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CYTOSPIN 3
74010101
Issue No 02
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CELL PREPARATION
SYSTEM
SlWNDONI(>I
Shandon
Scientific
Limited is an IS0 9001 Approved
Company.
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SERVICE MANUAL
information contained in this document is intended for use by
qualified personnel only. The calibration, scheduled servicing and
the removal and replacement of parts should only be undertaken
by personnel who have been formally trained in the appropriate
servicing techniques and procedures.
I
I
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LIFE SCIENCES
INTERNATIONAL
SERVICE IidANUAL RECEIPT
(EUROPE) LTD
SKEET
When you receive this Cytospin 3 Service Manual, please complete the
following:
Company/Agent Name: . ... .. . ..... .. . . . ... .... ... .. .. ... .. .. . ............ ..... ... ... .. .. .. .........
Address: .....................................................................................................
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.
Signature: .... .... . .... . .. ... .. .. .. . .. ..... .. . . . .. ... .. ....L.. ... ..... .. ... ...... ...... ..... ... .. ....... .....
Please return this completed Receipt Sheet to the Service Department at
Life Sciences international (Europe) Ltd by fax (0928 565845) or by letter
post to:
Life Sciences international (Europe) Ltd
International Service Department
Chadwick Road, Astmoor
Runcorn, Cheshire, WA7 IPR
England
These sheets will be used to complete our records and ensure you
receive any amendments as and when they become available.
International Service Manager
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SELANDONCYTOSPIN
3
MICROPROCESSOR
CONTROLLED
CENTRIFUGE
SERVICE:HANUAL
This manual has been designed
as an aid to efficient
servicing
fault
diagnosis
on the Cytospin
3 centrifuge
machine.
In order to get the best
the operators
manual.
results
from the Cytospin
3 please
and
consult
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The service
manual for the Cytospin
3 bench top centrifuge
is designed
to provide
the locally
based engineer
with all the information
he
needs to install
and maintain
the Cytospin
in good running order.
It
is essential
that the maintenance
routines
are followed
so that the
operator
gets the most out of the Cytospin.
In the event of a problem arising,
the section
on Fault Diagnosis
This section
contains
information
designed
to
should be referred
to.
help the service
engineer
locate
and repair simple faults.
For a more
detailed
description
of the operation
of the Cytospin
3, the
Principles
of Operation
section
should be referred
to.
If you think you have identified
and resolved
the cause of a fault,
remember to carry out any calibration
of the part you have repaired
Before handing over the Cytospin
to the
if necessary.
replaced,
operator,
make sure you have checked it out thoroughly
using the
serviceability
test.
Finally,
the manual provides
parts you may need to order.
you with
a comprehensive
list
of
any
Whilst every care has been taken to ensure that the information
contained
in this manual is correct,
no liability
can be accepted
Shandon Scientific
Limited for any loss,
damage or injury
caused
given.
from, the information
any errors
in, or omissions
No part of
All rights
reserved.
recorded,
including
photo-copying,
permission
of Shandon Scientific
this manual may be reproduced
without the express
written
Limited.
ii
or
by
by
or
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AMENDMENTS
Each of these manuals is numbered and listed
against
a manual holder.
Any further
copies
required
for the service
area you are responsible
for will be listed
under the same holder with a different
sequential
number.
As changes in the machine design necessitate
changes in the manual,
amendments will be sent to you to update the text:
These amendments
will
involve
adding and/or changing pages,
the amendment log will help
ensure all are up-to-date.
These manuals can only
Service
Office.
be obtained
through
Runcorn
International
AMENDMENT
LOG
Each time an amendment is
Amendment Number
740-1-g
1
issued,
fill
in the number and date.
Date
Signature
24.4.91
J J Curran
iii
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INDEX
ChaDter
Title
Page No
INSTALLATION
1
PROGRAMMING
THE CYTOSPIN 3
2
SERVICEABILITY TEST
8
DAILY AND WEEKLYMAINTENANCE
11
SAFETY
14
STATIC DAMAGETO MOS DEVICES
14
FAULT DIAGNOSIS AND REPAIR
15
FITTING, TESTING AND CALIBRATION
29
Motor
Lid
Drip tray
Damper adjustment
Guard barrier
Lid catch
Out of balance
switch
Power supply
Heatsink
Nosecone
29
30
31
31
32
32
33
33
34
34
(a)
(b)
(c)
34
34
35
Main PCB
Proximity
switch
Front panel
9
EXPLODEDDIAGRAMSAND PARTS LIST
36
10
LIST OF DRAWINGS
48
11
CIRCUIT DIAGRAMS
49
APPENDIX
PRINCIPLES OF OPERATION
51
(1)
51
51
51
52
52
53
53
54
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
Overview of System
General
Power Supply
Microprocessor
System
Display
and Keyboard Circuits
Motor Drive Circuit
Solenoid
and Relay Drive Circuits
Speed Watchdog and Out of Balance
m,
m,
Hardware Watchdog and
Open Collector
Logic
Motor, Opto Disc,
Lid Lock and
Balance-Switch
iv
55
55
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1
INSTALLATION
1
Unpack the unit and carefully
(electrical
cord).
untie
the mains lead
2
Check the instrument
for signs of damage in shipment (broken
glass,
broken plastic,
dents,
etc).
If something is missing
or damaged notify
Shandon or your supplier
immediately.
Quote the order number(s),
inspection
number, serial
number,
date and number of the invoice.
3
fit a suitable
plug to the mains lead
Where necessary,
Make sure that the earth wire is
(electrical
cord).
connected
and that the mains supply has an earth (ground)
connection.
Instruments
supplied
to France, Germany and North America
are fitted
with plugs during manufacture.
Other customers
should connect
the mains lead to a suitable
rated fused plug
as follows :
Brown wire
Blue wire
Green/Yellow
wire
- Live (L or L2) terminal
- Neutral
(N or Ll) terminal
- Earth (E or Ground) terminal
Make sure that the voltage
rating
on the specification
plate
at the rear of the Cytospin
and on thezinspection
tag are
the same as the mains supply rating.
Switch
the instrument
on by pressing
the power switch.
4
cover.
In
Press the ‘Open Lid I button and open the safety
the event of a power failure,
the safety
cover cannot be
opened using the ‘Open Lid’ button.
The small white cap on
the left-hand
side of the instrument
should be removed.
A
pencil
or rod pushed into the hole and pressed firmly will
Remove the sealed head and set it on
open the safety
cover.
the bench beside
the instrument.
Remove all internal
packing.
5
Unpack the basic
Operator Manual.
kit
and check
against
the items
list
in the
2
PROGRAHHING
THE CYTOSPIN 3
This section
illustrates
how the Cytospin
3 is programmed and how programs may be stored,
viewed and run.
Please go through each example completely
to gain a full
understanding
of how to effectively
use your
Ensure that the Cytospin
lid is closed
before
running this unit.
unit.
(a)
Entering
Speed
and Running
required
a Program
= 1500 rpm, Time required
Operation
N
1
2
3
4
5
6
7
8
9
10
11
Switch
Press
Press
Press
Press
Press
Press
Press
Press
Press
Press
'ON'
'SET TIME'
‘5'
'ENTER'
'SET SPEED'
‘1'
‘5'
‘0'
‘0'
'ENTER'
'LOW'
= 5 minutes,
Acceleration
rate
= low.
Speed
Display
Time
Display
Accel
Display
Audible
Signal
0
0
0
0
0
1
15
150
1500
1500
1500
0
0
5
5
5
5
5
5
5
5
5
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
LOW
3 Set
valid
valid
valid
valid
valid
valid
valid
valid
valid
valid
Audible
key tone
key tone
key tone
key tone
key tone
key tone
key tone
key tone
key tone
key tone
This program may now be initiated,
ie run (Operation
The Cytospin
3 is now programmed.
and/or
it may be stored
in memory with a designated
program number (see (b) below).
12
13
14
15
16
17
Press 'START'
Acceleration
Period
Once Speed Attained
Deceleration
Period
Head Stops Rotating
After 3 Set Audible
Signal
0
O-1500
1500
1500-O
0
1500
5
5
5-o
:
5
LOW
LOW
LOW
LOW
LOW
LOW
valid
key
tone
3 Set Audible
step
Lid
Lid
Lid
Lid
Lid
Lid
12)
Locked
Locked
Locked
Locked
Unlocked
Unlocked
(b)
Storing
(Saving)
a Program in Memory
Program Number 1 designated
Operation
1
2
3
Press
Press
Press
‘SAVE’
Program ‘1’
‘ENTER’
Program
Display
Speed
Display
Time
Display
Accel
Display
0
1
1
1500
1500
1500
5
5
5
LOW
LOW
LOW
Program Number 1 is now entered
into the memory.
This
Step 12 above.
(Not during running of the Cytospin).
(c)
Running
may be done
either before
or after.operation
a Program From Memory
Program Number 1
Operation
1
2
3
4
W
Press
Press
Press
Press
‘LOAD’
Program ‘1’
‘ENTER’
‘START’
Program Number 1 has now been
(d)
Viewing
Previously
Entered
Program
Display
Speed
Display
Time
Display
0
1
1
1
- previous
1500
1500
0
program
5
5
5
recalled
Program(s)
from memory and initiated
Accel
Display
entered LOW
LOW
LOW
or run.
