MILESTONE

MLS-1200 PYRO

MICROWAVE ASHING MODULE service manual

Thank you for having selected our system and welcome in the ever growing world club of

Milestone users.

We are sure that you will be completely satisfied with this new tool entering your laboratory.

We invite you to read carefully this service manual and to keep it in reach for convenient and fast consulting.

For any possible clarification or any request of intervention please contact either our

Representative in your country: or Milestone at the following address:

MILESTONE s.r.l.

Customer Service Dept.

Via Fatebenefratelli 1/5

24010 SORISOLE (BG) - ITALY

Phone (4 lines): &&

Italy country code

Telefax: O "

Italy country code

35

Bergamo city code

35

Bergamo city code

573857

Milestone number

575498

Milestone number

INDEX OF CONTENTS

1 INTRODUCTION

2 GENERAL WARNINGS

3 MEASURING OF POWER

4 REMOVAL OF CABINET COVER

5 ELECTRICAL CONTROLS

5.1 SAFETY CONNECTION (POWER CORD EARTH)

5.2 DOOR SWITCHES

5.3 HEATING TRANSFORMER TEST

5.4 HIGH VOLTAGE TRANSFORMER TEST

5.5 CAPACITOR TEST

5.6 DIODE TEST

5.7 MAGNETRON CONTROL

5.8 ANODE CURRENT

5.9 HIGH FREQUENCY LEAKAGE

5.10 EXHAUST SYSTEM

5.11 TEMPERATURE SENSOR

5.12 TEMPERATURE MEASUREMENT SYSTEM

6 DESCRIPTION OF COMPONENTS

6.1 HOW TO INSTALL THE MUFFLE

7 TEMPERATURE ADJUSTMENT

8 ELECTRIC WIRING DIAGRAMS AND EXPLODED VIEW

9 ^ERROR MESSAGES

9.1 HOW TO CONTROL THE RAM BATTERY'S CHARGHE

10 TROUBLESHOOTING LIST

11 RECOMMENDED SPARE PARTS

MLS-1200PYRO Service Manual (rev. 1/1996)

1 INTRODUCTION

Each Milestone unit is accurately tested before leaving the manufacturing plant. All units are provided with a Quality Test Certificate. A proper use and a proper and accurate service are however required to assure long and safe operation of the system.

READ THESE INSTRUCTIONS CAREFU11 Y

BEFORE OPERATING THE UNIT

GENERAL WARNINGS

In order to operate under safe conditions and avoid any danger or risk of accidents, the following rules must be strictly followed :

1) Always disconnect the unit from the mains power before any repair.

2) Before switching the unit on again after every repair, it is necessary to make sure that:

- all the internal connections are correctly soldered;

- all the cables are insulated and don't come into contact with either the door or the sharp edges of the unit;

- both the electrical and mechanical connections are virtually faultless;

- no modifications have been made to the built-in safety devices;

- the spare parts are those required by the manufacturer.

WARNING : do not operate the unit if the slightest doubt exists that it is not properly working !

DO NOT INTRODUCE ANY METAL PARTS OR METAL CONTAINERS

INTO THE MICROWAVE WORKING CHAMBER

3) The microwaves generated inside the MLS-1200 PYRO unit have a frequency of 2450

MHz and reach the highest absorption in aqueous matrices causing a rapid increase in temperature This may represent a danger for the operator. Therefore avoid any exposure teethe microwave field generated by the magnetron.

POWER MEASUREMENT

Proceed along the following guidelines :

1) take out of the middle of the unit the complete muffle, leaving the ceramic base placed at the bottom of the working-chamber (see Picture 1)

Picture 1

2) create the following program

STEP

1

POWER

1000 W

TIME

1 minute

3) fill in a cylinder-shaped pyrex container (diameter approx. 20-22 cm) with 1 liter of water

(± 25 ml);

4) introduce the pyrex container into the working-chamber

5) bend the thermocouple as far as it reaches the water.

6) read on the display placed on the front of the unit, the initial temperature of the water (Ti)

7) start the previously stored program at point 2

8) at the end of the program, check final temperature (Tf) (as soon as it becomes stabile) reading the display again.

9) calculate the working power using the following formula:

WORKING POWER (W) = 70 x {Tf - Ti)

This procedure is according to IEC Norms no.705.

NOTE: Ti and Tf temperature measurements must be extremely accurate, as a ± 1°C deviation is equivalent, when calculating the power, to a difference of ± 70 W; it is therefore recommended to repeat the test several times.

