Sanyo MDF-U537D, MDF-U537, MDF-U333 Service Manual

Service
Manual Biomedical freezer

SANYO Electric Biomedical Co., Ltd.

MDF-U333
MDF-U537

MDF-U537D

MDF-U537

ＳＭ７２１０１３９

Effective models

This service manual is effective following models.

Model name Model code

Voltage and Frequency

MDF-U537 823 168 51 115V 60Hz

823 168 52 220V 50Hz
823 168 53 220V 60Hz
823 168 54 230V 50Hz
823 168 55 240V 50Hz
823 168 56 115V 60Hz
823 168 57 110V 60Hz
824 168 58 230V 50Hz
824 168 59 220V 50Hz
824 168 60 240V 50Hz
825 168 61
825 168 62

MDF-U537D 823 169 51 115V 60Hz

823 169 52 220V 50Hz
823 169 53 220V 60Hz
823 169 54 230V 50Hz
827 169 55 240V 50Hz
823 169 56 240V 50Hz
823 169 57 230V 50Hz
823 169 58 115V 60Hz
823 169 59 110V 60Hz
823 169 60 220V 50Hz
823 169 61
823 169 62

MDF-U333 823 170 51 115V 60Hz

823 170 52 220V 50Hz
823 170 53 220V 60Hz
823 170 54 230V 50Hz
823 170 55 240V 50Hz
823 170 56 110V 60Hz
823 170 57 230V 50Hz
823 170 58 240V 50Hz
823 170 59 220V 50Hz
823 170 60
823 170 61
823 170 62

Contents

･ Feature 1

･ Specification MDF-Ｕ 333 3

MDF-Ｕ 537 5

MDF-Ｕ 537D 7

･ Dimensions MDF-Ｕ 333 9

MDF-Ｕ 537 10

MDF-Ｕ 537D 11

･ Refrigeration circuit 12

Refrigeration circuit principle diagram MDF-Ｕ333 15

Refrigeration circuit welding points MDF-Ｕ 333 16

Refrigeration circuit principle diagram MDF-Ｕ 537 17

Refrigeration circuit welding points MDF-Ｕ 537 18

Refrigeration circuit principle diagram MDF-Ｕ 537D 19

Refrigeration circuit welding points MDF-Ｕ 537D 20

･ Electrical Parts 21

･ Specification of sensor 24

･ Control specification 25

･ Wiring diagram 34

･ Circuit diagram 37

･ Components on P.C.B. 38

･ Test data 39

･ Parts loyout 49

･ User’smanual 50

Features

＜ＭＤＦ－Ｕ３３３＞

＜ＭＤＦ－Ｕ３３３＞

＜ＭＤＦ－Ｕ３３３＞＜ＭＤＦ－Ｕ３３３＞

■ HFC refrigerant

Refrigerant circuit contains HFC refrigerant that effect to environment little.

Latest cooling system reduces negative factor to global environment. With ambient
temperature at 35℃, while temperature of inside chamber maintains -30℃.

■ PCM structure

PCM structure reduces amount of organic solvent.

■ Temperature control function
Unified temperature control range for same categories realized to set -20℃, which

is suitable for reagent preservation.

■ Specification unified

Unified specification for same categories, which also realized to unify performance for
high/low temperature alarm (SV is changeable in the range ±5～±15℃), power failure

alarm, remote alarm terminal, setting memorization by non-volatile memory.

Adopt new microprocessor system for display panel and keypad makes operation easily.

■ Self diagnosis function

Abnormal condition for temperature sensor is indicated by self-diagnosis system.

■ Validation

Control panel enables zero “0” adjust for validation.

■ New door latch mechanism

New door latch is adopted in order to close door surely for reagents.

It is also available to use individual lock mechanism.

■ Insulation wall thickness

Unit has necessary insulation performance for each temperature range.

Combination of PCM and frame form makes 610mm for frame size commonly.

■ Option

Internal temperature observation system is option.

Unit has communication function corresponding to it.

−1−

Features

＜ＭＤＦ－Ｕ５３７，５３７Ｄ＞

＜ＭＤＦ－Ｕ５３７，５３７Ｄ＞

＜ＭＤＦ－Ｕ５３７，５３７Ｄ＞＜ＭＤＦ－Ｕ５３７，５３７Ｄ＞

■ HFC refrigerant

Refrigerant circuit contains HFC refrigerant that effect to environment little.

Latest cooling system reduces negative factor to global environment. With ambient
temperature at 35℃, while temperature of inside chamber maintains -30℃.

■ PCM structure

PCM structure reduces amount of organic solvent.

■ Temperature control function
New cooling system realizes to set -20℃, which is suitable for reagent preservation.

■ Specification unified

Unified specification for same categories, which also realized to unify performance for
high/low temperature alarm (SV is changeable in the range ±5～±15℃), power failure

alarm, remote alarm terminal, setting memorization by non-volatile memory.

Adopt new microprocessor system for display panel and keypad makes operation easily.

■ Self diagnosis function

Abnormal condition for temperature sensor is indicated by self-diagnosis system.

■ Validation

Control panel enables zero “0” adjust for validation.