‘.
The operator
having stored several
programs in memory (up to 9) may wish to later
view these
previously
entered programs to inspect
speed/time/accel
parameters
to act as a reminder in selecting
the desired
one.
Let us assume that Section
2 (a) and (b) have been followed
entering
and that the desired
parameters are speed: 800 rpm, time: 8 minutes,
program number cannot be immediately
remembered by the operator.
9 different
programs in memory,
accel: med, but the actual
Operation
1
2
3
Press
Press
Press
‘LOAD’
Program
Program
‘1’
$2’
Program
Display
Speed
Display
Time
Display
Accel
Display
0
1
2
0
0
5
8
HIGH
LOW
MED
1500
800
As you can see in this example, having sequenced
through the above steps,
Program Number 2 contains
the desired
operational
parameters
(speed/time/accel)
and can now, if desired,
be run.
Simply
follow
operational
section
2 (c) 3 through 4.
GUIDANCENOTES
1
To Repeat
a Particular
The operator
2
Program
has the choice
of
either,
(a>
storing
a program in memory for future use and subsequently
as detailed
in section
2 (b) and (c) or
(b)
simply closing
the lid following
the previous
run (with new samples correctly
pressing
‘START’ - as detailed
in Section
2 (a) steps 12 - 17 inclusive.
To Alter
a Program Mode Parameter
(a)
Press ‘CANCEL’ after
memory.
Please note
(b)
Alternatively
pressing
time/speed
parameter,
Pressing
previous
(by
using
‘SET TIME’ or
it is essential
the
running
this
program
from memory,
loaded)
‘CANCEL’ button)
‘SET SPEED’ to cancel
time or speed previously
entered
to then select
alternative
speed/time
parameter(s).
‘CANCEL’ systematically
after
having selected
the ‘ENTER’ button
will revert
both the speed and time displays
to zero.
the ‘CANCEL’ button again will
program parameters entered.
and
cause
the speed/time/accel
displays
to revert
back
into
for
to the
a
3
If
Program Number 1 is
required
but
Operation
not
closed
correctly:
Speed
Display
Time
Display
Accel
Display
Audible
Signal
Lid
Lock
Alarm
LED Display
Lid Lock
Illuminated
Lid Lock No Longer
Illuminated
Lid Lock No Longer
Illuminated
1
Press
'START'
1500
5
LOW
-
2
Close
Lid
1500
5
LOW
-
Unlocked
& Open
Unlocked
3
Press
'START'
0
5
LOW
-
Locked
From this
4
the Lid is
point
follow
If Program Number 1 is
balance
steps
12 - 17 in Section
required
but
2 (a).
the centrifuge
head has been loaded
Operation
Speed
Display
Time
Display
Accel
Display
1
2
3
1500
0
0
5
5
5
O-1500
o-1500*
4
Close lid
Press 'START'
Acceleration
Period
BALANCE' detected
Deceleration
Period
5
Head Stops
6
7
8
9
10
11
Switch 'OFF'
Switch ‘ONI
Re-select
Program 1
Correct
'OUT OF BALANCE'
Press 'START'
Follow Section
2 (a) step 12 on.
'OUT OF
Rotating
0
1500
1500
0
incorrectly
Audible
Signal
Lid
Lock
LOW
LOW
LOW
Alarm
Unlocked
Locked
Locked
5
LOW
Alarm
Locked
0
LOW
Alarm
Locked
LOW
LOW
LOW
LOW
3 set
Unlocked
Unlocked
Unlocked
Unlocked
and is
out of
Alarm
LED Display
Balance
Illuminated
Balance
'Illuminated
Balance
Illuminated
5
Invalid
Soeeds
Lower Than 200 mm
The Cytospin
3 sample chamber assembly will not 'TILT' into the upright
position
200 rpm is achieved.
The program memory will reject
as INVALID any speed lower
illustrated
in this example when 190 rpm is entered.
1
2
3
4
5
6
7
8
Press
Press
Press
Press
Press
Press
Press
Press
Action
6
'SET TIME'
‘5'
'ENTER'
'SET SPEED'
'1'
'9'
‘0'
'ENTER'
to be taken
Invalid
Speeds
The Cytospin
illustration,
0
0
0
0
1
19
190
0
i select
Higher
and enter
3 program memory will
examine the following
As Number 5 above
Press ‘2'
Press ‘0'
Press ‘1'
Press ‘0'
Press 'ENTER'
Action
to be taken
a value
of
Accel
Display
Audible
Signal
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
valid
valid
valid
valid
valid
valid
valid
invalid
key tone
key tone
key tone
key tone
key tone
key tone
key tone
speed
200 rpm or higher.
Than 2000 rpm
reject
any speed entered greater
than 2000 rpm.
procedures
when 2010 rpm is programmed.
Operation
1
2
3
4
5
6
Time
Display
Speed
Display
Operation
unless a speed of
than 200 rpmr as
Steps
- select
l-4
and enter
Speed
Display
Time
Display
Accel
Display
Audible
Signal
0
2
20
201
2010
0
5
5
5
5
5
5
HIGH
HIGH
HIGH
HIGH
HIGH
HIGH
valid
valid
valid
valid
valid
invalid
a value
of
2000 rpm or lower.
As an
key tone
key tone
key tone
key tone
key tone
speed
7
Invalid
Speed/Time
Parameters
The Cytospin
3 will not start without a valid
speed and time entered
program cannot be saved if the speed and time are not valid.
8
‘!’
Light
(Overspeed
Indication/Rotor
and displayed.
control
becomes
irregular
during
Similarly
should the sealed head assembly fail
to start rotating
due to mechanical
malfunction,
then the ‘!I light
will be illuminated
after
approximately
3 seconds.
signal
will sound, and the ‘drive’
to the sealed head motor will be disconnected.
and then refer
a
a run,
due to
Jam)
The ‘! ’ light
is illuminated
in the event that speed
electrical
interference
or instrument
malfunction.
Turn the power off,
Similarly
to Section
2, No 4,
Steps
7,
8,
10,
11.
or electrical
An audible
alarm
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SWVICEABILITYTEST
Introduction
This procedure
describes
the test which can be carried
out, at
any time, on the Cytospin
3, to ascertain
if the machine is
functioning
correctly.
In the following
tests a sealed head is
fitted
without
cell
or cell
holders.
Instruments
Required
One Multimeter,
Insulation
one 1OOOV Megger,
one Stopwatch.
Tests
Before
applying
power to the machine the following
insulation
tests must be carried
out.
Using the multimeter,
check the
resistance
path between the earth wire and any metal parts of the
machine,
this resistance
is to be less than ORl.
Connect the
1OOOV megger between the live
and neutral
wires on the mains
power lead.
With the power switch in the off position,
the
resistance
should be greater
than 100 megohms.
Short the live
and neutral
wires of the mains power lead together.
With the
power switch in the ON position
the resistance
between the
live/neutral
wires and the earth should be greater
than 25
If above is correct,
apply power to machine.
megohms.
Procedure
When power is applied
to the Cytospin
3 thejdisplay
panel should
initialise
to the following
(if not, consult
Fault Diagnosis
Section
and/or Principles
of Operation)
and the alarm should
sound for three seconds.
Program Display
Speed Display
Time Display
HIGH
MED
LOW
STOP
START
BAL
!
LID LOCK
OPEN LID
0
0
0
ON
OFF
OFF
ON
OFF
OFF
OFF
OFF
OFF
Keyboard Tests
Press
SET SPEED, check
speed
0 flashes.
Press
appears on the right
0 - 9 in turn and check that digit
hand side of the speed display
and "rolls
round".
Press
CANCEL, check
that
display
reads
0 flashing.
Press
CANCEL, check
that
display
reads
0.
8
HOME
Press
SET TIME, check
that
display
Press
0 - 9 in turn and check that digit
appears
side of time display
and "rolls
round".
Press
CANCEL, check
that
display
reads
0 flashing.
Press
CANCEL, check
that
display
reads
0.
Press
LOAD, check
Press
0 - 9 in turn and check
program window.
Press
CANCEL, check
program
0 flashes.
Press
CANCEL, check
program
displays
program
reads
0 flashing.
on right-hand
0 flashes.
that
the digit
appears
in the
0.
Operation Tests
Press
SET SPEED.
Press
2000.
Press
ENTER, display
Press
SET TIME.
Press
10.
Press
ENTER, display
Press
START.
should
read
2000.
should
read
10.
The Start LED should now come on and the Stop LED go off.
The
sealed head will begin to rotate
and accelerate
quickly
until
the
SET SPEED is reached.
The speed display
will now read the actuaZ
speed of the sealed head in rpm and time display
will begin to
count down towards 0.
When the time display
reaches 0 the sealed head will come to a
The Start LED will go off and the Stop LED will come on.
halt.
The speed display
will now read the SET SPEED (ie 2000) and the
time display
will reset
from 0 to 10.
The audible alarm will
sound at the end of operation.
Press
SET SPEED.
Press
200.