REMOVAL OF THE CABINET COVER

1) Disconnect the unit from mains power to prevent any undesired switching on.(picture 1 and 2);

2) Loosen the two cross screws on the right and left sides of the unit; (picture 3);

3) Loosen the cross screws placed on the back of the unit (picture 4);

4) Remove the cover by lifting it from the back (picture 5)

5) Unscrew the middle screw on the base of the back panel. It is now possible to reach the high voltage connections (picture 6)

Picture 1

Picture 2

Picture 5 Picture 6

WARNING: HIGH VOLTAGE IN THE CAPACITORS

BEWARE : never bypass the serial switch to the 220 V line located on the left back side of the unit. But you have to bypass it if you want to make a faulting, (see Figure below)

ELECTRICAL CONTROLS

When repairing high power transformer, capacitors, relays and resistance as well as

Magnetron, it is possible to get in contact with high voltage. Therefore it is necessary to use only instruments with high voltage insulation higher than 5000 Volt. Personnel must take the utmost care not to get in contact with high voltage.

5.1 SAFETY CONNECTION (POWER CORD EARTH)

Check connection of safety contact to the plug of the unit. The resistance must not exceed

"lOOmOhm.

5.2 DOOR SWITCHES (PIN 33062 and P/N 33064)

The unit is provided with 4 safety switches. The two switches placed on the upper right and left sides of the MLS-1200 PYRO unit are operated by closing the door. They open when pushing the door handle downwards. This means that when the door is closed, these switches are also closed. When the door is open, these switches are open too. The lower switches are safety switches and are also activated by the door arm.

To check the correct functioning of the switches, use an electrical resistance Ohm-meter.

Right and left door-slide switches :

CLOSED DOOR: R = 0 ohm OPEN DOOR : R = infinite

Right and left door-handle switches:

CLOSED DOOR: R = 0 ohm OPEN DOOR: R = infinite

When the door is closed, the switches are open and viceversa.

BEWARE: when pushing down the door handle, be careful that the upper left switch is activated before the right one.

Defective switches must be destroyed to prevent future use.

5.3 HEATING TRANSFORMER TEST PIN 33046

CAUTION: During the operation about 2300 VAC get to the high voltage terminals. While using the measurement instruments, keep your hands, tools, etc. off the high voltage terminals.

To check the heating transformer, proceed as follows :

1) Disconnect the unit and loosen the capacitor with an insulated screwdriver.

2) Disconnect the connecting cable between capacitor and high voltage transformer.

3) Connect the Voltmeter to the terminals of the magnetron wires.

4) Connect the unit to the mains power and start a program with microwave power (e.g.

1000 W for 1 minute). The heating voltage should be around 4.6 VAC.

ATTENTION: Disconnect the unit from the mains power before disconnecting the Voltmeter.

If the Voltmeter indicates no voltage, connect the wires with the capacitor, set the

Voltmeter to the correct measurement range and check if 220 V (230 V) are available.

If the input voltage is normal but there is no voltage in the heating wires, it will be necessary to replace the transformer.

The resistance at the terminals of the heating transformer must be:

= 13 Ohm on the primary winding.

= 0,8 Ohm on the secondary winding.

5.4 HIGH VOLTAGE TRANSFORMER TEST PIN 33044

As about 2300 VAC are available at the secondary winding of the transformer during operation, no high voltage measurement should be carried out. Normally, it is enough to check the current flow to make sure of the state of the transformer.

1) Disconnect the unit, loosen the capacitor with an insulated screwdriver and disconnect the transformer wires;

2) Measure the resistance value between the high voltage terminals with an electrica resistance meter; it should turn out to be about 40 Ohms.

3) If a much lower, a much higher or an infinite resistance is measured, the transformer is faulty and must be replaced.

8

5.5 CAPACITOR TEST PIN 33051

The consequence of an open capacitor is that no high voltage gets to the magnetron. A shorted capacitor normally interrupts the fuse for current overload. An electrical resistance meter can be used to check a discontinued or shorted capacitor.

1) Unplug the unit from the power grid and wait 1 minute before getting in contact with the high voltage parts; loosen the capacitor with an insulated screwdriver and disconnect the capacitor wires.

2) Set the resistance meter to the highest value and measure the resistance between the capacitor terminals. The resistance meter must indicate for a short time interval the flow between the terminals; when the capacitor is charged, it must indicate an infinite value.

3) If the resistance meter shows a continuous flow between the terminals of the capacitor, or no current flow at all is detected, it is necessary to replace the capacitor.

4) Measure the resistances between both capacitor terminals and the cover of the capacitor.

The resistance meter must indicate an infinite value.

5.6 DIODE TEST P/N 33054

- Disconnect the unit and wait for 1 minute.

- loosen the capacitors with an insulated screwdriver and disconnect the capacitor wires and the diodes connections.

- Measure the resistance at the highest value terminals. Then invert the wires and observe the flow on the measuring instrument. A normal diode has an infinite resistance in one direction and a weak resistance in the opposite direction. If it shows a current flow or an infinite resistance in both directions, it is necessary to replace the diode.

NOTE: Resistance meters with a battery of less than 6 to 9 Volts are generally not suitable for checking the diodes. In the case of an infinite resistance in both directions, the unit should first be used on a diode which has been proved not to be faulty before replacing a diode when there's no need for it.

5.7 MAGNETRON CONTROL PIN 33040

The magnetron is shown in picture 1.