■ New door latch mechanism

New door latch is adopted in order to close door surely for reagents.

It is also available to use individual lock mechanism.

■ Draw box for reagent preservation

100mm for depth of box makes things easily to arrange and take in & out.

(Adopted in bottom chamber of MDF-U537/U537D)

■ Compressor protection function

Sensor detects compressor’s warming up to control unit running.

− 2 −

Specification

MDF-U333

Items Specification

Model description Biomedical freezer

Model Number MDF-U333

Outer dimension
Inner dimension W 490 × D 485 × H 1290 mm

Effective chamber capacity 274 lit.

Exterior Zinc galvanized steel w/powder polyester coating (PCM)

Interior Polystyrene resin

Insulation Rigid polyurethane foam

Outer door 1 pc, Zinc galvanized steel w/powder polyester coating (PCM)

Latch 1 pc

Door lock 1 pc

Basket

Accessories

Others Defrosting spatula 1 pc, key 1 set, 4 card holders

Caster 4 pcs

Leveling legs 2 pcs (with caster)
Access hole φ 30mm. 1 place in left side.

Weights 81 Kg

Evaporator Tube on sheet type (function both evaporator and shelf)

Condenser Wire and tube type

Compressor Hermetic type 225W

W 614 × D 733 × H 1620 mm

(Max)

(L) 4 pcs Inner dimension: W446×D369×H220 mm
(S) 1 pc (for bottom column) Inner dimension:

W

487×D221×H155mm

Refrigerant

Cooling performance -30℃ (internal 1/2h air temperature, AT：35℃, no load)

Internal temperature control
range

Power supply Local voltage

HFC refrigerant

R-134a

-20℃~-30℃
(AT：5℃~35℃、no load)

− 3 −

MDF-U333

Items Specification

Temperature controller

Microprocessor controlled system with non-volatilized memory.
Temp. set range : -18℃～-40℃

Temperature sensor Thermistor

Temperature display

High/Low
Temperature

Alarm

Power failure

Remote alarm
contact

LED digital display (green colored) by 1℃.
Range : -50℃～50℃
Changeable SV±5℃～15℃. (Initial SV±10℃)
ALARM lamp brinks and buzzer sounds intermittently

(about 15 min. delay)
Remote alarm contact: turns ON during power failure alarm.
ALARM lamp brinks, buzzer sounds intermittently, remote alarm
contact turns ON during power failure alarm.
Remote alarm terminal 3P: contact capacity DC30v, Max2A, N.O.
–COM. (During power failure, temperature alarm: ON)
ALARM lamp
BUZZER: Buzzer key
ALARM TEST: Alarm test key

Control panel

Operation
panel

SET: To switch the SV and PV

＞: To shift the set digit
∧: To change the SV

DEF: Defrost key

Rear

Key lock function

Power switch (Breaker switch)
Battery switch: Power failure alarm switch

Press ＞ key for five seconds
L0: Unlock L1: Lock
When each sensor is in fault,

Self diagnosis function

Error code and internal temperature are displayed alternately.
Remote alarm contact turns ON with buzzer sounds.

Power switch Breaker switch

Compressor protection Overload relay

Chart recorder: MTR-G85

Option

Mounting kit: MPR-S7(for bottom mounting)
: MDF-S740T(for top mounting)

− 4 −

Specification

MDF-U537

Items Specification

Model description Biomedical freezer

Model Number MDF-U537
Outer dimension (Max) W 804 × D 772 × H 1802 mm
Inner dimension W 658 × D 607 × H 1272 mm

Effective chamber capacity 482 lit.

Exterior Zinc galvanized steel w/powder polyester coating (PCM)

Interior Polystyrene resin

Insulation Rigid polyurethane foam

Outer door

Latch 2 pcs

Door lock 1 pc

Basket

Accessories

Others Defrosting spatula 1 pc, key 1 set, 14 card holders

Caster 4 pcs

Zinc galvanized steel w/powder polyester coating (PCM)
2 pcs (upper and lower compartment)

(M) 6 pcs (upper compartment)

W

Inner dimension:

290×D536×H136 mm

(S) 8 pcs (lower compartment)

W

Inner dimension:

290×D536×H100mm

Leveling legs 2 pcs (with caster)
Access hole φ 30mm. 1 place on rear.

Weights 131 Kg

Evaporator Tube on sheet type (function both evaporator and shelf)

Condenser Wire and tube type

Compressor Hermetic type 350W

HFC refrigerant

Refrigerant

R-407D

Cooling performance -30℃ (internal 1/2h air temperature, AT：35℃, no load)

Internal temperature control
range

-20℃~-30℃
(AT：5℃~35℃、no load)

Power supply Local voltage

− 5 −

MDF-U537

Items Specification

Temperature controller

Microprocessor controlled system with non-volatilized memory.
Temp. set range : -18℃～-40℃

Temperature sensor Thermistor 2P

Temperature display

High/Low
Temperature

Alarm

Power failure

Remote alarm
contact

LED digital display (green colored) by 1℃.
Range : -50℃～50℃
Changeable SV±5℃～15℃. (Initial SV±10℃)
ALARM lamp brinks and buzzer sounds intermittently

