DITTING KED 640 User manual

Page 1age
1
Operating Instructions
KED 640 Espresso Grinder
”Grind-on-Demand“
P

Page 2
Dear customer / service personnel,
the Double Espresso Grinder „KED 640” is a fully automatic espresso coffee
grinder of the proven Ditting quality.
We have developed this product with over 80 years of experience in the manu-
facture of coffee grinders assuring you of high quality grinding of all kinds of
espresso and other types of coffee beans.
Espresso as the base of various coffee specialities requires a very precise
grind. With the „KED 640“ you can now grind two different kinds of espresso
(like decaf and regular) simultaneously in one machine.
Read through and observe the operating instructions, so you and your custom-
ers will thoroughly enjoy the ”KED 640”. Follow the safety instructions at all
time and also advise your personell.
Please store the instructions in a safe place. If anything is unclear or addi-
tional information is required, please contact your authorized dealer or us as
the manufacturer.
We will be pleased to advise you further.
We wish you unlimited pleasure and success with our product.
Ditting Maschinen AG

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Table of contents
1. Safety 4
1.1 Symbols 4
1.2 Safety Instructions 4
1.3 Purpose of Use 5
1.4 User Requirements 5
2. Technical Data 5
3. Description 6
4. Set-up and Initial Adjustments 7
4.1 Place of Installation 7
4.2 Locking in the hoppers 7
4.3 Electrical Installation 7
4.4 Adjustment of the port-a-filter rests 7
4.5 Adjustment of the cleaning alarm 8
5. Operation 8
5.1 Instructions for the first grinding steps 8
5.2 Operating the grinder 8
5.3 Interruption of grinding (break-function) 9
5.4 Software Menu 9
5.5 Describtion of the software chapters 16
6. Cleaning 17
6.1 Cleaning with GRINDZTM Grinder Cleaner 17
6.2 Cleaning the Drip Tray and the Hoppers 18
6.3 Cleaning the Grinder Placement Surface 18
6.4 Cleaning the Grinder Casing 18
7. Maintenance and Repair 18
7.1 Grinding fineness adjustment with the grinder switched ON 18
7.2 Taking off the grinder cover 19
7.3 Basic Adjustment of The Interior Grinders 19
7.4 Cleaning of the Grinding Mechanism 20
7.5 Grinding Disc Exchange 20
7.6 Removal of The Integrated Grinder 20
8. Trouble Shooting for Operating Faults 20
8.1 Safety Devices of the Grinder 20
8.2 Operating Fault 21
8.3 Alarm Signals Showing in The Display 22
9. Spare Parts 24
10. Wiring Diagrams 25
10.1 Diagram 240 V 50 Hz 25
10.2 Diagram 230V 50Hz 26
10.3 Diagram 240V 50Hz 27
11. Certificate 28
12. Warranty Conditions 28
Page Page

Page 4
Always remove the electrical plug from the outlet prior to removing the hopper
or conducting maintenance or cleaning work on the grinder.
Never operate a grinder with a damaged electrical cord. Inspect the grinder
regularly for damages of the electrical cord, plug, etc.
Any required repairs may only be conducted by authorized service personell.
For this reason, please contact a customer service repair facility, your dealer
or us directly as the manufacturer.
Do not exceed the maximum allowable continuous grinding time of 20 min.
Afterwards, allow the grinder to cool off before the next operation. Do not ex-
ceed the maximum allowable running cycle of 4 sec. ON, 6 sec. OFF (6 double
shots per minute, S3 40%) for 230V / 50Hz, and 6 sec. ON, 15 sec. OFF (4 double
shots per minute, S3 25%) for 115V / 60Hz.
Do not make any modifications or alterations to the grinder. The manufacturer
assumes absolutely no liability for damages occurring from failure to observe
these instructions.
Children cannot appreciate the dangers that can exist in the operation of elec-
trical grinders. For this reason never leave children unsupervised with elec-
tronic appliances such as this grinder.
Never operate the grinder in damp or wet surroundings.
Never operate with wet hands.
1. Safety
Please read carefully and observe the following
safety instructions. Failure to do so can result in dam-
age to the grinder and danger to the user.
1.1 Symbols
The following two symbols are used in these operating instructions:
Safety Instruction:
Imminent accident danger if you fail to observe.
General Instruction:
Failure to observe can result in damage to the grinder
and optimum operation cannot be guaranteed.
1.2 Safety Instructions
Only whole roasted coffee beans may be ground in the KED 640!
When unpacking please inspect whether the power supply (voltage) com-
plies with the grinder voltage on the manufacturer’s name plate at the bot-
tom of the grinder.