Ceramic cap

HF washer

Picture 1

1) Disconnect the unit from the mains power and wait for one minute;

2) disconnect the high voltage wires from the wire terminals and measure the resistance between magnetron terminals;

3) connect the resistance meter between the magnetron wires and the magnetron case

(earth); the read-out of the resistance meter must be an infinite value. A lower resistance means that the magnetron is defective and must be replaced.

4) Check the two terminals. The resistance should be maximum 300 milliOhm. A higher resistance means a fault in the wires or cut-off wires and sometimes also the magnetron has to be replaced.

Absolutely do not use the unit in case of missing or faulty washers. The washer wrapped all around the magnetron prevents any microwave leakage between magnetron and magnetron drive.

CAUTION: the ceramic cap must not get damaged or scratched by metallic parts, as even very small scratches on the ceramic surface sensibly shorten its life.

10

5.8 ANODE CURRENT

The anode current gives an indication on the status of the magnetron. When the magnetron becomes "old", the resistance at the wires is increased and the anode current is decreased.

For the measurement of the anode current, follow these instructions:

- Disconnect the unit and take.the plug out, wait for 1 minute.

- Check the Ohm value of the resistance connected with the diode's grounding. The correct value is 10 Ohms.

- Connect a Voltmeter with a measuring range of minimum 5 V at the resistance terminals.

- Connect the unit and start a program with 100 % power. Do not forget to introduce a microwave absorbing charge (for example water) into the unit.

- Measure the voltage, which with magnetron type 2M121 must be about 4,3 VAC.

NOTE: Don't touch the Voltmeter during the measurement.

The anode current can be measured by the following equation:

IA = VR/10 = 4,3 V/10 Ohm = 0,43 A

Figure 1

The anode current for the Magnetron type 2M121 must be 430 mA (+/-10 mA) at 100% power.

With an anode current lower than 410 mA, it is necessary to replace the magnetron. It may also be that some component is not properly working in the high voltage parts (capacitors, diodes, linefwhich might result in a lower current.

11

5.9 HIGH FREQUENCY LEAKAGE

IMPORTANT: a high-frequency leakage test must be carried out before and after every repair.

To perform this test, use the Leak Tester P/N 33700 supplied by Milestone.

The test is as follows:

1) Switch on the Leak Tester.

2) Operate the unit at full power (1000 W) for one minute.

3) Check the MLS-1200 PYRO unit for leakage gently moving the Leak Tester.

Start from the upper right side of the door and proceed clockwise all around the door until you get back to the starting point. Carry out a similar test on all the visible screening.

THE VALUE MUST ALWAYS BE LOWER THAN 5 mW/cm

2

MEASURED AT 5 cm DISTANCE FROM THE UNIT SURFACE

A

NOTE: In order to perform a correct high frequency leakage check, the unit must be positioned in such a way that the meter can easily be used perpendicularly to the lower door edge.

IMPORTANT: in case of radiofrequency leakage, do not absolutely operate the unit until it has been perfectly repaired.

Possible causes of microwave leakage are the following :

1) The door doesn't close well against the working chamber.

2) A hinge is broken.

3) The radiofrequency door washer is damaged.

4) The door is bent or the unit presents some other visible damages which could cause a microwave leakage.

5) There are faulty parts in the connections.

6) There are faulty parts in the microwave generator.

The following points must always be checked after every repair:

1) Has the RF magnetron washer been correctly installed?

2) Are the working chamber and the microwave drive in perfect conditions?

3) Can the door be properly closed, and do the safety devices operate correctly?

IMPORTANT: Do not connect the unit for any reason until the above mentioned circumstances have been carefully checked and, if necessary, seen to.

12

5./0 EXHAUSTING FAN

The MLS-1200 PYRO units have built-in exhausting and ventilation fan placed on the back of the unit (see picture 2)

Picture 2

The aiKstream generated by this system allows:

- cooling of the parts surrounding the muffle, i.e. hardware

- removing particles, fumes and odours from the working chamber

- conveying fresh air (oxigen) to the samples to facilitate burning.

13

- Exhaust motor p.n. 50045

TECHNICAL SPECIFICATIONS

Voltage

Frequency

Current

Power input

= 220 V

50 Hz

= 0,16 A

35 W

Air Volume

Speed

Noise level

Admissible Temp.

64 m3/h

2700 round/mm

58 dBA

150°C

Figure 2

5.11 TEMPERATURE SENSOR - P/N 33086

The MLS-1200 PYRO unit has two built-in temperature sensors (Klixon). One is located on the magnetron walls and disconnects the microwave emission in case of overheating, at a temperature of110°C(230°F).

The second sensor is placed on the metal side of the microwave chamber; it is activated whenever there is microwave generation inside the unit with no absorbing charge (the heating elements are the charge). If however the temperature of the external side of the chamber exceeds 80°C (176°F) the temperature sensor will disconnect the microwave emission. The display will show "DOOR NOT CLOSED"

This will last for a few minutes until temperature goes back to values below 69°C (156°F), and the Klixon is reactivated.