(about 15 min. delay)
Remote alarm contact: turns ON during power failure alarm.
ALARM lamp brinks, buzzer sounds intermittently, remote alarm
contact turns ON during power failure alarm.
Remote alarm terminal 3P: contact capacity DC30v, 2A, N.O. –COM.
(During power failure, temperature alarm: ON)
ALARM lamp
BUZZER: Buzzer key
ALARM TEST: Alarm test key

Control panel

Operation
panel

SET: To switch the SV and PV

＞: To shift the set digit
∧: To change the SV

DEF: Defrost key

Rear

Key lock function

Power switch (Breaker switch)
Battery switch: Power failure alarm switch

Press ＞ key for five seconds
L0: Unlock L1: Lock
When each sensor is in fault,

Self diagnosis function

Error code and internal temperature are displayed alternately.
Remote alarm contact turns ON with buzzer sounds.

Power switch Breaker switch

Overload relay
Detect temperature near compressor by thermistor sensor to control

Compressor protection

compressor during overload.
Alarm: Error code and internal temperature are displayed alternately.
Remote alarm contact turns on with buzzer sounds.
Chart recorder: MTR-G85

Option

Mounting kit: MPR-S7(for bottom mounting)
: MDF-S740T(for top mounting)

− 6 −

Specification

MDF-U537D

Items Specification

Model description Biomedical freezer

Model Number MDF-U537D

Outer dimension

Inner dimension

W 804 × D 772 × H 1802 mm

(Max)

Upper chamber W 658 × D 607 × H 589 mm
Lower chamber W 658 × D 607 × H 603 mm

Effective chamber capacity 452 lit.

Exterior Zinc galvanized steel w/powder polyester coating (PCM)

Interior Polystyrene resin

Insulation Rigid polyurethane foam

Outer door

Zinc galvanized steel w/powder polyester coating (PCM)
2 pcs (upper and lower compartment)

Latch 2 pcs

Door lock 1 pc

(M) 6 pcs (upper compartment)

W

290×D536×H136 mm

W

290×D536×H100mm

Accessories

Basket

Inner dimension:
(S) 8 pcs (lower compartment)
Inner dimension:

Others Defrosting spatula 1 pc, key 1 set, 14 card holders

Caster 4 pcs

Leveling legs 2 pcs (with caster)
Access hole φ 30mm. 2 places on rear.

Weights 136 Kg

Evaporator Tube on sheet type (function both evaporator and shelf)

Condenser Wire and tube type

Compressor Hermetic type 350W

HFC refrigerant

Refrigerant

R-407D

Cooling performance -30℃ (internal 1/2h air temperature, AT：35℃, no load)

Internal temperature control
range

-20℃~-30℃
(AT：5℃~35℃、no load)

Power supply Local voltage

− 7 −

MDF-U537D

Items Specification

Temperature controller

Microprocessor controlled system with non-volatilized memory.
Temp. set range : -18℃～-40℃

Temperature sensor Thermistor 2P (upper and lower compartment)

LED digital display (green colored) by 1℃.

Temperature display

Range : -50℃～50℃
Selectable to display upper or lower compartment by switch.

High/Low
Temperature

Alarm

Power failure

Remote alarm
contact

Changeable SV±5℃～15℃. (Initial SV±10℃)
ALARM lamp brinks and buzzer sounds intermittently
(about 15 min. delay)
Remote alarm contact: turns ON during power failure alarm.
ALARM lamp brinks, buzzer sounds intermittently, remote alarm
contact turns ON during power failure alarm.
Remote alarm terminal 3P: contact capacity DC30v, 2A, N.O. –COM.
(During power failure, temperature alarm: ON)
ALARM lamp
BUZZER: Buzzer key
ALARM TEST: Alarm test key

Control panel

Operation
panel

SET: To switch the SV and PV

＞: To shift the set digit
∧: To change the SV

DEF: Defrost key
TOP/BOTTOM: Switch key to display upper or lower compartment.

Rear

Key lock function

Power switch (Breaker switch)
Battery switch: Power failure alarm switch

Press ＞ key for five seconds
L0: Unlock L1: Lock
When each sensor is in fault,

Self diagnosis function

Error code and internal temperature are displayed alternately.
Remote alarm contact turns ON with buzzer sounds.

Power switch Breaker switch

Overload relay
Detect temperature near compressor by thermistor sensor to control

Compressor protection

compressor during overload.
Alarm: Error code and internal temperature are displayed alternately.
Remote alarm contact turns on with buzzer sounds.
Chart recorder: MTR-G85

Option

Mounting kit: MPR-S7(for bottom mounting)
: MDF-S740T(for top mounting)

− 8 −

Dimensions

＜＜＜＜MDF-U333＞＞＞＞

−9−

Dimensions

＜＜＜＜MDF-U537＞＞＞＞

−10−

Dimensions

＜＜＜＜MDF-U537D＞＞＞＞

−11−

Refrigeration circuit

MDF-U333 Unit：ｍｍ

Parts description Specification

Evaporator

Dehydrator

Capillary tube

Condenser assembly A

Condenser assembly B

Frame pipe

Evacuation and vacuum
pressure

Refrigerant and oil

Refrigeration circuit spec.
and welding points

Type Tube on sheet
Material Aluminum (φ 8.0)

Type of molecular sieves

４A-XH9（134 stamped）

Charged q’ty 8±1g
Resistance 0.686MPaG （7Kgｆ／㎠ G）

Dimension φ 1.8×(φ 0.65)×2000mm
Resistance indicator color White
Type Wire and tube
Dimension

w

480×P40×30 columns

Type Wire and tube
Dimension

w

480×P40×30 columns

Note: Lower 2 columns are used
in desuper circuit.