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2. Technical Data
Type KED 640
Voltage/Frequency 230-230V 50/60Hz
240V 50Hz
100-115V 50/60Hz
Rotation
230-240V 50 Hz 1420 rpm
110-115V 60 Hz 1640 rpm
Sound Emission
Idle Operation 65 dB
Operation 85 dB
Pre-Fuse 16 A-slow
Motor Fuse 5x20 10A slow
Overload Circuit Breaker
200-240V 4A T
110-115V 7A T
Max. Permissible Running 230V: 4 sec. ON, 6 sec OFF
Time of the Grinder 115V: 6 sec. ON, 15 sec. OFF
Dimensions in mm B 368, H 590, T 300
Weight 26 kg (57.3 lbs)
Hopper Capacity 2 x 750 g (2 x 1.65 lbs.)
(Please request technical data for other voltages and frequencies from the manufacturer or dealer)
1.3 Purpose of Use
Only whole roasted coffee beans may be ground in the KED 640 grinder. Pay
attention to use only clean and unground coffee. Never use the grinder to
grind other products or objects.
1.4 User Requirements
No special requirements are necessary for the user of this grinder. It is nev-
ertheless a prerequisite that these operating instructions have been carefully
read and understood and that all instructions provided are observed. In addi-
tion safety-conscious operation is expected.

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3. Description
The main components and operating elements are pictured in the illustration.
Pos. 1 Hopper with lid and finger protection
Pos. 2 Lock screw for hopper
Pos. 3 Grinding fineness adjustment
Pos. 4 Brake for grind adjustment
Pos. 5 Grinder cover with lock screw
Pos. 6 Display
Pos. 7 Pre-selection button „single espresso“
Pos. 8 Pre-selection button „double espresso“
Pos. 9 „Program“-button
Pos. 10 Spout
Pos. 11 Port-a-filter mounting
Pos. 12 Port-a-filter rest
Pos. 13 Fastening screw for port-a-filter rest
Pos. 14 Start / Stop switch
Pos. 15 Drip tray (with hopper slides underneath)
Pos. 16 Main switch (at the back of the grinder)
1
4
5
6
7
15
14
2
3
8
10
12
16
11
13
9

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4.3
El
ectr
i
ca
l
I
nsta
ll
at
i
on
Prior to plugging in observe the following safety instructions:
Protect your device with separate pre-fuses (not
included in the scope of delivery) according to
the information provided under point 2 „Technical
Data“
Make sure that the pre-fuse is not overloaded by
other devices (e.g. fan heaters, deep freezers, etc)
Check whether the main voltage and frequency
correspond to the information on the rating plate
underneath the grinder.
Insert the plug into the corresponding grounded outlet.
4.4 Adjustment of the port-a-filter rests
The grinder is designed so that all different port-a-filters from various
espresso machines fit into the rest for hands-free grinding operation.
4.4.1 Keep the grinder switched off. Slightly loosen the allen screws
(pos. 13) with the included allen screw driver size 3mm and pull down
t
he port-a-filter rest (pos. 12).
4.4.2 Push the port-a-filter of your espresso machine onto the start/stop
switch between the port-a-filter mounting (pos. 11) and the rest (pos 12).
Now push up the port-a-filter rest until the port-a-filter holds on its own.
Now refasten the screws. The adjustment is correct when the port-a-
filter stays independently remains in the mounting.
4. Set-up and Initial Adjustments
You have received your grinder in operating condition. Now you only need to
place it in a safe place and connect it to the main power socket. Proceed as
follows:
4.1 Place of Installation
Place the grinder on a level, vibration-free surface.
Never operate the grinder in moist, or even worse, in
wet surroundings!
4.2 Locking in the hoppers
Set the hopper into the bayonet socket. Grab the hopper with both hands and
turn it carefully in clockwise direction, until the bayonet locks in.
Always loosen the grind adjustment brakes and turn
both adjustments to fine (setting 0) when locking in the
hoppers. Turning the grind adjustment ring repeatedly
without loosening the brake could damage the interlock.
Fasten the lock screw for the hopper (pos. 2) to prevent the hoppers from un-
authorized removal.