Press
ENTER, display
will
now read
200.
HOME
Remove the cells
the sealed head
and cell holders
from the sealed
in the machine and close
the lid.
Press
SET TIME.
Press
30.
Press
ENTER, the display
Press
HIGH ACCEL, the HIGH ACCEL LED should
ACCEL LED should go off.
Press
START, the sealed
should
read
head should
head,
replace
30.
begin
come on and the LOW
to rotate.
check that the timer counts down in 1 minute
Using the stopwatch,
Check that the speed display
remains at 2000 rpm and
intervals.
that the head remains quiet throughout
the 30 minute program.
When the timer reaches 0 the machine should
The time display
should reset
alarm sound.
stop and the audible
to 30.
If the Cytospin
3 passes the above functional
tests it can be
If the machine fails
to pass any
considered
to be serviceable.
of the tests
then reference
must be made to the appropriate
part
of the servicing
manual.
10
HOME
DAILY AND WEEKLYMAINTENANCE
CLEANINGAND STERILISING THE CYTOSPIN 3
All the components of the Cytospin
3 which are likely
to become
contaminated
have been designed
to be easily
cleaned using mild
detergent
solutions,
and then sterilised
using a wide variety
of
agents.
In the interest
of laboratory
safety,
Shandon recommends
suggested
sterilisation
procedures
are adhered to.
All the components of the sealed head, the
safety
cover and front panel, are designed
that
centrifuge
bowl liner,
to be easily
cleaned.
Each component part is dealt with individually
and if the
instructions
are followed,
no damage will occur.
This is
particularly
important , since any chemical attack on the
components of the sealed head or hinged safety
cover will weaken
<;-iz -p:?rial
and create a serious
hazard.
When handling,
cleaning
or sterilising
any component,
it is
advisable
to wear gloves
as they offer
protection
against
infection
and chemical
effects
on the skin due to the detergent
After cleaning
and sterilising
and/or disinfectants
being used.
it should be examined for damage.
any component,
If in doubt as
it should not be used on the centrifuge
until
to its state,
inspected
by your Safety Officer.
IMPORTANTNOTE
If you are in doubt as to the type of disinfectant
you
many brands do not declare
the nature of the
are using,
, check with the manufacturer
before
active
ingredients
using the solution
with any component part of the
Cytospin
3.
HYPOCHLORITEbased disinfectants
should
sterilise
centrifuges
of any type.
NEVER be used
to
FRONT PANEL
Frequency:
Weekly and after
Clean :
Use a damp cloth
to clean panel;
do not use abrasive
powders,
these will damage the surface
of the panel.
Sterilise:
Use 2% glutaraldehyde
prepared
facturer’s
instructions.
Notes:
any spillage.
a)
Never clean the front
similar
solvents.
b)
The front panel
liquid
or spray
panel
according
with
Xylene,
can be polished
if
furniture
polish.
11
to manuToluene
required
with
or
a
HOME
HINGED SAFETY COVER
Frequency:
Daily
and after
any serious
spillage.
Clean:
Use warm soapy water, DO NOT use abrasive
powders,
will scratch
the surface
and make it more difficult
clean and also create
a potential
source of crosscontamination.
Sterilise:
Use 2% glutaraldehyde
turer's
instructions.
Note:
DO NOT clean the hinged
could weaken the safety
prepared
cover
cover.
according
with
these
to
to manufac-
any solvents
-
these
BOWLLINER
Frequency:
Daily
and after
any serious
spillage.
Clean:
Use warm soapy water,
will create
scratches
and make sterilisation
do not use abrasive
powders,
they
which may harbour micro-organiss
difficult.
Sterilise:
Use 2% glutaraldehyde
turer's
instructions.
prepared
according
to manufac-
SEALED HEAD ASSEMBLY
Frequency:
Daily
and immediately
after
any-serious
spillage.
Sterilise:
The head assembly can be sterilised
as a whole unit b
autoclaving
at 121OC (250'F)
for 15 minutes.
It is
necessary
to unlock the lid so that the pressure
ins&&z
the head will be equalised
with those in the autoclave
and to allow the free entry of steam into the interior
of the head.
Clean:
After sterilisation
of the whole head, all components
should be removed, washed in warm soapy water and dri&
in an oven.
(Maximum temperature
65'C or 149'F)
befon
re-assembly.
SEALED HEAD BASE
Frequency:
Daily
and immediately
Sterilise:
Autoclave
at 121OC (250OF) for 15 minutes.
Wipe with2%
glutaraldehyde
or a phenolic
disinfectant
prepared
according
to manufacturer's
instructions.
Clean:_
After sterilisation
clean using warm soapy water, riiae
DO NOT USE hard brushes to
in clean water and dry.
clean this component.
12
after
any serious
spillage.
HOME
SEALED HEAD SLIDE CLIP ASSEMBLYSUPPORTPLATE
Frequency:
Daily.
Sterilise:
As Sealed
Head - Base.
Clean:
As Sealed
Head - Base.
Note:
This component is easily
removed from the Sealed Head
Base by removing two thumb screws.
This enables
the
under surface
of the support plate to be cleaned easily
and also facilitates
cleaning
of the inside
surface
of
the sealed head base.
The support plate can be totally
immersed in 2% glutaraldehyde
disinfectant
if required-
SEALED HEAD LID
Frequency:
Daily.
Sterilise:
As Sealed
Head - Base.
Clean:
As Sealed
Head - Base.
Note:
The silicone
rubber seal around the rim of the lid cau
be easily
removed and replaced.
It is advisable
to
remove this seal at weekly intervals
to enable all the
surface
of the lid to be cleaned.
A new seal should Be
fitted
at intervals
of 12 months.
CYTOCLIP
Frequency:
Daily.
Sterilise:
Autoclave
at 121OC (250'F)
2% glutaraldehyde
solution
instructions.
Clean:
Rinse
Note:
It is advisable
to ensure that the pressure
spring is
unlocked,
releasing
any pressure
from the-spring
durQg
It is also important
to ensure that ube
sterilisation.
face of the slide
clip is clean as any raised
particles
could cause microscope
slides
to break under the appl&ed
'gr force.
in clean
water
SAMPLECHAMBER
Frequency:
After
use.
13
before
for 15 minutes or immerse in
according
to manufacturer's
use and hot
air
dry.
HOME
5
SAFETY
1)
2)
6
There are potentially
lethal
voltages
in the Cytospin 3.
all necessary
precautions
when working on live machines.
Beware of mechanically
tedly under the control
Take
moving parts.
They may move unexpecof the microcomputer
system.
STATIC DAHAGETO HOS DEVICES
Some of
devices
the components used on the Cytospin
and are sensitive
to static
damage.
1)
Take all
2)
Treat
3
all
Remember,
to fail.
necessary
precautions
unknown devices
statically
3 electronics
are MOS
when handling.
as MOS.
damaged devices
may take weeks or months
DO NOT TAKE CHANCES
1.4
HOME
7
FAULT DIAGNOSIS AND REPAIR
If the Cytospin
3 stops working it will be because either
a fault
condition
has occurred
or a safety
circuit
has operated.
Refer
to the list
of fault
conditions
below until you find the symptoms
Turn to the relevant
page and work through the
of your fault.
methods of diagnosis
and solutions.
To retest
possible
causes,
the Cytospin
after
each repair
or replacement,
follow
the
serviceability
test.
If the symptom of your
principles
of operation
Fault
fault
is not listed
below
and the relevant
circuit
refer
to
diagram.
Page
Condition
Panel
LED's not
16
1
Front
2
SPEED, TIME, PROG, ACCEL and STOP display
will not initialise
on 'Power On'.
3
STOP, START, HIGH and LOW ACCEL LED's will
initialise
on 'Power On'.
Cytospin
3 will
Lid lock
LED lights,
Motor will
Balance
the
not
not
illuminated
accept
program
when Start
LED's
18
not
19
commands.
button
pressed.
21
23
run.
24
LED lights.
Balance LED fails
sealed head).
20
to light
9
! LED lights
speed control
and motor
loop).
10
Lid solenoid
not
stops
(with
out-of-balance
(failure
of
motor
26
27
28
working.
THERE ARE POTENTIALLY LETHAL VOLTAGESIN THE MACHINESO CARE MUSTBE
TAKEN WHENTESTING OR MAKINGADJUSTMENTSON LIVE MACHINES.
15
FAULT CONDITION 1: FRONT PANEL LED’S NOT ILLUMINATED
Possible
Cause
1.1
Mains supply
1.2
Incorrect
supply
has failed.
mains power
l
1.3
Plug and fuse
intact.
FSl not
1.4
Faulty
wiring.
switch
cable,
or
Diagnosis
Solution
Check mains supply with suitable
meter or by examining another
appliance.
Wait for supply to return or
an alternative
power source.
Retest.
Check that supply for 240V Cytospin
is between 220V and 25OV, for 1lOV
machine between 1OOV and 120V.
If not, connect
to correct
supply
and retest
using serviceability
test.
Check plug.
Check that fuse FSl is
in place and intact
(Drawing
E740-l-l),
0.8 amp for 24OV,
2 amp for 1lOV.