Material C1220T-1/2H
Dimension

φ 4.0×

ｔ

0.5

Evacuation time: over than 20min. by 2 ports (high pressure and low
pressure side). (N2 exchange)
When charged, vacuum pressure is lower than 1.0torr
（pump capacity： 300L/min）

Refrigerant : R-134a Charged q’ty : 226±5g
Oil : CF－32 Charged q’ty : 230±10cc
Oil additive: n-pentane Charged q’ty : 14g

Refer to following pages

−12−

Refrigeration circuit

MDF-U537 Unit：ｍｍ

Parts description Specification

Evaporator

Upper (1)
Lower (1)
Bottom (3)

Dry core

Type 9lines×1column×5pcs

Material Aluminum (φ 8.0)

Type D-S032T
Manufacturer SANYO
Solid core 50cm

Capillary tube
(Total number: 2)

Resistance 0.725MPaG （7.4Kgｆ／㎠ G）
Dimension φ 1.8×L4500
Resistance indicator color Blue

Condenser assembly
front (Total number: 4)

Frame pipe

Type Wire and tube
Dimension

Material C1220T
Dimension

Evacuation and vacuum
pressure

Evacuation time: over than 20min. by 2 ports (high pressure and low
pressure side). (N2 exchange)
When charged, vacuum pressure is lower than 1.0torr
（pump capacity： 300L/min）

Refrigerant and oil

Refrigerant : R-407D Charged q’ty : 301±5g
Oil : CF－32 Charged q’ty : 280±10cc
Oil additive: n-pentane Charged q’ty: 19g

Refrigeration circuit spec.
and welding points

Refer to following pages

3

w

480×P40×6 columns

L

φ 4.0×

ｔ

0.5×

7470

−13−

Refrigeration circuit

MDF-U537D Unit：ｍｍ

Parts description Specification

Evaporator assembly

Upper (1)

Type 9lines×1column×5pcs

Lower (1)
Bottom (2)

Material Aluminum (φ 8.0)

Lower entrance (1)

Dry core

Type D-S032T
Manufacturer SANYO
Solid core 50cm

Capillary tube

Upper compartmnt Lower compartmnt
Resistance 10.3Kg/㎠ G 9.9Kg/㎠ G
Dimension φ 1.8×L4000 φ 1.8×L3000
Resistance indicator color Yellow Red

Condenser assembly
front (Total number: 4)

Frame pipe

Type Wire and tube
Dimension

Material C1220T
Dimension

Evacuation and vacuum
pressure

Evacuation time: over than 20min. by 2 ports (high pressure and low
pressure side). (N2 exchange)
When charged, vacuum pressure is lower than 1.0torr
（pump capacity： 300L/min）

Refrigerant and oil

Refrigerant : R-407D Charged q’ty : 357±5g
Oil : CF－32 Charged q’ty : 280±10cc
Oil additive: n-pentane Charged q’ty : 23g

Refrigeration circuit spec.
and welding points

Refer to following pages

3

w

480×P40×6 columns

φ 4.0×

ｔ

0.5×L7470

−14−

Refrigeration circuit principle diagram

＜＜＜＜MDF-U333＞＞＞＞

−15−

Refrigeration circuit welding points

＜＜＜＜MDF-U333＞＞＞＞

−16−

Refrigeration circuit principle diagram

＜＜＜＜MDF-U537＞＞＞＞

−17−

Refrigeration circuit welding points

＜＜＜＜MDF-U537＞＞＞＞

−18−

Refrigeration circuit principle diagram

＜＜＜＜MDF-U537D＞＞＞＞

−19−

Refrigeration circuit welding points

＜＜＜＜MDF-U537D＞＞＞＞

−20−

Electrical Parts

MDF-U333

Compressor

Starting relay

Overload relay

Starting capacitor Rating 100μF,160VAC 100μF,160VAC 30μF,300VAC
Running capacitor Rating 25μF,220VAC 20μF,220VAC 5μF,400VAC

Temp. control relay

Switching power supply

Temperature sensor

P.C.B.