Page 8
In case the port-a-filter rests does not fit your espresso
machine’s port-a-filter, please contact us or your local
dealer. We will be happy to send you a different rest.
4.5 Adjustment of the cleaning alarm
The software of the KED 640 has an integrated cleaning alarm which is activat-
ed at a preset amount of shots taken. This alarm should remind you of cleaning
the grinder regularly in order to increase the discs‘ lifetime.
DITTING recommends: The cleaning limit should be set
to the amount of shots that are ground per week. (For
the set-up of the limit and for resetting the counter after
cleaning see chapter 5.5.9)
5. Operation
Once the grinder is set up and ready to operate a grinding test should be car-
ried out.
5.1 Instructions for the first grinding steps
Only use the KED 640 espresso grinder for whole roasted
coffee beans.
Observe the safety instructions under 1.2!
Never exceed the maximum permissible continuous
operating cycle of 4 sec ON, 6 sec OFF (S3 40%). Also do
not exceed the maximum allowable continuous grinding
time of 20 min. Afterwards, allow the grinder to cool
down before the next operation.
5.2 Operating the grinder
5.2.1 Switch on the grinder at the back of the casing (pos. 16).
5.2.2 Open the hopper and pour whole roasted espresso beans into the hopper
Never pour in coffee powder which would result into
immediate blocking of the discs.
5.2.3 Adjust the grinding fineness by pulling the grind adjustment interlock
(pos. 4) and turning the ring (pos. 3) including the hopper to the desired posi-
tion. Note that „0“ is the finest setting and „10“ is the coarsest. Let go and
re-lock the brake to fix the setting.
Test runs have proved grind adjustments 1 – 4 to be the
most common settings for espresso depending on the or-
igin, roast and blend. This should be taken into account
when adjusting the grinder for the first time.
5.2.4 For the first test run the grinding time settings are pre-programmed for
single shots to 2.0 sec and for double shots 4.0 sec. For changing these set-
tings please see chapter 5.3.
coarse
fine

Page 9
5.2.5 Choose the single or double pre-select-button according to your
port-a-filter. The LED shows which button is selected.
Single espresso left grinder
Double espresso left grinder
Single espresso right grinder
Double espresso right grinder
5.2.7 Now brew a test portion of espresso using your machine. If the result
is unsatisfactory, alter the adjustment again by varying the grinding time and
grinding fineness until the best coffee results have been achieved.
5.3 Interruption of grinding (break-function)
If the grinding process is interrupted before the set grinding time has expired,
the LED in the active pre-selection button flashes. The grinding process can
be re-started by pushing the port-a-filter back into the mounting. The missing
quantity is ground. If this is not desired push the pre-selection button and the
entire set grinding quantity or grinding time is available once again.
5.4 Software Menu
The following overview shows the handling of the KED 640´s software.
5.2.6 Push your espresso machine’s port-a-filter into the port-a-filter mounting
(pos. 11/12) so that the grinding process starts.
The first operation will not result in the desired amount
of espresso because the grinder has to fill up with
ground coffee. The second shot should give the correct
result.