14

5.12 TEMPERATURE MEASUREMENT SYSTEM

Temperature Measurement System in MLS-1200 PYRO includes the following parts:

1. Thermocouple type K NiCr-Ni with measuring range -200°C + 1300°C, which is installed in the back of the unit (see Picture 3).

Picture 3

The thermocouple is introduced inside the working chamber into the muffle where temperature measurement takes place (see figure 3)

Thermocouple with ceramic tube protection

Figure 3

W

Muffle

15

2. Electronic Card with ATC-300-S display with measuring range between O°C and 1250°C.

The ATC-300-S card is placed on the front panel for easy temperature reading (see

Picture 4)

Picture 4

The ATC-300-S card receives signal in mV from the thermocouple and converts it into mV graduated value to:

- attain temperature reading on the display

- generate an analogic signal for microprocessor control of temperature

- generate an analogic signal for external connections (recorder, PC, etc.)

16

CALIBRATION OF THE THERMOCOUPLE

The following comparison table allows to check correct functioning of the NiCr-Ni thermocouple according to DIN-IEC 584-1 Norms.

Temp.

800

900

1000

1100

1200

1300

200

300

400

500

600

700

°C

-200

-100

0

20

50

100

NiCr - Ni typ K

mV

At max

12,207

16,395

20,640

24,902

29,128

-5,891

-3,533

0

0,789

2,022

4,095

8,137

33,277

37,325

41,269

45,108

48,828

52,398

± 2,5°C

Under -40°C and over 1000°C the tolerance of the thermocouple is subject to substantial variations.

17

CALIBRATION OF THE ATC 300-S ELECTRONIC BOARD AND DISPLAY

Technical Specifications:

Temperature Range:

Solution:

Accuracy:

Output Voltage:

Supply Voltage:

ATC-300 S

0°C... 1250°C

± 1K(°C)

0,083% (MBEW)

0V...10V

12V and 5V

P1 P2 P3

Figure 4: Top View ATC-300 with Potentiometers and Jumpers

CALIBRATION OF ATC-300 AFTER ASSEMBLY

Step Jumper Settings

1. Preparation

2. Zero Adjustment Icm mx « t t » |

1

8

3. Gain Control

@ ® E H ® © © ©I

Calibration and Checks

Connect ATC-300 without Sensor;

With potentiometer P1 adjust voltage of Pin

"OUT" to 0,000V ±1mV the dispaly shows 000 ± 1 at jumper pins 1 (-) und (+J a voltage of

22,772 mV needs to be applied; at pin 8 should be a voltage (toward pin 1) of - 555 mV ± 5mV (+ Zero- offset); at pin

OUT should be a voltage of 4400mV ±40mV note the actual value for step 5;

4. Display Adjustment (2

• S B * • • •

5. CAL-U Adjustment

18

the voltage of 22,772 mV is still applied at pin 1 and pin 2; with P2 adjust the displayed number to 550 units;

6. Normal Operation lomayp

" with potentiometer P3 adjust voltage at pin

OUT to the value measured in step 3; set jumpers for normal operation;

SERVICE CHECKS

Step Jumper Settings

7. Preparation

8. Zero Adjustment

1 8

9. Processor

Adjustment

10. Normal Operation

11. Display Control

TP

Calibration and Checks

Connect ATC-300 without Sensor; check voltage at Pin "OUT" for:

0,000 V ± 1 mV both displays show 000 ± 1 units (LCD and

LED); check voltage at Pin "OUT" for:

4400mV ± 40mV display must show 550 ± 1 set jumpers for normal operation; plug in sensor and check for correct display value; bridge "TP"-pads; all segments must be illuminated (-1888);

Remark:

On the event that under normal operation the display doesn't exactly show the sensor's temperature a correction can be achieved via potentiometer P1 (Zero Adjust). The correction must not exceed a range of ± 2K (°C) Bigger differences could result from a malfunction of the ATC-300.

Different Display Values: As an average value the CPU generates the dispayed temperature

^ (LCD) out of 250 samples which takes some 1-2 seconds delay time compared to the values shown on the red LED display. This effect can occasionally lead to a difference of 3°C-4°C between the two displays.

19

DESCRIPTION OF COMPONENTS

1) LCD Display

2) Keyboard

3) Attachment of control panel to MLS-1200 PYRO

4) Control panel body

Picture 1: Control panel of MLS-1200 PYRO unit

20

Removal of the cabinet cover of the 240 Remote Control

- Disconnect the 50 pin connection between MLS 1200 PYRO and 240 Remote Control.

- Remove the polypropylene fixing screw located on the leftside of the Remote Control.

- Unscrew the 2 screws located on the front and the 4 screws located on the rear side of the

240 Remote Control.

- Remove the cover by raising the front and pushing towards to the back.