Battery

Battery switch

Breaker switch

Type C-2SN220L0W C-2SN220L2W C-2SN220L5W

Code 80771120 80771122 80771125

Rated voltage (50/60Hz) 100 / 100 , 110 -- / 115 220,240 / 220
Winding resistance C-S(Aux) 5.8Ω 7.2Ω 30.6Ω
C-R(Main) 1.6Ω 2.0Ω 7.8Ω

Type AMVL-180A AMVL-180A AMVL-300A
Pick up voltage(50Hz) AC91V〜111V AC91V〜111V AC185V〜217V
(60Hz) AC108〜128V AC108〜128V AC215〜232V
Drop out voltage(50Hz) AC30〜65V AC30〜65V AC60〜120V
(60Hz) AC30〜75V AC30〜75V AC69〜132V

Type P24KU P19KU P10MU

Action to the temp. (No current)

OFF 150±10℃ 150±10℃ 130±8℃

ON 85±10℃ 85±10℃ 69±10℃

Action to the current (AT25℃) 24.0A 19.5A 10A

Operation time 6～15 seconds 6～15 seconds 6～15 seconds

Non-Action to the temp. (80℃）

Non-Action

Action 8.0A within 15 minutes 7.4A within 15 minutes 3.4A within 15 minutes

Type G4F-11123T G4F-11123T G4F-11123T

Contact capacity AC220V,20A AC220V,20A AC220V,20A

Coil DC12V DC12V DC12V

Type ZWS10-12/J ZWS10-12/J ZWS10-12/J

Input

Rated output DC12V,0.85A DC12V,0.85A DC12V,0.85A

Type 502AT-1 502AT-1 502AT-1
Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃

Type DF-333 DF-333 DF-333

Type 5HR-AAC 5HR-AAC 5HR-AAC

Rating 6V 1100MAH 6V 1100MAH 6V 1100MAH

Type SLE6A2-5 SLE6A2-5 SLE6A2-5

Rating AC250V 4A AC250V 4A AC250V 4A

Type BAM215131 BAM215131 BAM215131

Rating AC250V 15A AC250V 15A AC250V 15A

AC110V,60Hz AC115V,60Hz AC220-240V , 50/60Hz

6.1A more than
30 minutes

AC100-240V
50/60Hz,0.3A

5.4A more than
30 minutes

AC100-240V
50/60Hz,0.3A

2.5A more than
30 minutes

AC100-240V
50/60Hz,0.3A

−21−

g

Electrical Parts

MDF-U537

Compressor Type C-2SN350L0R C-2SN350L5S C-2SN350L5S

Starting relay Type AMVL-180A AMVL-300A AMVL-300A

Overload relay Type P18AU P10MU P10MU

Starting capacitor Rating 100μF,160VAC 30μF,300VAC 30μF,300VAC
Running capacitor Rating 25μF,220VAC 5μF,400VAC 5μF,400VAC
Temp. control relay Type G4F-11123T G4F-11123T G4F-11123T

Solenoid valve Type G2R-1A-T G2R-1A-T G2R-1A-T
control relay Contact capacity AC250V,10A AC250V,10A AC250V,10A

Switching power supply Type ZWS10-12/J ZWS10-12/J ZWS10-12/J

Temperature sensor Type 502AT-1 502AT-1 502AT-1

Solenoid valve control Type 502AT-1 502AT-1 502AT-1
sensor Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃
Compressor protect sensor Type 502AT-1 502AT-1 502AT-1

P.C.B. Type DF-537 DF-537 DF-537
Battery Type 5HR-AAC 5HR-AAC 5HR-AAC

Battery switch Type SLE6A2-5 SLE6A2-5 SLE6A2-5

Breaker switch Type BAM215131 BAM215131 BAM215131

Solenoid valve coil Type NEVAC120V NEVAC220V NEVAC240V

Condensin

fan motor

Code 807764201 807763251 807763251
Rated voltage (50/60Hz)
Winding resistance C-S(Aux) 5.8Ω 30.6Ω 30.6Ω
C-R(Main) 1.6Ω 7.8Ω 7.8Ω

Pick up voltage(50Hz) AC91V〜111V AC185V〜217V AC185V〜217V
(60Hz) AC108〜128V AC215〜232V AC215〜232V
Drop out voltage(50Hz) AC30〜65V AC60〜120V AC60〜120V
(60Hz) AC30〜75V AC69〜132V AC69〜132V

Action to the temp. (No current)

OFF 120±8℃ 130±8℃ 130±8℃

ON 69±10℃ 69±10℃ 69±10℃

Action to the current (AT25℃) 18.5A 10A 10A

Operation time 6～15 seconds 6～15 seconds 6～15 seconds

Non-Action to the temp. (80℃）

Non-Action

Action 5.5A within 15 minutes 3.4A within 15 minutes 3.4A within 15 minutes

Contact capacity AC220V,20A AC220V,20A AC220V,20A
Coil DC12V DC12V DC12V

Coil DC12V DC12V DC12V

Input

Rated output DC12V,0.85A DC12V,0.85A DC12V,0.85A

Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃

Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃

Rating 6V 1100MAH 6V 1100MAH 6V 1100MAH

Rating AC250V 4A AC250V 4A AC250V 4A

Rating AC250V 15A AC250V 15A AC250V 15A

Rating 120V 50/60Hz 220V 50/60Hz 240V 50/60Hz
Type FU2-A051B1MP FU2-A051B5MP FU2-A051B5MP
Rating AC110-115V 50/60Hz 220-240V 50/60Hz 220-240V 50/60Hz
Thermal fuse 130℃ 130℃ 130℃