If not, fix properly
or replace.
Retest.
If fuse blows again,
investigate
short circuits,
earth
(ground)
leakage etc.
(a)
Check there is mains input
voltage
at the input terminals
of SW1 (Drawing E740-l-l).
If not,
wiring.
Retest.
inspect
the cable and
Replace as necessary.
(b)
Ensure SW1 is closed
and check
if mains input voltage
is present
at output side of SW1 (Drawing
E740-l-l).
If
replace
not,
SWl.
Retest.
find
FAULT CONDITION 1:
Possible
1.5
FRONT PANEL LED'S NOT ILLUMINATED
Cause
Power supply from
transformer
plate.
Diagnosis
Solution
Check at socket
nominal voltages
(a) AC Voltages
Between
Between
Between
Between
(b)
pins
pins
pins
pins
DC Voltages
Between pins
Between pins
for the following
(Drawing E740-l-l)
1 and 2:
5 and 6:
10 and 12:
11 and 12:
24V
15V
8V
8V
AC
AC
AC
AC
7 and 8:
9 and 8:
24V DC
24V DC
(a)
If not, test transformer
windings for continuity
(Drawing
E740-l-1).
Typical
resistances
for windings are:
Primary
16.0 R
Secondary 24V
0.4 R
Secondary 15V
1.4 R
Secondary 8-0-8V
0.5 9
(b)
If not, check across
bridge
rectifier
Bl for 24V DC and 24V
AC (Drawing E740-l-l).
If correct,
inspect
and test
associated
plugs and'wiring
for
open or short circuits,
earth
(ground)
leakage etc (Drawing
E740-1-1).
Replace as necessary.
Retest.
FAULT CONDITION 2:
Possible
SPEED, TIME, PROG, ACCEL AND STOP DISPLAY LED'S WILL NOT INITIALISE ON 'POWER ON'
Cause
Diagnosis
Solution
2.1
Incorrect
power supplies
to mains PCB.
Check that 12V, 5V, -5V and OV DC
rails
are available
on Main PCB.
If not, check through relevant
supply circuit
and replace
as
necessary
(Drawing F740-1-2,
E740-l-l).
Retest.
2.2
Mains PCB faulty.
Check main PCB by replacing
with
serviceable
PCB. Before replacing
PCB check that the correct
voltages
(Drawing E740-l-l)
are available.
(Refer
to voltage
table,
Principles
of Operation).
If correct,
place.
leave
new PCB in
FAULT CONDITION 3:
Possible
STOP, START, HIGH AND LOWACCEL LED’S WILL NOT INITIALISE
Cause
3.1
Fault
on main PCB.
3.2
LED’s not
3.3
Wiring
fault.
functioning.
or connection
ON ‘POWER ON’
Diagnosis
Solution
Check main PCB power supplies
(voltage
table,
Principles
of
Operation).
If correct,
replace
main PCB with serviceable
main
PCB (after
checking
voltages).
If correct,
place.
Press the Act switch and check
that the Lo Act LED lights.
Program the Cytospin
and press
the Start switch,
check that the
start LEd lights
and that the
Cytospin
operates
correctly.
If correct,
test the LED’s which
are not functioning.
Replace as
necessary.
Retest.
Check associated
wiring and
connectors
for continuity,
open
or short circuits,
earth (ground)
leakages
(Drawing F740-1-2,
E740-l-l).
If not,
Retest.
leave
replace
new PCB in
as necessary.
FAULT CONDITION 4:
Possible
CYTOSPIN 3 WILL NOT ACCEPT PROGRAMCOMMANDS
Cause
Diagnosis
Solution
4.1
Main PCB.
Replace PCB with serviceable
PCB check
PCB. Before replacing
that supply voltages
are correct
(voltage
table,
Principles
of
Operation).
If now correct,
place.
leave
4.2
Fault on Cytospin
3
keyboard (front
panel).
Check keyboard by fitting
front
panel to serviceable
Cytospin.
If.not,
Retest.
replace
as necessary.
4.3
Fault on molex
connections
between
main PCB and keyboard
Check connectors
Replace
as necessary.
and wiring.
new PCB in
Retest.
FAULT CONDITION 5:
Possible
LID LOCK LED LIGHTS WHENSTART BUTTONPRESSED
Solution
Diagnosis
Cause
5.1
Lid not
closed
5.2
Lid lock
faulty.
5.3
Magnetic proximity
(SW3) faulty.
switch
properly.
(SW5)
switch
Check lid
fully
closed.
If
correct,
retest.
Check operation
of SW5 as follows:
With the lid fully
closed,
connect
a continuity
tester
between pins 11
and 12 of socket 3 (Drawing E740-1-1)
and check for continuity.
Manually
operate
the solenoid
(Sol 1) until
the lid catch opens and the lid
raises
slightly
(you should be able
to hear the catch opening).
There
should now be an open circuit
between
pin 11 and 12 of socket 3.
If not,
Retest.
replace
SW5 as necessary.
Check the operation
of SW3 as
follows:
Place a magnet on the top trim in
such a position
that it will close
the proximity
switch.
Connect a
continuity
tester
between pin 7 on
PL2B and pin 11, PL4A (Drawing
E740-1-1)
continuity.
Remove magnet
and check that there is now an open
circuit
between these pins.
If not,
Retest.
replace
SW3 as necessary.
If correct,
operate
Cytospin with
external
magnet in position.
If
machine now functions
correctly
(ie defect
not apparent)
this
indicates
that lid magnet is not
closing
proximity
switch.
FAULT CONDITION 5:
Possible
lo
N
LID LOCK LED LIGHTS WHENSTART BUTTONPRESSED
Cause
5.4
Fault on lid
wiring.
lock
5.5
Main PCB fault.
circuit
Diagnosis
Solution
Check associated
wiring
(Drawing E740-l-l).
Replace
Replace main PCB with serviceable
PCB. Before replacing
PCB check
that correct
voltages
are
available
(voltage
table,
Principles
of Operation).
If
as necessary.
correct,
leave
new PCB in place.
FAULT CONDITION 6:
Possible
MOTORWILL NOT RUN
6.1
Motor
6.2
Incorrect
to motor.
6.3
Fault
6.4
Transistor
6.5
Main PCB
Solution
Diagnosis
Cause
If not,
Retest.
replace
motor
Check power supply circuits
and
components (Drawing E740-1-1).
If not,
Retest.
replace
as necessary.
Check Relay A for correct
(Drawing E740-1-1).
If not?
Retest.
replace
as necessary.
Check transistor
TRl for correct
operation
(Drawing E740-l-l).
If not,
Retest.
replace
as necessary.
Replace main PCB with serviceable
PCB. Before replacing
PCB check
that correct
voltages
are available
(voltage
table,
Principles
of
Operation).
If
Check coil
of motor
(Drawing E740-l-l).
fault.
power supplies
on Relay
A.
(TRl)
fault.
for
continuity
operation
correct,
leave
as necessary.
new PCB in place.
FAULT CONDITION 7: BALANCELED LIGHTS
Possible
solution
Diagnosis
Cause
If
correct,
retest.
Adjust vibration
switch (refer
to
adjustment
procedure
Testing
and
Calibration
section).
If
correct,
retest.
Check operation
of SW4 as follows:
Using a continuity
tester,
test for
open circuit
between pins 10 and 12,
socket 3 (Drawing E740-1-1).
With
tester
still
connected
physically,
tilt
the Cytospin
to the side in
order to close
SW4. Viewing the
Cytospin
from the front,
SW4 is
positioned
laterally
at the rear of
the machine.
If not,
Retest.
7.1
Sealed head loaded
incorrectly.
Check that
correctly.
7.2
Vibration
incorrectly
switch (SW4)
adjusted.
7.3
Vibration
faulty.
switch
(SW4)
sealed
head is
loaded
replace
SW4 as necessary.
FAULT CONDITION 7:
Possible
7.4
Cause
Main PCB Fault
BALANCELED LIGHTS
Diagnosis
Solution
Check main PCB by replacing
with
serviceable
PCB. Before replacing
PCB check that correct
voltages
are
available
(voltage
table,
Principles
of Operation).
If
correct,
leave
new PCB in place.
FAULT CONDITION 8:
Possible
BALANCELED FAILS TO LIGHT (with
Cause
sealed
head out
of
balance)
Diagnosis
Solution
8.1
Vibration
incorrectly
switch
(SW4)
adjusted.
Adjust vibration
switch (refer
to
adjustment
procedure
Testing
and
Calibration
section).
If
8.2
Vibration
associated
switch (SW4) or
wiring
faulty.
Check switch and wiring (refer
Drawing E740-l-l
and Fault
Diagnosis,
paragraph 8.3).
If not,
Retest.
replace
as necessary.
8.3
Faulty
If not,
Retest.
replace
as necessary.
8.4
Main PCB fault.
LED.
Test LED using diode
(Drawing E740-1-2).
to
tester
Check main PCB by replacing
PCB
with serviceable
PCB. Before
replacing
PCB check that correct
voltages
are available
(voltage
table,
Principles
of Operation).
If
correct,
correct,
retest.
leave
new PCB in place.