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Quick Manual KED 640 Basic Functions of the Buttons
PROG.
Enter (go into a lower software menu level) P5
right
go foreward in menu P8
left
decrease values in menu ( - button) P6
left
increase values in menu ( + button) P7
right
go back in menu P9
Display

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Main Menu Sub Menu
PROG.
press
PROG.
press
DITTING
GRINDER READY 1) PROGRAM DOSE GRINDER N° 1
DOSE N° 1 2.000s
(left grinder - single shot)
GRINDER N° 1
DOSE N° 2 4.000s
(left grinder - double shot)
GRINDER N° 2
DOSE N° 1 2.000s
(right grinder - single shot)
GRINDER N° 2
DOS N° 2 4.000s
(right grinder - double shot)
right
press
right
press
right
press
right
press
PROG.
press
time blinking
PROG.
press
save
left
left
Sec.
Sec.
PROG.
press
time blinking
PROG.
press
save
left
left
Sec.
Sec.
PROG.
press
time blinking
PROG.
press
save
left
left
Sec.
Sec.
PROG.
press
time blinking
PROG.
press
save
left
left
Sec.
Sec.
PROG.
press
2) DOSE COUNTER GR1: SHOTS1
0000002
(left grinder - 2 single shots)
GR1: SHOTS2
0000120
(left grinder - 120 double shots)
GR2: SHOTS1
0002123
(right grinder - 2123 single shots)
GR2: SHOTS2
0000020
(right grinder - 20 double shots)
right
press
right
press
right
press
right
press
PROG.
press
3) ALARM / RECORDS NO RECORDS
right
press
or ALARM RECORDS e.g.
GRINDER 1
BLOCKED GRINDER 1
FAN TOO SLOW
right
press
right
press
Quick Manual KED 640 Menu
right
press
right
press counter volumes represent examples

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Main Menu Sub Menu
PROG.
press
4) LANGUAGE, REL
SW, SERIAL N° 4-1) LANGUAGE ENGLISH 4-2) SW RELEASE 0.07 4-3) SERIAL N° 1234
right
press
right
press
right
press
PROG.
press
PROG.
press
SAVE
left
left
CHANGE LANGUAGE
CHANGE LANGUAGE
LANGUAGE BLINKING
PROG.
press
5) RESET RESET
GRINDER N° 1 RESET GRINDER N° 2 RESET ALARM RECORDS RESET CLEANING COUNTER
RESETTING
GRINDER N° 1 RESETTING GRINDER N° 2 RESETTING ALARM RECORDS RESETTING CLEANING COUNTER
right
press
right
press
right
press
right
press
PROG.
press
PROG.
press
PROG.
press
PROG.
press
set dose counter
of left grinder back to 0 set dose counter of right grinder back to 0 delete all alarm records set cleaning counter back to 0
Quick Manual KED 640 Menu
right
press
right
press
only service menu

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Main Menu Sub Menu
PROG.
press
6) SETUP 6-1) CLEANING AL.
NO
6-1) CLEANING AL.
NO YES
6-2) CLEANING AL.
1000 6-3) SERIAL N° 1234
right
press
right
press
right
press
only changable
in factory with super pin
PROG.
press
PROG.
press
NUMBER blinking
PROG.
press
SAVE
left
left
PROG.
press
SAVE
left
left
YES
NO
or
Quick Manual KED 640 Menu
right
press
only service menu