AC110-115V,60Hz AC220V,50/60Hz AC230V-240V,50Hz

4.0A more than
30 minutes

AC100-240V
50/60Hz,0.3A

2.5A more than
30 minutes

AC100-240V
50/60Hz,0.3A

2.5A more than
30 minutes

AC100-240V
50/60Hz,0.3A

−22−

g

Electrical Parts

MDF-U537D

Compressor Type C-2SN350L0R C-2SN350L5S C-2SN350L5S

Starting relay Type AMVL-180A AMVL-300A AMVL-300A

Overload relay Type P18AU P10MU P10MU

Starting capacitor Rating 100μF,160VAC 30μF,300VAC 30μF,300VAC
Running capacitor Rating 25μF,220VAC 5μF,400VAC 5μF,400VAC
Compressor relay Type G4F-11123T G4F-11123T G4F-11123T

Temp. control relay Type G2R-1A-T G2R-1A-T G2R-1A-T

Switching power supply Type ZWS10-12/J ZWS10-12/J ZWS10-12/J

Temperature sensor Type 502AT-1 502AT-1 502AT-1

Solenoid valve control Type 502AT-1 502AT-1 502AT-1
sensor Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃
Compressor protect sensor Type 502AT-1 502AT-1 502AT-1

P.C.B. Type DF-537D DF-537D DF-537D
Battery Type 5HR-AAC 5HR-AAC 5HR-AAC

Battery switch Type SLE6A2-5 SLE6A2-5 SLE6A2-5

Breaker switch Type BAM215131 BAM215131 BAM215131

Solenoid valve coil Type NEVAC120V NEVAC220V NEVAC240V

Condensin

(2 pcs.) Rating 120V 50/60Hz 220V 50/60Hz 240V 50/60Hz

fan motor

Code 807764201 807763251 807763251
Rated voltage (50/60Hz)
Winding resistance C-S(Aux) 5.8Ω 30.6Ω 30.6Ω
C-R(Main) 1.6Ω 7.8Ω 7.8Ω

Pick up voltage(50Hz) AC91V〜111V AC185V〜217V AC185V〜217V
(60Hz) AC108〜128V AC215〜232V AC215〜232V
Drop out voltage(50Hz) AC30〜65V AC60〜120V AC60〜120V
(60Hz) AC30〜75V AC69〜132V AC69〜132V

Action to the temp. (No current)

OFF 120±8℃ 130±8℃ 130±8℃

ON 69±10℃ 69±10℃ 69±10℃

Action to the current (AT25℃) 18.5A 10A 10A

Operation time 6～15 seconds 6～15 seconds 6～15 seconds

Non-Action to the temp. (80℃）

Non-Action

Action 5.5A within 15 minutes 3.4A within 15 minutes 3.4A within 15 minutes

Contact capacity AC220V,20A AC220V,20A AC220V,20A
Coil DC12V DC12V DC12V

Contact capacity AC250V,10A AC250V,10A AC250V,10A
Coil DC12V DC12V DC12V

Input

Rated output DC12V,0.85A DC12V,0.85A DC12V,0.85A

Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃

Rating 5kΩ,25℃ 5kΩ,25℃ 5kΩ,25℃

Rating 6V 1100MAH 6V 1100MAH 6V 1100MAH

Rating AC250V 4A AC250V 4A AC250V 4A

Rating AC250V 15A AC250V 15A AC250V 15A

Type FU2-A051B1MP FU2-A051B5MP FU2-A051B5MP
Rating AC110-115V 50/60Hz 220-240V 50/60Hz 220-240V 50/60Hz
Thermal fuse 130℃ 130℃ 130℃

AC110-115V,60Hz AC220V,50/60Hz AC230V-240V,50Hz

4.0A more than
30 minutes

AC100-240V
50/60Hz,0.3A

2.5A more than
30 minutes

AC100-240V
50/60Hz,0.3A

2.5A more than
30 minutes

AC100-240V
50/60Hz,0.3A

−23−

Specifications of sensor

The following show temperature and resistance characteristics on each thermistor sensor

(type 502).

Temperature

（℃）

－50 154.50 －7 17.92 12 8.17

－45 116.50 －6 17.16 13 7.85

－40 88.85 －5 16.43 14 7.55

－35 68.15 －4 15.74 15 7.27

－30 52.84 －3 15.08 16 6.99

－25 41.19 －2 14.45 17 6.73

－20 32.43 －1 13.86 18 6.48

Resistance

（kΩ）

Temperature

（℃）

Resistance

（kΩ）

Temperature

（℃）

Resistance

（kΩ）

－19 30.92 0 13.29 19 6.24

－18 29.50 1 12.74 20 6.01

－17 28.14 2 12.22 25 5.00

－16 26.87 3 11.72 30 4.18

－15 25.65 4 11.25 35 3.51

－14 24.51 5 10.80 40 2.96

－13 23.42 6 10.37 45 2.51

－12 22.39 7 9.96 50 2.14

－11 21.41 8 9.57 55 1.83

－10 20.48 9 9.20 60 1.57

－9 19.58 10 8.84

－8 18.73 11 8.49

−24−

Controlspecification

Controlspecification

ControlspecificationControlspecification

＜＜＜＜MDF-U333・・・・537・・・・537D＞＞＞＞

Keyandswitch

Keyandswitch

１．

１．

KeyandswitchKeyandswitch

１．１．

BZ ：When alarm lamp is blinking and buzzer sounds, buzzer and remote alarm
Output …………Force to turn off
In F25, setting value (time) is except for 000;buzzer will turn ON after the

setting time has passed. (This RING BACK function would be carried out in
s/n 110XXXXX or bigger)

：Buzzer is not turned off during alarm test.
：When alarm lamp is blinking and buzzer is off, buzzer will not turn on.
：When press this key during power failure, current internal temperature is

displayed for 5 seconds.