1) Eprom

2) Ram

3) Microprocessor

4) Back-up Battery

5) Buzzer

6) Contrast Regulation by potentiometer

Picture 2

The C.P.U. Board is located inside the Remote Control 240

21

1) Left safety switch (is activated by lowering the door-handle)

2) Left safety switch (is activated by opening the door)

3) Fan cooling for high voltage circuit

4) Door handle for opening/closing

5) Hole for quartz tube introduction (only for Pyro Sulphate Ashing system with SAM35)

Picture 3: Left-side view of MLS-1200-PYRO

22

1) Right safety switch (is activated by lowering the door-handle)

2) Right safety switch (is activated by opening the door)

3) Front panel (with acid resistant coating)

4) Fan-exhaust system

Picture 4: Right-side view of MLS-1200 PYRO

23

1) Magnetron

2) Safety switch

3) 220V line inlet and 16A/T fuse

4) Electrical connection to external modules (options)

5) 50 pin connection for 240 Remote Control

6) Magnetron fan

7) High voltage capacitor

8) Heating transformer

9) High voltage transformer

10) High voltage diode

11) Exhaust motor

12) Cooling Fan For HV traFo

Picture 5: Back-view ofMLS-1200 - PYRO

1) Power supply 220V and 16A/T fuse

2) Interface board for 240 Remote Control

3) Radiofrequency filter RLC

4) Toroidal transformer

5) Cooling fan

6) Relays board

7) Microwave diffuser motor

8) Power board for Magnetron

9) Power supply board

10) ATC-300 Electronic board and Display

24

Picture 6: Over-view of MLS-1200PYRO

25

Picture 7 below, shows all the parts included in the complete muffle kit p/n 50075.

Picture 7

You can easily recognize all the items with their exact part number in the Figure 1 next page.

26

TOP PLATE

P/N 50053

CERAMIC SUPPORT

BACK-RIGHT

P/N 50055

CERAMIC SUPPORT

BACK-LEFT

P/N 50054

HONEY COMB CERAMIC STOPPER

P/N 50046

MUFFLE FURNACE

CERAMIC SUPPORT

FRONT LEFT

P/N 50056

\

PLATE HOLDER OF

HEATING ELEMENTS-

P/N 50058

THERMOCOUPLE

PROTECTION TUBE

P/N 50064

CERAMIC SUPPORT

FRONT RIGHT

P/N 50057

FRONT FRAME

P/N 50059

MUFFLE DOOR

P/N 50060

Figure 1 = Top view of the complete muffle kit. (p/n 50075)

BASEMENT

P/N 50123

27

WARNING

BEFORE USING REMOVE THE PLASTIC DISC PLACED ON THE

CEILING OF THE WORKING CHAMBER TO PROTECT THE

MICROWAVE DIFFUSER DURING THE TRANSPORT

I

I r

Picture 8 below, shows how to proceed to this operation

Picture 8

28

6.1 HOW TO INSTALL MUFFLE KIT PIN 50075

INSIDE MLS-1200 PYRO UNIT

1. Position the bottom plate P/N 50123 inside the PYRO working chamber (Figure 1)

2. Position the 4 ceramic supports P/N 50054 - 50055 - 50056 and 50057 at the four corners of the working chamber (Figure 1).

3.

4.

Figure 1

Place the muffle P/N 50005 on the 4 ceramic supports carefully introducing at the same time the thermocouple through the hole in the backwall of the muffle itself (Figure 2)

Cover the end of the thermocouple placed inside the muffle with the ceramic protection tube P/N 50064 (Figure 2).

Figure 2

29

5.

6.

Introduce the plate P/N 50058 inside the muffle with heating elements turned to the rear side of the muffle in close contact with the thermocouple (Figure 3)

Place the front frame P/N 50059 on the front ceramic supports to perfectly posizion the muffle (Figure 3).

Figure 3

7. Place on top the ceiling P/N 50053 to cover the muffle and the front frame (Figure 4).

Figure 4

8. Close the muffle access inside the muffle using the door P/N 50060 (Figure 4)

30

HOW TO ADJUST THE TEMPERATURE VALUE

When the temperature value (T2) reading on the display of the MEGA 240 Control Terminal does not match with the actual temperature reading on the display in front of the MLS-1200

PYRO unit, new calibration of the system is required. This procedure has to be followed also in case of replacement of some active parts of temperature measurement or control, e.g.:

- K Thermocouple

- ATC-300-S

- Interface board

- CPU board

How to proceed:

1. Open the M240 terminal control by removing the 6 screws (2 in front and 4 behind).

2. Remove the M240 top panel (the one with the display) and lay it beside the base panel

(which contains the CPU) without removing the connections between the two parts. (See

Figure 1).

Oil—IQ

F1=WORK p=o,o

T1=0

F2=EDIT

T2=1000

(FiJ (F2) [F3J (F4j (F5j [F6J (F7J

0

©00000E)

0 000©

ISTARTI • i n i n m ra

0000

Figure 1: M240 open view

EZ:

©

In this way, it is possible to calibrate the CPU (T2 potentiomenter) and read the values on the display

3. Install the following microwave program:

Time = 1 h

Power = 1000W

T2 = 1000°C

31

4. Read the temperature value on the red display located on the front frame of the Pyro (see

Figure 2)

Read the correct value of T2 on the red display

Figure 2

5. By means of a screwdriver, regulate the 10 Kohm potentiometer (T2) on the CPU board

(see Figure 1). Adjuste the potentiometer (T2) until the remote control display value T2 corresponds to the front frame LED Display of the MLS-1200 Pyro.