FAULT CONDITION 9:
Possible
N
-4
! LED LIGHTS AND MOTORSTOPS (failure
Cause
9.1
Fault on control
sys tern.
9.2
Main PCB fault.
opto
of
motor
speed
control
loop)
Diagnosis
Solution
With ‘Power On’ (but start switch
not pressed)
connect
voltmeter
between pins 1 and 2 on sensor PCB
plug (Drawing E74@-1-1).
Slowly
turn the sealed head assembly
(or drive boss) by hand and check
that the output from the opto is
present.
If not, check
disc encoder,
as necessary.
Check main PCB by replacing
with
serviceable
PCB. Before replacing
PCB check that correct
voltages
are available
(voltage
table,
Principles
of Operation).
If
correct,
opto transistor,
wiring etc.
Replace
Retest.
leave
new PCB in place.
FAULT CONDITION 10:
Possible
10.1
LID SOLENOIDWILL NOT OPERATE
Cause
Fault on transistor
T12
and T13 (main PCB).
Diagnosis
Solution
With solenoid
button pressed check
output of T12 and pin 1 PL2B main PCB
(Drawing F740-1-2).
(a)
check solenoid
and
If correct,
Replace as
catch assembly.
necessary.
Retest.
(b)
If not, check transistor
T12 and
T13, microswitch
and wiring.
Replace as necessary.
Retest.
HOME
8
FIT'UXG, TESTING AND CBLIBRATION
All
internal
screws
and nuts
to be fixed
with
Loctite
Screwlok,
THE EXCEPTION OF ANY IN CONTACT WITH PLASTICS, where Araldite
lid)
must be used.
(1)
MOTORREMOVALAND REPLACEMENT
WITH
(eg
a>
With the access door open and the sealed head removed,
isolate
the machine from the electrical
supply.
b)
Loosen the M3 grub screw in the side of the taper,
pull the
drive taper off the motor shaft.
Remove “V” ring seal from
Do not lose the key in the motor shaft,
the motor shaft.
it should be kept for fitting
into the new motor shaft.
c>
Remove the four countersunk
screws securing
the steel
fixing
plate
to the bowl and motor.
The bowl is now
released
from the motor.
(Retain
these special
screws
refitting
new motor).
for
d)
Remove the outer two countersunk
screws securing
the front
of the bowl to the instrument
case.
(These screws are
under the silicone
rubber seal behind the nosecone
trim;
care should be taken not to damage the seal).
e>
Close
foam,
f>
Remove the four screws securing
the nosecone
to the plinth
(base)
and carefully
pull the nosecone away from the case.
The nosecone will
fit
face down in front of the plinth
(place
some protection
on the bench for the control
panel).
Disengage
the three connectors , remove the M5 earth nut and
The nosecone
can now be taken from the machine.
leads.
g)
Turn the machine upside down and remove the six securing
screws from the plinth
(base).
The plinth
can now be
tilted
up and to one side for removal of the M5 earth nut
and leads (up and to the left when the machine is upside
The plinth
can now be removed.
down and facing
front).
h)
Loosen the two screws securing
the encoder bracket
to the
guard barrier
and slide
the bracket back as far as
Release
the M2.5 grub
retighten
the screws.
possible,
screw fixing
the encoder disc to the motor shaft and
carefully
pull the disc off the shaft,
after
removing the
grip ring from the motor shaft.
i>
Remove the nut retaining
barrier.
j)
Remove the four countersunk
screws that fix the motor
the motor will now be free
housing to the guard barrier,
remove from the guard barrier
once the leads have been
(When fitting
the new motor ensure correct
desoldered.
wiring of motor leads).
and secure the access
should be placed over
29
door.
(A protecting
the door).
the motor
leads
cover,
ie
to the guard
to
HOME
k)
The motor is now removed and the motor housing released
from the motor by removal of the four countersunk
screws.
Fitting
the new motor is
but the following
points
generally
the reverse
should be noted:
of
the removal,
a)
It is important
to use the original
screwlok
screws in and
LOCTITR SEX1 LOCK HUST NOT COKR INTO
around the motor.
CONTACTWITH ANY PLASTIC OR PAINTED COXPONENT.
b)
When re-fitting
the encoder disc and bracket,
the disc
should turn freely
near the centre
of the gap between the
should be fixed so that the
encoder heads, and the bracket
encoder assembly is as close as possible
to the edge of the
disc without any risk of contact
between the two.
Refit
the grip ring to the motor shaft.
c)
When re-fitting
screws.
the plinth
(base).do
The machine is turned upright
(manually operate
the solenoid
not
tighten
the six
and the access
door opened
to release
the catch).
Replace
the PTFE seal along the top edge of the nosecone.
Care must be taken when re-fi t ting the nosecone
that the
two lugs fit smoothly under the bowl seal.
Loosely
fit the
two countersunk
screws..
Fit the nosecone
so that the front
lower edge of the nosecone
lines
up with the front
top edge
Fix the nosecone
using the four
of the plinth
(base).
Do not over-tighten
the two countersunk
screws in
screws.
Pull the case forward to meet the nosecone
and
the bowl.
tighten
the six screws..
d)
Fit the “V” ring seal to the motor shaft with the lip
Push the seal just past the keyway in the
facing
down.
Fit the key into the keyway on the motor shaft.
shaft.
The drive taper is then fitted
and fixed 1 mm from the
steel
fixing
plate
(the seal will be pushed down into
position
by the drive taper).
Reconnect
the electrical
instrument.
(2)
supply
and test
the
functions
of
the
LID REMOVALAND REPLACEMENT
a)
Before isolating
open the lid.
the machine
b)
Remove the right hand screw (looking
from the front of the
machine) fastening
the lid hinge to the pivot
(do not lose
Remove the
the spacing washer or the shakeproof
washer).
two M3 countersunk
socket screws holding
the right hand
hinge plate to the lid frame and remove the hinge plate.
(Support
the lid while removing these parts).
30
from
the electrical
supply
HOME
(3)
c)
The lid can now be moved to the left
and the left-hand
pivot will slide
out of the bearing block.
The lid can WV
be dismantled.
d)
Replacing
e)
Forward adjustment
of the lid is achieved
by slackening
the
two hinge pivot screws and sliding
the lid forward or back.
f)
To raise or lower the lid loosen
the four screws securing
the two bearing
blocks at the rear of the machine (two
either
side)
and adjust
the lid height accordingly.
Remember to also adjust
the plunger height in order to keep
the lid on the seal correctly.
the lid
is
the reverse
of
the removal.
DRIP TRAY AND LID SEAL REMOVALAND REPLACEMENT
a)
Before isolating
open the lid.
the machine
from the electrical
supply
b)
Remove the seventeen
countersunk
and the drip tray to the case of
c)
Remove the drive
taper from the motor shaft (M3 grub
retain
the key from the motor shaft.
Remove the ‘V’
seal from the motor shaft.
d)
Remove the four countersunk
remove the plate.
The drip
e)
Inspect
the rubber extrusion
on the lid of the guard
barrier
and replace
if necessary.
When removing only the
lid seal,
the seventeen
screws need to be removed and a sew
seal can be fitted
around the drip tray, ensure that the
lower lip of the seal fits
over the case of the machine and
that the seal sits properly
on the drip tray.
screws retaining
the machine.
the seal
screw)
ring
screws in the clamp plate
tray can now be removed.
and
Replacement
of the drip tray is the reverse of the removal.
The motor shaft
‘V’ ring seal must be fit.ted with the lip
facing
down, push the seal just past the keyway in the
shaft.
Fit the key into the keyway on the motor shaft,
the
drive taper is then fitted
1 mm from the steel
clamp plate
(the seal will be pushed down into position
by the drive
taper).
Secure the drive taper.
(4)
LID DAMPERADJUSTMENT
a)
Remove the drip
tray
b)
The damper is
case.
c)
To increase
damping , screw
damper body.
found
as described
on the right
31
in Section
hand side
the nylon
3.
of
adjuster
the main
into
the
HOME
d)
(5)
(6)
i
To remove the damper from the machine,
remove
right hand hinge screw fixing
the hinge plate
pivot.
ii
Remove the two M5 nuts securing
the damper body
case.
The damper assembly can then be removed.
iii
The link arm is separated
on the damper arm.
by removal
of
the
to the
to the
the retainer
GUARDBARRIER REMOVALAND REPLACEMENT
a)
Refer
to section
(l),
b)
After closing
and protecting
the lid,
turn the machine
upside down and remove the ten (10) M4 screws securing
the
plinth
(base)
to the case and nosecone.
The plinth
will
then lift
off to one side of the machine.
c)
Remove the M5 earth nuts, leads and plugs
plinth
to the case and remove the plinth.
d)
Disconnect
the wiring
balance switch.
e)
Remove the eight springs
supporting
the guard barrier
(loop
a piece of cable through the outer loop of the spring,
restrain
the machine with one hand and pull the spring free
with the other).
f)
The guard
g)
Replacement
barrier
is
step
to
a and step
the motor,
c.
joining
optics
and out
the
of
can now be removed.
the reverse
of
the removal.