SET ：Press once to setting mode and press again to memorize the set value.
(It works as ENTER key)

DEF ：In PV display keep pressing the key over 5 seconds to start defrosting.

During defrosting, press the key to quit defrosting.
During defrosting, internal temperature and “dF” is displayed alternately.
During defrosting, high-low temperature alarm is cancelled.

When sensor error is occurred during defrosting, error code and internal

temperature is displayed alternately, and “dF” display is turned off.

During defrosting, only buzzer key is acceptable.

ALARM TEST：Press the key in PV display, alarm test will be start.

Press again then quit alarm test.
During alarm test, alarm lamp will blink and buzzer will sound intermittently.
Digital display will be turned off.
During alarm test, only alarm test key is acceptable.

：During setting mode, shift between the first digit and the second digit.

In PV display, keep pressing the key over 5 seconds to enter the key lock

mode. (“L0”display)

：During setting mode, count up the blinking digit. In PV display, keep

pressing the key over 5 seconds to enter the function mode (“F00” display)

TOP/BOTTOM ：This key is available only in MDF-U537D.
Initially TOP (upper compartment) temperature is displayed.
Press key to display BOTTOM (lower compartment) temperature.
Press this key during power failure to display compartment temperature for 5

seconds, that was not selected before power failure.

− 25 −

２．

２．Temperature control and High, Low temperature alarm

２．２．

<Temperature control>

Setting range ： -18℃～-40℃
Display range ： -50℃～+50℃
Setting method ：Press SET key and set the required value with key and

Key. Press SET key again to memorize the set value,

And then return to PV display.

Out of setting range : If change to out of setting range value by mistake and press

SET key , buzzer sound continuously for 1 second.

<Alarm>

High temperature alarm ：
When the internal temperature is higher than SV (+5℃～+15℃), alarm lamp and

digital display is blinking. After 15min.later, buzzer will sound and remote alarm

contact will turn ON. (initial value: +10℃)

Low temperature alarm ：

When the internal temperature is lower than SV（-5℃～-15℃）, alarm lamp and digital
display is blinking. After 15min.later, buzzer will sound and remote alarm contact will
turn ON. (initial value: -10℃)

Setting method ：
Keep pressing key over 5 seconds to enter function mode (“F00”).

Then press key to count up value. Change “F01” to input high temperature alarm

value, “F02” to input low temperature alarm value.
Set either “F01” or “F02” then press SET key to turn alarm temperature setting mode
to set required value with key and key.
Press SET key again to memorize value.

Out of setting range ：

If change to out of setting range value by mistake and press SET key, sound buzzer

continuously for 1second and remain in setting mode to maintain the setting value.

３．

３． Defrosting

３．３．

This function is different by each model code (products) .

a. In PV display keep pressing DEF key over 5 seconds, defrosting will be started.

Model code 001 (MDF-U333) --- Force to turn compressor OFF.

Model code 002 (MDF-U537) --- Force to turn compressor & solenoid valve OFF. (Use 1 solenoid valve)

Model code 003 (MDF-U537D)

--- Single compartment → Force to turn OFF solenoid valve at the ROOM lamp illuminated.

--- Both compartments → Force to turn OFF 2 solenoid valves & compressor.

b. Press again DEF key to quit defrosting.（Manual start and finish）

− 26 −

４．

４． Self diagnosis function

４．４．

E01 ： Temperature sensor (upper compartment temperature sensor for MDF-U537D)

is open circuit

E02 ： Temperature sensor (upper compartment temperature sensor for MDF-U537D)

is short circuit

E03 ： Lower compartment temperature sensor is open circuit （for MDF-U537D only）
E04 ： Lower compartment temperature sensor is short circuit （for MDF-U537D only）
E05 ： Compressor protect sensor is open circuit (for MDF-U537,U537D)
E06 ： Compressor protect sensor is short circuit (for MDF-U537,U537D)
E07 ： Solenoid valve control sensor is open circuit (for MDF-U537 only)
E08 ： Solenoid valve control sensor is short circuit (for MDF-U537 only)
E09 ： Buttery switch OFF with ALARM TEST
E10 ： Compressor temperature is abnormal （for MDF-U537, U537D）

a. Model code setting (for code: 001,002,003)

When temperature sensor is open circuit, display shows alternately E01 with –50℃.