6. Start the microwave program installed in point N. 3

7. Repeat the operations in points N. 4 and 5 at approximately every 100°C until reaching

1000°C.

P.S. The difference allowed at 1000°C between the real value on the red dispaly and that read ontheM240is1-2°C.

32

8 ELECTRIC WIRING DIAGRAMS

Figurei: Electric diagram of MLS-1200 PYRO

CO ro

I

Q.

0)

6

I

. A

35 FUSE 10A

13 MAGNETRON CONTROL BOARD

46 CONTROL CABLE

CO

34

18

19

20

21

21A

13

14

15

16

17

1

2

3

4

5

6

7

8

9

10

11

12

28

29

30

31

32

33

22

22A

23

24

25

26

27

33A

34

35

36

37

33259

33716

33930

33053

33051

33319

33300

33301

33727

33062

33064

33066

33068

33100

33072

33074

33077

33965

33080

50054

50055

50056

50057

50046

33086

33086

50058

33090

33304

33258

33040

33042

33044

33046

33048

50045

33054

50064

33058

33060

Reference Number Part Number Description

43

44

45

46

47

48

49

38

39

40

41

42

50

51

52

53

54

33916

33726

33930

33973

33597

33096

33598

33599

33316

33221

30333

50059

50060

50053

50005

50123

50045

Magnetron

Magnetron fan

High voltage transformer

Heating transformer

High voltage resistance 4MOhm 2W

Exhaust motor

High voltage diode SCL 11 Z 2B5

Ceramic tube for thermocouple

Resistance 10Ohm

Capacitor for Magnetron fan

Safety microswitch on right/left door

Door microswitch on right/left door

Magnetron control board

Relay board

Line filter 20A/220V

Diffuser axle 75mm in PTFE

Diffuser motor MW-220W

Complete door (working chamber)

Heating elements

Microwave diffuser

Back-left ceramic support of muffle

Back-right ceramic support of muffle

Front-left ceramic support of muffle

Front-rigth ceramic support of muffle

Boat stop (ceramic stopper)

Thermic switch of ceiling of the microwave chamber

Thermic switch of magnetron

Support for heating elements

Rubber feet

Fan 220V, 50/60Hz

LCD Display for 240 Remote Control

Flat keyboard for 240 Remote Control

Power supply 12V/5V/24V

Complete CPU Board for 240 Remote Control

Capacitor 1,14uF(50Hz)

Capacitor 1uF(60Hz)

Toroidal transformer

10A fuse for magnetron control board

16A fuse (line fuse)

Interface board complete with 50 pin Cable for 240

Remote Control

50 pin cable for 240 Remote Control

ATC-300-S Electronic board + Display

Remote Control for Mega 240 (CPU included)

Thermocouple Type K

Fixing element for thermocouple (I)

Safety switch 220V

Fixing element for thermocouple (II)

Fixing element for thermocouple (III)

Cable between interface board and relay board

Frontal frame for MLS 1200 PYRO

Complete chassis cover for MLS 1200 PYRO

Front frame of muffle

Muffle door

Ceiling of muffle

Muffle

Bottom Plate of muffle

Cooling Fan For HV traFo

35

POWER CARD

12V

LOWER RIGHT

SWITCH

DOOR UPPER

LEFT SWITCH

• 1

r

V

WHITE/

BLUE

WHITE/

RED

WHITE/

VIOLET

WHITE/

BLUE 2

WHITE/

BLACK

WHITE/

BLACK

4 - AC

IC1

VDR:

C1

VIOLET BLUE

AUTOSUPPLY

I 4AC

IC2

4-

4-

IC4

AC

IC3

VDR2

JC2

RED RED

VIOLET BLUE

MAGNETRON FAN

DIFFUSER MOTOR

AC

L1

VDR3 RED

]C3

BLUE

GREEN BLUE

HEATING

TRANSFORMER

COOLING FOR HV TRAFO

C4

CS

BLACK BLACK

ORANGE BLACK

RED BLUE

RING TRANSFORMER

MICROWAVE

VENTILATOR

POWER GRID INLET

I

'

ST16

BLUE BLUE

NEUTRAL LINE

SWITCH

I 1

V

1

BLUE

RED

POWER CARD INLET

Figure 3: Relays card, side-view of components

STISM

STIS I

STIS

STIS

5 T 1 5

S T I S

£ T l s | 2 t |

5TI5J23, 1

STIShi V—r-

ST1 S[22| 1

S I 1 5 | 2 l | '

5TIS

STIS

JTI5

STIS

JT.5I7 U

STIS 2l>k

STIS I

STI 5

36

|STI1 S l i

3T3

ST4

STS

S T (

517

! 7 I

! ' t

3

3

3

3

3

3

3

3

—-

.