LID CATCHMECHANISM
a)
If the whole assembly is to be removed,
the guard
has to be removed first
(see section
(5))
b)
Once the guard barrier
is extracted,
remove
screws securing
the aluminium angle carrying
The assembly can now be inspected.
assembly.
c)
the microswitch
and the solenoid
can be
The catch assembly,
removed without removing the aluminium angle but care must
be taken when refitting
that the components are correctly
fitted.
d)
In order to function
correctly
the solenoid
plunger must
always be fully
home when the solenoid
is energised,
also
the catch must clear
the lid plunger with sufficient
clearance
(until
it is flush with the side of the lid
Once the solenoid
is fully
home and the
plunger hole).
catch is flush with the hole sides,
the catch must then be
free to move 0.5 to 1.0 mm further
out.
32
barrier
the four (4)
the catch
M3
HOME
(7)
OUT OF BALANCESWITCH ADJUSTMENT
a)
Remove the round access
instrument.
b)
The out of
hole.
cl
the switch is mounted on a rectangular
screws.
Loosen both of these screws.
d)
One of the screws is in a slot.
plate counter-clockwise
a small
Retighten
both screws.
balance
plug
switch
on the back of
can be seen
the
through
plate
this
held
access
by two
Slide the rectangular
amount - approximately
loo.
e)
Test for out of balance using all 12 chambers and clip
assemblies.
Once you are satisfied
the machine does not go
out of balance,
proceed
to step f).
f)
Using 10 chambers and clip assemblies,
load the sealed
head (see Operator Manual).
Ensure that the two positions
left
vacant are not directly
opposite
each other.
Select
high acceleration
and 2000 rpm and start
machine.
The out of balance should operate
at a point between 1000
and 1500 rpm.
Repeat
g)
(8)
using
Make certain
and retest.
low acceleration.
the screws
are
tight;
replace
the access
plug
POWERSUPPLY REMOVALAND REPLACEMENT
a)
Isolate
machine
from
the electrical
b)
Protect
the lid
(use
foam etc).
c)
Turn the machine
screws.
d)
Lift
the plinth
up and to the left
side (looking
Disconnect
the 3 plugs and ground leads,
front).
plinth
is then free to remove.
e)
Disconnect
the
supporting
the
fixing
screws
supply is now
f)
Replacement
is
upside
supply.
down and remove
the
ten
(10)
M4
from the
and the
electrical
leads from the power supply,
and
plinth
and power supply,
remove the four
from the underside
of the plinth.
The power
free of the plinth.
the reverse
33
of
the removal
instructions.
HOME
(9)
HEATSINK
Two different
a)
b)
Internal
External
a)
Internal
ii)
heatsink
may be found
External
Remove the two outer M3 screws
heatsink
from the machine.
i>
(10)
of
Remove the plinth
[as in Section
8, paragraphs
a)
to d)].
Disconnect
and remove the heatsink
retaining
nuts,
desolder
the transistor
leads and disconnect
the
wiring
fixed
to the plinth.
The plinth
can now be
removed.
i>
b)
types
and extract
ii)
The transistor
mounting body is secured
screws.
Remove these and the transistor
Desolder
and remove from the machine.
iii)
In both
removal.
cases
the replacement
is
the
using two M3
can be seen.
the opposite
of
the
NOSECONEASSEMBLY
Removal
and Replacement
a)
Remove the nosecone,
and f).
b)
Disconnect
partially
Take care
c)
Disconnect
Main PCB
(see
Section
1,
paragraphs
a,
d
the main PCB from its retaining
pillars,
and
extract
it through the back of the nosecone.
not to damage any of the components on the board.
PCB plugs.
Remove the main PCB.
Replacement
NB:
is
Replace
Proximity
the reverse
the PTFE seal
of
removal.
along
the
top edge of
the nosecone.
Switch
a>
Remove the nosecone
b)
Remove the main PCB.
(Section
34
1, paragraphs
a,
d and f).
HOME
c>
Remove the two M4 screws
remove the trim.
d)
Remove the two M3 nuts
Note:
retaining
and remove
the nosecone
the proximity
trim and
switch.
It is possible
to remove the trim.without
removing the
main PCB using a screw retaining
screwdriver,
but great
care must be taken to avoid damage to any components on
the PCB.
Replacement
is the reverse
of removal,
but when positioning
the
proximity
switch it must be adjusted
so that the machine will
not start when the lid is slightly
open.
The switch must be
out of the magnetic field
before
the lid plunger releases
the
lid catch microswitch.
NB:
Replace
Front
the PTFE seal
along
top edge of
the nosecone.
Panel
a)
Remove the nosecone
b)
Remove the main PCB.
c)
Remove the eight
(8) M3 nuts and remove the front
from the front of the nosecone.
Replacement
NB:
Replace
replace
is
(Section
the reverse
the PTFE seal
the PTFE seal
of
1, paragraphs
a,
d and f).
panel
removal.
behind the front panel.
Also
along the top edge of the nosecone.
35
CYTOSPIN 3
PARTS LIST IDENTIFICATION
Ident
G,
4
No
Part
No
Description
Issue
MA 1000 07P
1
1
59930096
Top Cap Locking
2
59930097
Handle
3
PO7595
Seal
4
59930095
Locking
5
PO7437
Top Cover
6
59930094
Main Body - Locking
Device
5
7
PO9638
Ball
(2)
1
8
PO9698
Thumb Nuts (2)
1
9
59920047
Cell
Plate
3
10
PO7431
Seal
V Ring
1
11
59930093
Hub Sealed
- Sealed
- Silicone
Pin
From Ser No
Head Assembly
3
- Sealed
1
Pin - Locking
Head
Device
1
Mouldings
Bearing
%" dia
Head
5
4
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
From Ser No
Issue
MA 1000 07P
1
12
PO6007
Grub Screw M3 x 8 (2)
13
PO7525
0 Ring
1
14
PO7516
Seal
1
15
59920046
Inner
Bowl
1
16
59930063
Drive
Boss
4
17
PO7432
V Ring
- Motor Shaft
1
18
59930068
Fixing
Collar
4
19
PO7596
Moulded Seal
1
20
59920033
Drip Tray
2
21
PO7512
Key 2 mm x 2 mm x 12
1
22
PO7402
Motor
1
2;;:
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
From Ser No
Issue
MA 1000 07P
7
II
1
23
59920034
Outer
Bowl
24
PO9610
Spring
Retention
25
PO7441
Spring
Barrier
26
59920038
Bracket
27
59930072
Clamp Plate
28
PO7524
Mercury
Position
29
59930070
Support
Pillar
30
59930064
Support
Collar
31
59930059
Carrier
Plate
32
PO7444
Encoder
Disc
33
59930060
Clamp Plate
Pin (8)
(8)
- Vibration
Switch
11
1
11
2
11
Sensor
(3)
II
1
1
II
2
II
5
II
2
11
1
II
1
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
From Ser No
Issue
MA 1000 07P
i
II
1
34
PO7522
Grip
Ring
35
59920127
Mounting
36
PO7467
Opt0 Interrupter
(2)
1
36
59920131
Opto Interrupter
PCB
2
37
59930154
Angle
Bracket
Right
1
37
59930155
Angle
Bracket
Left
1
38
59910131
Motor Suppresser
39
PO6979
12 Way Receptacle
40
59930051
Mounting
41
PO4249
5 mm Nut
1
41
59930162
Locknut
3
Bracket
&
Block
Plate
Housing
2
1
1
PARTS LIST IDENTIFICATION
Ident
No
Part No
Description
From Ser No
Issue
42
59930161
Plunger
MA 1000 07P
2
43
74010051
Lid Panel
44
74030053
Screw - Hinge Plate
45
74030052
Hinge Plate
- Right
45
74030051
Hinge Plate
- Left
46
59930071
Tapping
47
59930055
Hinge Pivot
48
59930152
Hinge Block
48
59930167
Hinge Block
49
59920032
50
PO7430
Lid Catch
Assembly
11
1
(2)
II
1
Hand
II
1
II
1
11
4
I,
2
- Right
II
3
- Left
II
3
Damper Arm Assembly
II
5
Rubber
II
1
Hand
s
Strip
Buffer
(2)
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
From Ser No
Issue
MA 1000 07P
1
I,
1
II
1
51
PO9696
Damper Rod
52
PO7426
Damper
53
PO7763
Plug Cover
54
74020030
Maincase
,I
1
55
59930044
Guide Bracket
11
1
56
59930160
Mounting
Angle
II
1
57
59930042
Mounting
Plate
58
PO6741
Plug 318"
59
PO7526
Spring
60*
PO6148
Solenoid
* NOTE: Items
60 and 61 are
bonded
(Mercury
Switch)
II
Solenoid
Black
Solenoid
together
II
1
II
1
II
and should
not
be ordered
separately.