Page 14
Main Menu Sub Menu
PROG.
press
7) TEST 7-1) INPUT, DIP
SWITCH, FAN 7-2) TRIAK, RELAY CURRNET 7-3) BUTTONS 7-4) DISPLAY
SIC SW1 SW2 MC1
OFF OFF OFF OFF
F1 (HZ) F2 (HZ)
ON 120 OFF 0
GR1=OFF RL=ON
I = 4.89A
right
press
right
press
right
press
right
press
PROG.
press
PROG.
press
PROG.
press
PROG.
press
PROG.
press
PROG.
press
7-5) POWER
SUPPLY 7-6) RS232 INTERFACE
right
press
right
press
rightright
KEYB=
(checking the function of the
buttons with numbers) LCD
(testing all display dots)
LED
(testing all LED’s)
SIC: Lid safety switch
SW1: switch left grinder
SW2: switch right grinder
MC1: 230V / 115V
ON: Contact closed
activates / deactivates
the triak of the grinder
press
left
press
right
LCD
press
right
press
right
BUZZ
(testing the alarm)
press
right
activates / deactivates
the relayof the grinder
press
left
press
right
F1: FAN 1
(HZ): Frequency of F1
F2: FAN 2
(HZ): Frequency of F2
press
right
V-SUPPLY = 27.3V testing the RS 232
Interface
right
right
for grinder 1
for grinder 2
or
for P5
press
for P6
left
press
for P8
right
press
for P7
left
press
for P9
right
END
Quick Manual KED 640 Menu
right
press
only service menu

Page 15
Main Menu Sub Menu
PROG.
press
8) CHANGE
PASSWORD PASSWORD
XXXXXX
right
press
right
press
the first X blinking
SAVE
left
left
for next number
and
for saving in the end
PROG.
press
9) CLEANING COUNT.
RESET
DITTING
GRINDER READY
9-1) CLEANING AT
1000
right
press
PROG.
press
NUMBER blinking
PROG.
press
SAVE
left
left
9-2) RESET
RESETTING
CLEANING COUNTER
right
press
PROG.
press
END MENU
Quick Manual KED 640 Menu
right
press
right
press
only service menu

Page 16
Pressing the PROG-button once enters the user menu
(menu chapters 1-4 and 9).
Pressing the PROG-button for appr. 5 seconds and typing
in the password enters the service menu (menu chapters
1-8).
Password:
Until serial number 18571: „666 666“ (software version V0.12)
From serial number 18572: „000 000“ (software version V0.13)
5.5 Describtion of the software chapters
5.5.1 Program Dose
Adjust and change the grinding time for single and double dosing for both
grinders.
GRINDER N°1 = left grinder
GRINDER N°2 = right grinder
DOS N°1 = single espresso
DOS N°2 = double espresso
The time can be set in 0.005 sec steps. A change of 0.1 seconds adds or takes
away approximately 0.5 gram of coffee. (This reference value can vary for dif-
ferent coffees and roasting degrees.)
Press and hold the PROG-button after changing the time to quick-exit the
menu. The display will show „DITTING GRINDER READY“.
5.5.2 Dose Counter
Read the counters for single and double shots for both grinders.
5.5.3 Alarm Records
Alarms are saved in the order of appearance (the last one to appear first in
line). 20 alarms can be saved, the 21st overwrites the oldest. For a detailed
describtion of all alarms with causes and remedies please see chapter 8.3.
5.5.4 Language, Software Release, Serial Number
Change the language of the menu (Italian, English, French, German, Spanish).
Read the software release number and serial number of the grinder.
5.5.5 Reset (only in the service menu)
All counters and alarm records can be set back to Zero or deleated respec-
tively.
5.5.6 Set up (only in the service menu)
Set up the cleaning alarm:
• Switch ON or OFF the cleaning alarm.
• Set the Cleaning Alarm Limit, which is the max. allowable limit that can
be set in menu point 9.
5.5.7 Test (only in the service menu)
Check the functionality of the different electrical components and functions in
the grinder. This menu point should help service partners to locate potential
malfunctions.
5.5.8 Change Passwort (only in the service menu)
Change the passwort to your individual 6-digit number. (See chapter 5.4.)