! * 5

| S T I I

|STI3

11 2S0V

1C1

2 * * V A <-tJ27S»iC T l 0

' r 1 0 0 V

HI

270B

- C T H

- I 2 V

S110

ST1J

ST1]

S T I I i—b

1ST

to

1

13

|STU

27011

CD

J70R

-CZh

t l 2 5 0 V

1C2

.„„

in,

! I

»" I' r-i

-i:v I

U 3 5 0 V

IC3

V 7 ^ V77T P - ' v D R J _ C 3

3 *! 1 I

STI (1

STJ I

STI 1

h

VORS

27SV4C

Figure 4: Electric diagram of relays card

12

VAC

37

22

VAC

12

VAC

— STU ST1£ STI3

Figure 5: Power supply, side-view of components

38

Figure 6: Electric diagram of power supply

39

O

P"

O t 12

IC2

S 3 C

"In o

R2

O

L

5 A

70 22 804

I I I I

C4

o

-

3 7

T T T

X

o

Figure7: Power board, side-view of components

o

<C

CD

6

O

40

12 V Command Inlet"+ -"

1 - ST10/Relays board

2 connected with 1

3 -f ST10/Relays board

220 V "INLET"

4ST1

6

5ST1

220 V "DOOR SWITCH"

7 door switch

8 door switch

9 not used

220 V Exit "Trafo"

10 not used

11 N High voltage transformer (not used)

12 L1 High voltage transformer

Figure 8: Electric diagram of Power board

Lnl

11

41

Interface Connections on 240 Remote Control

Primer

Centronics

Analog/

RS232 (-3-)

PC Balance

RS232(-1) RS232I-2-)

Backview

PC-Connection RS 232/COM1

COM1

• • • • •

• • • •

6 7 8 9

ST11

?

3

1

—<

>

• —

TxD

RxD

4

i fc

DTR

5 GND

6

—i

7

ft

9

-

J20

PC-Connection

PC-Cable

PC COM2

RxD

TxD

GND

RTS

CTS

5

6

7

8

2

3

4

MW 2000

2

3

TxD

RxD

5

GND

Balance-Connection RS 232/COM2

COM2

3 4 5

• • •

• • • •

6 7 8 9

ST12

Balance-Connection p

-I

1

—t •

3

TxD

RxD

4

t

fe

DTR

5 GND

1

6 , k S.hfl

7

4

^

8

9

Balance-Cable white brown

„ qreen

13

•

•

'I

- • 3 vellow

COM2

A 1 2 3 4 5 "\

[ VAVr

V 6 7 8 9 J female

Analog - output - Connection

analogoutput

3 4 5

• • • •

6 7 8 9 female

4

5

1

7

3 fi

7

R

9

GNDA

T2

T1

Pressure

GND

GNDA

AY14

AY8

AY7

GNDA

GND analog ground digital ground

T2 = external temperature: 1 °C = 8mV

T2 = external temperature control calibration

42

ST4

o

P7 ST8

o

ST19

EPROM

LL

Batt.

ST2

o.

ST22 IO r

ST6

H-Ctrl

PI 2 3 4 5 6

•

T2

ST21

ST9

D/A Power

P9 P

5

! P10

o

ST12

o

ST11

o

9: CPL/ card, fop weiv of fA?e main components

43

(22

- y y -

JGB -OED-

•OZB

m

•UiiU-

•GEO-

" E

•css> ft

1

EPROM

•Q3i>

. 5

1

8

RAM

-Tom- HTn> -ran-

5

o

5?

a

I

an

-CED-

-CSD-

CE

-C2D-

s

-fKT> o

0

< ^ >

-CSD-

•C25>

-CEB3-

-Cga>

o* -am-

EB

^Q

a.a

2 CEO

-CSD-

• C B J T - -GSO-

-cszo*

-I tC3 H

-C3Dg

•03D-

-CSS- -CS>

Figure 10: CPU card, top view of the components

44

ERROR MESSAGES

In case the operator has any difficulties with the control terminal, e.g. is in a sub-menu and does not know how to come out of it, the basic rule is to push the STOP key to go back to the

Main Menu. Switching ON/OFF the unit will cause resetting and going back to Main menu.

Work programs remain unaltered.

This chapter will list the most common error messages

1) "DOOR NOT CLOSED"

As an added safety the magnetrons are provided with overheating thermal safety switch. In the remote event of thermal overheating, the following will appear:

>DOOR NOT CLOSED<

CONTINUE = CLOSE DOOR

ABORT=STOP

If this error message is not due to the door, interrupt the program and check if for example the cavity is empty. After cooling the unit can be again operated regulary.

2) "FATAL ERROR: RAM"

The unit is provided with a Lithium battery to save the storage in memory of working programs.