1
5
PARTS LIST IDENTIFICATION
Ident
No
61*
Part
No
Description
3
II
4
I,
1
,I
3
II
1
,I
1
,I
1
,I
1
59910121
Catch
63
PO7764
Microswitch
64
59930037
Microswitch
67
59920128
Proximity
68
PO2969
Grommet
69
P11993
Proximity/Switch
70
PO7476
Voltage
76
74030070
Top Trim
I,
1
77
74020061
PCB Mainboard
II
1
74020064
EPROMfor
II
1
* NOTE: Items
60 and 61 are
bonded
Catch
MA 1000 07P
Adaptor
,
- Spindle
Issue
59930043
62
- Solenoid
From Ser No
Assembly
Bracket
Switch
Assembly
Pillar
Regulator
above
together
and should
not
be ordered
separately.
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
From Ser No
Issue
MA 1000 07P
i
79
74020060
Nosecone
81
74030020
Front
82
PO6979
Receptacle
83
PO6976
Plug
84
PO9407
Transistor
PMD16K60
85
PO9254
Transistor
Mounting
86
59930005
Transistor
Mounting
89
59920009
90
11
1
II
1
II
1
‘1
1
Kit
'1
1
Block
I'
1
Heatsink
1'
3
74020001
Plinth
II
1
91
PO1517
Clamp Plate
II
1
92
PO7882
Fuse Holder
II
1
Panel
Cytospin
3
12 Way
Housing
12 Way
z
- Mains Lead
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
Plate
From Ser No
Issue
MA 1000 07P
1
93
PO4654
Fuse Marking
94
P11130
Fuse 0.8
PO7884
Fuse Cap 240V FEIT 031-1663
1
PO7828
Fuse 2 Amp Slow Blow
1
PO7883
Fuse Cap 1lOV FEIT 031-1661
II
1
95
PO6755
Input
II
1
96
59930009
Terminal
II
1
97
PO7155
Relay
II
1
98
PO6102
Capacitor
Clip
‘1
1
99
PO7462
Capacitor
4700 yF
II
1
100
59920041
Tagboard
‘1
5
1
Amp Slow Blow
Block
Mains
Block
Pad
60 73 IML
Assembly
240V
PARTS LIST IDENTIFICATION
Ident
No
Part
No
Description
100
59920043
Tagboard
101
P11944
Rocker
102
PO6979
Receptacle
103
P11109
Mains Filter
104
59930001
Transformer
105
PO7807
Diode
106
59930116
Transformer
107
59930171
Spacer
108
PO7602
Black
59930156
Hinge Adjustment
Assembly
1lOV
Switch
Bridge
12 Way
From Ser No
Issue
MA 1000 07P
4
II
1
‘1
1
‘1
1
Plate
4
Rectifier
1
II
1
2
Neoprene
Buffer
Screw
1%" x 'h" Thick
1
2
HOME
RECOHMENDEDPIRSTLINE REPAIRKIT
Part
No
59920041
59920043
59920131
59930094
59930095
59930096
59930097
59930116
74010004
74010005
74020061
74020062
74020063
74020064
74030020
PO5606
PO6148
PO7155
PO7402
PO7431
PO7432
PO7437
PO7444
PO7462
PO7467
PO7476
PO7516
PO7524
PO7525
PO7595
PO7596
PO7763
PO7764
PO7807
PO9254
PO9351
PO9407
PO9638
P11109
P11944
- CYTOSPIN 2
Description
Tagboard Assembly 240V
Tagboard Assembly 1lOV
Opto PCB
Main Body - Locking Device
Locking Pin -. Locking Device
Top Cap - Locking Pin
Handle - Sealed Head
Transformer
Transformer
Plate Assembly 1lOV
Transformer
Plate Assembly 240V
PCB Mainboard
Programmed PAL
Programmed PAL
Programmed Eprom
Front Panel
Proximity
Switch (SW3)
Solenoid
Relay - LO 73 IMO
Motor - Type 55M Spec
Seal - V Ring
Seal - V8 - Motor Shaft
Top Cover Moulding
Disc Encoder
Capacitor
4700 nF
Opt0 Interrupter
Voltage
Regulator
Seal
Switch Mercury (SW4)
'0' Ring
Seal - Silicone
- Sealed Bead
Seal Moulded
Plug and Cover - Mercury Switch
Microswitch
(SW5)
Diode Bridge Rectifier
Mounting Kit
Brush Assembly - Motor
Transistor
- Darlington
- PMB 16K60
Ball Bearings
Mains Filter
Switch - Rocker (SWl)
47
HOME
10
LIST OF DRAWINGS
Page No
Cytospin
Circuit
Note:
3
llOV-250V
Diagram
Circuit
Diagram
- Main PCB
The PCB used on the Cytospin
3 is
component locations
will be used.
48
E740-1-l
49
F740-1-2
50
a common board,
not
all
HOME
110
I’ I
I
I -
?
a
I
CIRCUIT
DIAGRAM-MAIN
PCB
n
I
II
F740-1-2
HOME
SHANDON
CYTOSPIN
SOUTHERN
III
40
41
42
PRODUCTS
LTD
43
28
108
26
27
HOME
--
PLGh
SK11
WTlcY
1
-
RD
z-w)-WTXXI
3-m)
GYM
W-MN
4-m)
5-W)--
)--
,
GYM
,
RD
,
RD
GY
GY
RD
RD
BK
GY@K
6--m)-7-r
GY
8-w)--
CY@K
0
_ RD
BK
9-m)---
-3
1
tl
Cl
lo-==>-
1-L
-7
47mtJf
-*
11-m)-12-my
WTM
)
PL2%
1
2
f:
3&;
4
5
6
i
1
0
I
WTNL
RD
1 WXN
I
I 1’
GYM
I
I-
I
[GYBK
-------
I
PLGI
SK12
-
1
I
1I
t
RIA
4 '
L-cl
T
I
4
--
5.a
1
--
8
-10
:
9
10
11
I2
SENSOR P.C.B.
wlm
WlflD
i
w4>-5 )
WTrcR
WTIRD
6)
7 )--
I
wT/8N
ln2
WTBL
WTBK
1
VIBRATKX
SWITCH
SW4
LIDLOCKEDSWIICH
SW5
CIRCUIT
DIAGRAM-CYTOSPlN(llO-250V)
51
-RD
I
p
-11
I
I
I
f
I
HOME
APPENDIX
PRINCIPLES OF OPERATION
This
description
F740-1-2
E740-l-1
(1)
uses
Circuit
Circuit
drawing
numbers:
Diagram Main PCB
Diagram Cytospin
(110-250V)
OVERVIEWOF SYSTEM
The Cytospin
3 is a bench-mounted
centrifuge
with a range of
speeds from 200 - 2000 rprn. The time and speed required
are
entered
and displayed
digitally
by means of a keyboard and LED
displays.
The Cytospin
1
2
3
a number of
safety
features:
Overspeed
detection
Out of balance detection
Electronic
failure
detection
The Cytospin
the operator
(2)
3 incorporates
GENERAL (Ref
3 has been designed
to provide
from biological
specimens.
maximum protection
to
F740-1-2)
The Cytospin
3’s electronic
circuit
occupies
one PCB in the
It is connected
to the main instrument
by
nosecone
assembly.
This PCB replaces
the earlier
meansof a detachable
loom.
versions
as fitted
to the Cytospin
2 and is not retrofittable.
The PCB is partitioned
are described
below.
no analogue
setting-up
(3)
into well
The PCB is
procedure.
defined
factory
functional
calibrated
areas which
and requires
POWERSUPPLY
Mains power is supplied
to the machine via SW1 (the main on/off
The internal
circuitry
switch)
which is mounted on the plinth.
fuse, 0.8A for 250V operation
is protected
by FSl, a slow-blow
Interference
protection,
both from inter2A for 1lOV operation.
ference
getting
into the machine from the external
mains supply
and vice-versa,
is provided
by FLl.
The low voltage
supplies
for the machine are derived
from Tl,
this is a toroidal
transformer
to minimise space and temperature
It has two primaries
which are connected
in series
for
rise.
240V operation
or in parallel
for 1lOV operation,
as shown on
Two voltage
dependent resistors
Sl, S2 are
drawing E740-1-l.
connected
across
the primaries
to suppress any voltage
spikes
which are not attenuated
sufficiently
by FLl.
Tl has three
secondaries,
24V AC at 4A rms, 8-0-8V AC at 2A rms and 15V AC at
0.58 rms.
51
HOME
The 24V winding is used to supply power to the motor, lid
solenoid
and motor control
relay,
it is rectified
by diode
bridge Bl and smoothed by Cl, a 4700uF capacitor.
Both Bl and
Cl are situated
on the transformer
plate assembly in the
plinth.
From the transformer,
8V AC is fed to the main PCB, rectified
by Dll, D12 and C36, then regulated
by VR3 to provide
a +5V
3.
supply * The 12V AC winding is unused on the Cytospin
(4)
MICROPROCESSOR
UNIT
The microprocessor
system on the Cytospin
3 is centred
around
IC6, a Hitachi HD63A03Y 8-bit
microcomputer.
The clock signal
for the microcomputer
is provided
by the 4.9152 Mhz quartz
crystal
at X2 together
with capacitors
C245 and C25.
The system ROM is contained
in IC7 while the PLA at IC8 is used
for address decoding.
In the event of a power failure,
all
stored
programs are retained
in memory by the EEPROMat IC4.
Power failure
detection
and software
watchdog facilities
are
provided
by the MAX690 at IC2 and the PLA at IC5 respectively.