Page 17
5.5.9 Cleaning Counter Reset
Set the cleaning counter to the appropriate amount of shots so that the alarm
reminds the user to clean the discs on a regular basis. (See chapter 4.5.)
Set the counter back to Zero after cleaning the grinder.
6. Cleaning
We recommend cleaning your espresso grinder regularly. Only use food-safe
cleaning detergents.
Always pull the main plug from the socket before carry-
ing out maintenance or cleaning work on the grinder.
Observe the safety instructions under 1.2.
Do not let any foreign object fall into the grinding mechanism.
6.1 Cleaning with GRINDZTM Grinder Cleaner
We recommend cleaning your espresso grinder once a week with our
GRINDZ™ Grinder Cleaner.
DITTING recommends: The cleaning limit should be set to the
amount of shots that are ground per week. ( For the set-up of the
limit and for resetting the counter after cleaning see chapter
5.5.9.)
Remove all beans from the hopper or take the hopper slides from under the
drip tray and push them into the slots in the bayonet adapter. Remove the lock
screw. Now you can take off the hopper.
When taking off the hopper ALWAYS release the grind
adjustment brakes and turn both rings to coarse. This
will block the adjustment. Turning the grind adjustment
ring repeatedly without loosening the brake could dam-
age the interlock.
Grab the hopper with both hands and turn it anti-clockwise until it is released
by the bayonet. Empty the input chute of all espresso beans and vacuum out
the disc casing.
Also empty the hopper and relock it onto the grinder. Take off the hopper slide.
When engaging the hopper into the bayonet ALWAYS
release the grind adjustment brakes and turn both rings
to fine. This will block the adjustment. Turning the grind
adjustment ring repeatedly without loosening the brake
could damage the interlock.
Drop the recommended dose of GRINDZTM (35 - 40g) into the empty grinder
hopper. You can also use the cap of the jar for dosing. A full cap will yield
between 35 - 40 grams.
Turn the fineness adjustment to medium and operate as if grinding coffee
beans.
Once complete, we recommend passing twice as much coffee through to
purge any residue.

Page 18
Set the cleaning counter back to Zero, if the grinder was
cleaned due to the cleaning alarm. (See chapter 5.5.9.)
6.2 Cleaning the Drip Tray and the Hoppers
The hoppers, their lids and the drip tray (without hopper slides) can be cleaned in a dish-
washer or in a bath of water with dish detergent.
Depending on the dish washing detergent the transpar-
ent plastic parts of the hopper can slightly fade out.
6.3 Cleaning the Grinder Placement Surface
6.3.1 Pull out the main plug.
6.3.2 Take off the drip tray.
6.3.3 Tilt the grinder to one side and clean the area on which it stands and the bottom of its
base. Both surfaces must be dry and free of oil and grease.
6.3.4 Reposition the grinder and re-insert the drip tray.
6.4 Cleaning the Grinder Casing
Clean the outside of the casing from time to time using a damp cloth.
Be carefull of sharp edges when cleaning.
There is a risk of injury.
7. Maintenance and Repair
Any required repairs may only be conducted by author-
ized specialist personnel. For this reason, please
contact a customer service repair facility, your dealer or
us directly as the manufacturer.
Always pull the main plug from the socket before carry-
ing out maintenance or cleaning work on the device!
Inspect the grinder regularly for damage, particularly to
the electrical cable, plug,etc.
7.1 Grinding fineness adjustment with the grinder switched ON
Depending on the wear and tear of the grinding discs or after opening the
interior grinder the setting of the finest grind adjustment has to be checked.
Proceed as follows:
7.1.1 Set the grinding fineness adjustment to „0“.
7.1.2 Close and remove the hopper.
7.1.3 Remove the remaining beans from the filler shaft and vacuum out the
grinder casing.
7.1.4 Remove the sealing ring from the filler shaft.
7.1.5 Loosen – do not unscrew – the adjusting screws with the allen key size
2.5 mm.