If the following message appears:

FATAL ERROR: RAM check ram or battery

It is supposed that the battery is exhausted and the operator has to call for immediate service.

Otherwise there may be modifications in the stored programs when the power is off. The unit itself for the rest is ready for use. After the error message, press the STOP key and under EDIT

O delete all programs (KILL ALL PROGRAMS) and set a new one.

In case the unit is newly installed, or the EPROM memory has been replaced, keep the STOP key pressed until you hear a whistle, which informs that the unit is initilized.

45

9.1 HOW TO CONTROL THE RAM BATTERY'S CHARGE

You can check RAM - battery - buffer when power-off the system and messure the voltage between the RAM-PINS (GND-VCC)

Proceed as follow:

- Detect (with diagram in Figure 1) the position of RAM and battery in the CPU board.

P I 2 3 4 5 6

[1 Pressure

T2 T1

Figure 1 = CPU card, top view of the main components

- Take a multimeter and select VDC (V-)

- Measure the voltage as shown in Figure 2

+

vcc

27 26 25 24 23 22 21 20 19 18 17 16 15

RAM

1 2 3 4 5 6 7 8 9 10 11 12 13 14

GND

Figure 2

RAM Pin Table

Pin No Name

14 GND

28 VCC

20 CS

Ground

5V buffer voltage off the RAM

Chip Select 5V

46

When you can't measure 5V between Pin 14 and Pin 28 check in the CPU board the batterybuffer circuit below: vcc brf

R21

D"D 1

Battery

RAM PIN 28 / 20

L r 7 < c«:

_ i _

C12

If the voltage measured is lower than 2.5V. replacement of the battery is needed sRENATA

= SWISS MAOE

Gnd

Figure 2: Schematic of lithium battery

47

10 TROUBLESHOOTING LIST

PROBLEM

- Difficulties in switching on the M240

Control Terminal: display dark or fully lightened or crossed by vertical and horizonatal lines.

- Some keys on the M240 keyboard do not allow data input into the program.

- Independent block of working program with return to the main menu.

- The working program presents parameters that are not set by the operator.

- Difficulty in breaking the working program.

- Autostart of a working program.

- Microwave emission is not controlled when preset temperature value (T2) is reached.

- The T2 value on the display of M240

Control Terminal does not correspond to the actual reading on the red dispaly placed on the PYRO front frame.

DIAGNOSIS

A) Check perfect connection of 50 pins cable between PYRO and M240 Control

Terminal.

B) Repeat switching on of the unit by MAIN

SWITCH placed on the front frame of the

PYRO.

C)Open the M240 Control Terminal and check all connections between CPU, power supply and display.

D) If after these checks A, B and C the problem still remains, replace in sequence:

- Interface board

- 50 pins connection cable

- CPU board

- Display board

A) Open the M240 Control Terminal and check the connection between the keyboard and CPU

B) Replace EPROM

C) Re-initialize the EPROM by switching on the MAIN SWITCH and simultaneously push the STOP key on the M240 keyboard

A) Replace the EPROM.

B) Initialize the new EPROM (push simultaneously MAIN SWITCH and STOP TASTE on M240 Control Terminal).

C) Replace the CPU board.

A) Check the 50 pins connecting cable:

- some pins may be bent or broken

- some cables of the 50 pin connector

(male or female) may be unsoldered or detached or interrupted.

- connection between PYRO unit (interface board) and M240 Control Terminal may be loose: carefully fasten the screws in the connecting plugs.

B) Check any short circuit on the interface board.

C) Adjust the potentiometer T2 on the CPU board (see chapter 7).

48

PROBLEM

The red display on the front frame of the unit shows absurd values e.g. 1 or 1323

The unit doesn't switch on

There is no microwave emission

After 5 second magnetron heating time the program doesn't start and the display shows "DOOR NOT CLOSED"

DIAGNOSIS

A) If the dispaly shows figure 1:

- replace the ATC-300-S card (see paragraph 5.12).

B) If the display shows ± 1323:

- check connection between the thermocouple and the ATC-300-S card.

- replace the thermocouple.

- Fuse 16AT-250V power mains grid;

- Front Switch;

- RLC Filter

- Safety switch on the cover

- Magnetron;

- Heating transformer;

- Right and left door-slide switches;

- Right door-handle switch;

- Fuse 10AT-250V on power board;

- The magnetron fan is malfunctioning which causes magnetron overheating and activation of the temperature sensor located on magnetron.

- The door is not perfectly closed;

- Left door-handle switch;

- Exhaust fan is blocked (with consequent over-heating of the uW chamber therefore the temperature sensor intervenes).

- The temperature sensor (klixon) is defected.

11 RECOMMENDED SPARE PARTS

P/N 333CH Fuse 16AT-250V

P/N 33300 Fuse 10AT-250V

P/N 33940 CPU Board Mega 240 (installed inside the Remote Control)

HIGH FREQUENCY LEAKAGE TEST (SEE PARAGRAPH 5.9}

P/N 33700 Leak tester microwave radiation measurement