LBB 3330/50 Delegate Unit with Long Microphone Stem
Ditto with a microphone stem of 480 mm instead of 310 mm.
2.4.2 Block diagram delegate unit

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2.5 LBB 3331/00 Chairman Unit
This unit provides the microphone, unit loudspeaker and headphones facilities for the chairman using the CCS 800
discussion system. Pressing the microphone button always activates the chairman microphone. Pressing the priority button
will deactivated all active delegate units and activates the chairman’s microphone. Release of the button will either leave
them deactivated or activates them again (depending on the setting of the chairman unit). Pressing the priority button may
be indicated by a chime tone.
Further equal to LBB 3330/00.
2.5.1 LBB 3331/50 Chairman Unit with long Microphone stem
Ditto with microphone stem of 480mm.
2.5.2 Block diagram chairman unit

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2.6 Audio level diagram delegate and chairman units

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3 Controls and indicators
3.1 Control and Power Supply Unit (CPSU)
Top Function
On/OFF button Switches the CPSU ON or OFF
Green LED (B1) Indicates if the CPSU is switched ON or OFF
Left rotary switch (S2) Microphone-mode switch. To select the mode for the delegate
microphones. In test position all light-ring indicators lit if all units are
properly connected.
Middle rotary switch (S3) Loudspeaker volume control of the chairman and delegate units.
Right rotary switch (R201) Volume control for the built-in loudspeaker in the CPSU or a connected
headphone to monitor the discussion.
Headphone socket (X8) Headphone socket 3.5mm with built-in switch.
Rear Function
Trunk in/ out (X2, X3) 2x 7p DIN female socket for trunk cables to delegate- and chairman units
Microphone (X9) 3p XLR female socket for external microphone input
Telephone and Insertion (X11) 4x Cinch sockets for in -/ output
Recorder, Tape and Line (X12) 6x Cinch sockets for in -/ output
Microphone gain control potentiometer (R199) To adjust the sensitivity of the microphone input connector X9.
Recorder gain control potentiometer (R200) To adjust the sensitivity of the recorder input connector X12
Insertion switch (S1) Position “1” : loop through; Position “0” : insertion not used
AFS switch (S4), LBB 3310/10 only Position “1” : AFS mode; Position “0” : normal mode

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3.2 Delegate and chairman units
Top
Microphone Electret microphone with build-in plop and windshield, mounted on a
flexible stem, complete with a red LED light-ring
Light-ring around the microphone Indicates if microphone is switched ON
Button (S2) Microphone ON button
Red LED Indicates if microphone is switched ON
Rear
Trunk input Cable, 2 meter, with 7-pole DIN-connector.
Trunk output Loop-through output socket, 7-pole DIN.
Side
Thumbwheel (R54) Rotary volume control for headphones.
Headphone jack s(X6/X7) 2 x 3.5 mm stereo jack headphone sockets.
Inside
Adjustment microphone capsule (R72) Potentiometer to adjust the sensitivity of the microphone (Access via
bottom hole. See chapter 5).
Additional for chairman units
Top
Button (S1) Priority function (chime tone)
Bottom
Small bracket at cable entry Hides the priority and chime mode switch (see “Instructions for use”).
2 Switches behind bracket Delegate microphones off at priority (S37)
Chime en-/disable switch (S42)

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4 Technical data
4.1 Power supply
Specification
Type of power supply: 40W single output, universal input switching power supply
Mains input voltages: 90 .. 264Vac
Input frequency range: 47 .. 63Hz
Max. input current : 0.9A at 100Vac or 0.3A at 240Vac
Nominal output voltage: 24Vdc
Rated output load: 1.7A
Dimensions: 125mm x 75mm
Danger
Heat sink is electrical connected to live of mains input depending on polarity!
4.1.1 Additional technical specification for test environment:
Load range
Output Min. load Rated load Peak load Voltage
accuracy
+24V 0A 1.7A 2.5A 24 ±0.6V
For a practical load test, connect e.g. a resistor of 15 Ohm (min. 40W) between the terminals +24V and GND.
Line regulation
Line input Load Regulation
Input change 90 .. 264Vac 1.7A < ±1%
Ripple and noise
Output Test Conditions
24V with 1.7A load <1% p-p (rated load) Oscilloscope with 15Mhz limited
bandwidth
AC input pin assignment K1 1 — 3
L N
Line Neutral

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AC input fuse F1
Replace power supply unit in case of fuse failure!
DC output pin assignment K2 1 2 3 4 5 6
+24V +24V +24V GND GND GND
5 Microphone stem adjustment
Microphone stem
When the microphone stem assembly has to be replaced, it is required that the input level of the microphone is adjusted
again by use of the preset potentiometer R72. This is due to the spread in sensitivity of the microphone capsule (approx.
±4dB).
Procedure
The adjustment is practical procedures to compare factory-adjusted units with units were the microphone stem is replaced
and to be tuned to the system level again.
Test set-up
•Audio sine wave generator
•Home made loudspeaker reference source or a professional sound level calibrator unit “A” (see figure below).
To make a home made reference source, mount inside an (empty) microphone head e.g. a paging bleeper as ref. Loudspeaker.
•CPSU.
•AC mV meter.
Measurements
Test procedure Comment
1 Connect the CCS800 unit with the CPSU. Select only one active microphone on the CPSU!
2 Connect to the ‘Line out’ of the CPSU the AC
mV meter
X12, see chapter 3.1.
3 Adjust the audio source to approx. 1kHz. The audio level of the loudspeaker should be distortion free and
at a level of speaking distance.
Take care that no acoustic nuisance from outside influences the
measurements.
4 Place the mic. of a factory adjusted CCS800
unit close to the loudspeaker on a fixed distance.
Make from an old DCN or CCS800 microphone head housing
an audio reference source (A)
Of importance is that for all measurements the distance
between loudspeaker and microphone is equal.
4a Measure the audio level on the AC meter. Take this level as ref. for the CCS800 units to be adjusted.
Repeat the ref. measurement for a check with other unit(s).
(The factory level adjustment is ± 1,5 dB)