Page 19
7.1.6 Insert the adjusting handle (service tool) into the filler shaft. The adjusting
handle must engage in the slot into filler shaft’s transverse bar.
7.1.7 Hold the adjusting handle firmly and push the port-a-filter into the port-a-
filter mounting until the grinder switches on.
7.1.8 Whilst the grinder is running, turn the adjusting handle clockwise until a
slight ringing sound becomes audible. Now turn the adjusting handle slightly
anti-clockwise until no further ringing sound can be heard.
It is important to ensure that no grinding disk „rattling“
can be heard at the finest setting! Otherwise the service
life of the discs will be significantly reduced.
7.1.9 Tighten the adjusting screws and remove the adjusting handle from the
filler shaft.
7.1.10 Insert the sealing ring again. If the sealing ring is damaged it must be
replaced.
7.1.11 Replace the hopper and allow it to engage in the bayonet and replace
the lock screw. Open the hopper slide.
7.1.12 Reset the desired grinding fineness.
7.1.13 Push your espresso machine’s port-a-filter into the port-a-filter mount-
ing (pos. 11/12) until the grinding process is switched on.
7.1.14 Only remove the port-a-filter once the grinding process has been com-
pleted. Repeat approximately twice in order to fill the grinder casing with the
re-adjusted ground coffee.
7.2 Taking off the grinder cover
Grind or take out all coffee bean residues. Switch off the grinder and pull the
main plug. Turn both grind adjustment rings to coarse and fix the brakes. Loos-
en the lock screw in the front with the allen screw driver size 2mm. Carefully
lift the grinder cover upwards.
7.3 Basic Adjustment of The Interior Grinders
The basic adjustment to a moderately fine setting has been carried out in the
factory using espresso beans. The following markings have been made on the
grinding mechanism (interior):
Red mark 1: Basic adjustment 0, finest setting and minimum grinding disc
spacing
Red mark 2: Basic factory setting and also the position for installing and re-
moving the lid, in order to achieve the finest setting after positioning the lid.
Red mark 1 Red mark 2

Page 20
7.6 Removal of The Integrated Grinder
For safety reasons the interior grinders are fixed to the casing’s ground plate.
7.6.1 Disconnect the main plug. Close and remove the hoppers. Place the
grinder on its back and unscrew the hex nuts of the motors (three each). Store
the nuts and washers in a safe place. Re-position the grinder on its rubber feet
7.6.2 Take off the grinder cover (see chapter 7.2)
7.6.3 Release the motors‘ plug-in connectors.
Carefully pull the integrated grinder out of the casing.
Do not change any grinder settings. The discs could be damaged when re-
assembling the grinder.
8. Trouble Shooting for Operating Faults
8.1 Safety Devices of the Grinder
Thermal overload circuit breakerThe motor of the grinder is protected by a
thermal overload circuit breaker which interrupts the motor‘s electric circuit
in the event of electric overload. The display shows an alarm signal. Pressing
the PROG-button or the right single shot button releases the grinderback to
operation mode.
Never rotate the grinding discs clockwise further then
the red mark 1, as the grinding discs may otherwise be
damaged.
7.4 Cleaning of the Grinding Mechanism
After opening the grinder cover the grinding mechanism with the discs can be
vacuumed. Check for foreign objects in the grinding gear.
Do not change any grinder settings. The discs could be
damaged when re-assembling the grinder.
Carefully vacuum the grinder casing. Take care no to damage any cables.
7.5 Grinding Disc Exchange
Grinding disc replacement should only be carried out by authorised special-
ists or a customer service centre. The „Repair manual KED 640 grinding disc
replacement and basic adjustment“ can be downloaded for replacing grinding
discs.
Grinding disc replacement may also be carried out using a replacement (AT)
integrated grinder. To do this, order an AT integrated grinder. On receipt of
the AT integrated grinder, remove your integrated grinder from the KED 640
according to chapter 7.6 and install the AT integrated grinder into the KED 640.
Return your old integrated grinder in the packaging.