(5)
DISPLAY AND KEYBOARDCIRCUITS
The display
and keyboard driving
is multiplexed.
The LED’s
1 - 8 are scanned by a walking zero on port six of the
as are the seven segment displays.
microcomputer,
This allows
for increased
intensity
of display
for reduced current
consumption.
The walking zero is used to switch on one of the transistors
The transistor
supplies
the common anode of the
T16 to T23.
seven segment display
and another LED with 5V.
The other end
of the LED’s in the seven segment display
and the separate
LED
are pulled low through RN2 and R41.
This is done selectively
by the pattern being fed through from the darlington
driver
chip ICll.
ICll is
correct
mounted
memory mapped and driven by the processor
to power the
All the seven segment displays
are
display
segments.
in tuned pin sockets
for easy replacement.
The keyboard is of standard
touchpanel
construction
being
The rows of eight going
arranged
in three rows of eight.
vertically
down the keyboard are scanned by port 6 of the
microcomputer
at a frequency
of about 100 Hz, therefore
response
is immediate.
52
HOME
The three horizontal
rows are monitored
by IC13 which is memory
Connection
to the keyboard is through a single
in line
mapped.
18-way Berg connector
(PL3) via a short tail
to the top of the
keyboard.
LED 9 is
(6)
driven
by IC14 and supplied
from pull
up resistor
R40.
MOTORDRIVE CIRCUIT
The motor control
output provides
a regulated
current
to the base
of the motor drive power darlington
transistor
TRl.
v
- 1.5
This current
is approximately
-CD
amp, where V,, is the
300
voltage
at the collector
of transistor
Tll and 300 is the
value in ohms of R28.
V,, is controlled
by a unity gain longtailed
pair amplifier
made up from T8, T9 and TlO.
The
amplifier
compares the collector
voltage
V,, with an input
taken from a reservoir
capacitor
C26 to adjust
the base current
of Tll.
The voltage
appearing
at capacitor
C26 is controlled
by a series
of one millisecond
pulses which are generated
at
These pass through inverter
IC8c
pin 14 of the microprocessor.
and a resistor
R27, which provide
the correct
charge level
and
rate control
for the capacitor.
(7)
SOLENOID AND RELAY DRIVE CIRCUITS
The solenoid
which is activated
to allow the lid to be opened and
the relay which is driven to allow motor current
to reach the
motor both operate
from +24 volts
and have similar
drive
circuits.
Because of the inductive
nature of both devices,
by-pass
diodes D6 and D7 are fitted
to re-circulate
switched
current.
The solenoid
is activated
by taking IC6 pin 23 low and the relay
In each case this switches
on a pnp
by taking IC6 pin 15 low.
transistor
(T15 and T13) connected
to +5 volts,
which provides
base current
to an npn transistor
(T14 and T12), which itself
The base current
to the drive transistor
in
powers the device.
each case can be clamped to ground to prevent
the transistor
this is done using an open
switching
on.
For the relay,
collector
handgate IC17 driven by KEs and mRT providing
a safety
interlock.
740-l-91
53
HOME
The lid release
solenoid
can only be driven under software
control.
Should the software
control
fail,
the open lid key will
not operate.
In an emergency the lid release
solenoid
can be
opened manually.
This is done by turning off the mains supply
and inserting
a thin screwdriver
through the hole provided
in the
left
side panel.
The hole is covered
by a plastic
cap.
(8)
SPEED WATCHDOG
AND OUT OF BALANCE
The out of balance detector
mercury switch is used to generate
an
mAT by being latched
on the NM1 decode/general
interface
PAL (IC5).
This will cause the drive
to the motor to be cut via IC17 and the
plinth
relay to release,
causing
regenerative
braking.
In addition,
the BAL LED will
light
showing an extreme fault
condition.
The Cytospin
3 has to be switched
OFF then ON to
recover
from the situation.
Other signals
that cause the same
sequence of events include
hardware overspeed.
The ability
to
detect
imminent power fail
is not used.
The Cytospin
3 has a software
based overspeed
detection
circuit
that will
cut the drive,
cause regenerative
braking and light
the
again is by switching
OFF then ON.
LED. Recovery
The microprocessor
monitors
the angular speed by monitoring
the
output of the slotted
opto mounted beneath the motor.
This signal
is fed to the board PL2a pin 3 then squared up using the Schmitt
inverter
IC18 and fed into the microprocessor’s
interval
timer
input on IC6 pin 9.
Running in parallel
to this software
overspeed
detector
This circuit
is comprised
hardware overspeed
detector.
Essentially
its associated
discrete
analogue
components.
circuit
is a frequency
to voltage
converter.
is a true
of IC3 and
the
The squared up opto signal
is differentiated
using C18, IC3 and R3
to produce a pulse for every edge detected.
This pulse is then
rectified
using D2 and used to charge C19, should the speed be too
high Cl9 will be unable to discharge
to a low voltage.
The average
of the voltage
on Cl9 is generated
across C20 using R4, it is this
voltage
that is a reflection
of the speed.
The final
stage using POT2 and IC3 is a comparator producing
a low
This signal
is latched
by the PAL IC5
when overspeed
is detected.
creating
an NHI and the usual machine shutdown.
POT2 is used to
set the voltage
threshold
and hence the frequency
threshold.
Due
to the variation
in component value and the variation
in the Vf of
D2, the circuit
must be calibrated
using a known frequency
of 2.6
KHz on the spin input to produce
the overspeed
warning.
740-l-91
54
!
HOME
The circuit
once calibrated
should never require
recalibration.
A
feature
of the software
is the anti-jam
mechanism.
This checks to
see if any pulses are being generated
on the rotor speed opto
interrupter
input line.
If the microprocessor
expects
rotor
rotation
because power is applied
to the motor and none is
detected,
then drive power will be removed after
a period of
approximately
4 seconds.
This is to prevent motor damage if the
motor is jammed, but also acts as a safeguard
against
opto
interrupter
failure.
(9)
NMI, RESET, HARDWARE
WATCHDOG
AND OPEN COLLECTORLOGIC
The FU3%has the same action
on the open collector
logic
as the NRT
signal.
The two signals
being added together
in IC8 to produce the
CVT signal
driving
IC17, cutting
drive and driving
the plinth
relay
RLl via T14 to cause motor drive isolation
and regenerative
braking.
The m
signal
will be produced by the MAX690 (IC2) in one of two
Should the power fail,
prior
to the ILogic levels
being
situations.
affected,
at 4.5 volts
the microprocessor
is reset and will not be
released
from reset until
such time as the power rail has risen
above 4.5 volts
and a further
1.6 seconds has elapsed.
The NRT signal
will also be produced should a watchdog signal
not
This signal
is an indication
that the
be produced on IC6 pin 22.
its absence indicates
software
software
is operating
normally,
corruption.
(10)
MOTOR, OPT0 DISC, LID LOCK AND BALANCESWITCH
The motor used is a 24V permanent magnet type, mounted in line with
The power to the motor is controlled
by relay
the rotor assembly.
RLA and transistor
TRl (E740-l-l),
these components are mounted on
When the machine is stopped or de-energised,
power to
the plinth.
the motor is removed and it is short circuited
by contacts
RLAl,
RLA2 (connected
in parallel)
of relay RLA. Thus, if the machine is
stopped the motor is regeneratively
braked (ie it acts like a
generator
with a short circuit
output).
When the machine is
started
RLA is energised
and power can be supplied
to Ml via TRl.
Because this transistor
under certain
conditions
is called
upon to
dissipate
up to 6OW, it is mounted on a heatsink
which projects
out
The control
signal
for TRl is derived
of the rear of the machine.
from the main PCB and is described
above.
55
HOME
The lid of the Cytospin
is locked by means of a mec.hanical latch
which can only be released
by means of a solenoid
Sol 1 (E740-l-l),
the control
signal
for which comes from the main PCB; So as to
inform the microprocessor
control
system if the lid is locked
or
are incorporated
in the circuit,
SW3 and SW5.
not, two switches
Switch SW3 is a reed relay proximity
switch which is activated
by a
The switch itself
is mounted in the trim on top
magnet in the lid.
As the lid is closed
the magnet is brought closer
of the nosecone.
to SW3 and when it is within range the switch will close.
To
ensure that the lid is fully
locked,
a microswitch
is incorporated
in the lid latch assembly (SW5), this switch detects
if the lid
Since SW3 and SW5 are in series,
a signal
latch
is not fully
home.
(5V) will only be present
to the main PCB when the lid is fully
shut (F740-l-l).
In the event that the head is loaded with a non-balanced
load and
the machine started,
an out of balance switch is incorporated
to
inform the microprocessor
to switch the machine off.
This switch,
SW4, consists
of two contacts
situated
above a small bead of
If the machine vibrates
the mercury is agitated
and
mercury.
this signal
is latched
on the
bridges
the gap between the contacts,
Because the mechanics of the
main PCB and stops the machine.
suspension
system exhibit
different
characteristics
depending upon
whether the rotor is accelerating
or decelerating,
the switch
is
then taken out of the circuit
by RLA3 when the motor is turned off.
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