When temperature sensor is short circuit, display shows alternately E02 with +50℃.

b. Model code setting (for code: 002)

When solenoid valve control sensor is open circuit, display shows alternately E07 with
–50℃.
When solenoid valve control sensor is short circuit, display shows alternately E08 with
+50℃.

c. Model code setting (for code: 003)

When TOP lamp is displayed, display shows same as a. in upper compartment.
When BOTTOM lamp is displayed, display shows lower compartment temperature.
When lower compartment temperature sensor is open circuit, display shows alternately
E03 with –50℃.
When lower compartment temperature sensor is short circuit, display shows alternately
E04 with +50℃.

d. Error diagnosis
Self diagnosis of open circuit is done when it is lower than -60℃.

Self diagnosis of short circuit is done when it is higher than +60℃.
E09 is functioned only during ALARM TEST is performed.
In E10 is displayed: When condenser temperature is higher than 85℃, it diagnoses as

abnormal and indicate E10. When condenser temperature is higher
than 100℃ force to turn compressor OFF.
When condenser temperature is lower than 65℃, it diagnoses as

normal and cancel to force compressor turn OFF.
When numbers of error happened simultaneously, error code of smallest number will be
displayed. With exception for MDF-U537D, alternative display of error code and PV,which
is selected compartment internal temperature .
During power failure, display shows alternately E09 with blank.

− 27 −

５．

５． Key lock function

５．５．

In PV display、Keep pushing key over 5 seconds to enter key lock mode displaying with
“L0”.

Push key to 1 ・・・・・key lock ON
0 ・・・・・key lock OFF

then press SET key to memorize set value then return to PV display.

Note） With key lock ON to enter SET mode, but unable to change value.

With key lock ON to perform Function and ALARM TEST, while unable to perform

DEF.

６．

６． Power failure alarm (Buzzer and display isn’t functioned without buttery power

６．６．

supplied)
When power failure is occurred, power failure alarm will be turned on by battery inside units.
During power failure alarm, alarm lamp is blinking, digit display turns off, buzzer sounds
intermittently and remote alarm contact turns ON.
Press BZ key to turn power failure alarm buzzer OFF.
Press BZ key to display PV for 5 seconds.
During power failure alarm, only BZ key (TOP/BOTTOM key for MDF-U537D) is available.

７．

７． Alarm test

７．７．

The function is to check performance (failure) for alarm lamp, buzzer and remote alarm.
In PV display, press ALARM TEST key to blink alarm lamp, to sound buzzer intermittently, to
turn remote alarm contact on (Without time delay). Digital display will be turned off.
During alarm test, only ALARM TEST key is available.
Note: During alarm test, with buttery switch turned OFF to display error code E09.

Displaying error code E09 takes priority over other error codes before ALARM TEST is
performed.

８．

８． Auto return function

８．８．

Function: During setting mode or key lock mode or function mode with any key not pressed

for 90 seconds, value will not be memorized to return to PV mode automatically.

Note: In F09 or F10, auto return function will not be performed.

９．

９． Compressor delay start time

９．９．

During cycle time, normally force to turn compressor OFF after 2 minutes passed compressor
turned off.
When main power is supplied (microcomputer is RESET), changeable to set compressor time
lag for 1 ～15 minutes. (See F05)

− 28 −

１０．

１０．Function mode

１０．１０．

Functions are as follow.
F00 ： To return to PV display
F01 ： To change temperature of high temperature alarm
F02 ： To change temperature of low temperature alarm
F03 ： To change temperature of high temperature alarm

(Applied for lower compartment of MDF-U537D)

F04 ： To change temperature of low temperature alarm

(Applied for lower compartment of MDF-U537D)

F05 ： To set compressor delay start time
F06 ： To input service code (384)
F07 ： To adjust zero for temperature sensor

(Upper compartment sensor for MDF-U537D)

F08 ： To adjust zero for temperature sensor

(Not available for MDF-U333)
(Solenoid valve control sensor for MDF-U537)
(Lower compartment sensor for MDF-U537D)
F09 ： Not available
F10 ： Not available
F11 ： Not functioned. Return to PV display.
F12 ： To display temperature of temperature sensor (per 0.1℃)
F13 ： To display temperature of MDF-U537/U537D compressor protect sensor (per 1℃)
F14 ： To display temperature of temperature sensor (per 0.1℃)

(Solenoid valve control sensor for MDF-U537)

(Lower compartment sensor for MDF-U537D)
F15 ： Not available
F16 ： Not functioned. Return to PV display.
F17 ： To set or check model code

model code 001： MDF-U333
model code 002： MDF-U537

model code 003： MDF-U537D
F18 ： Preset value for second offset performance: -26℃ (for MDF-U537/U537D)
F19 ： Not functioned. Return to PV display.
F20 ： Not functioned. Return to PV display.
F21 ： To set communication ID（000～255）
F22 ： To set communication mode
F23,24,26～29 ： With input each function code, press SET key to sound buzzer 1 second

continuously to maintain input status.

F25 ： To set alarm ring back time
Setting value: 000,010,020,030,040,050,060

Setting method ：：：：

In PV display, keep key pressing over 5 seconds to enter function mode and will be

displayed “F00”. Press key to input required function code then press
SET key again.

F00 ： Not functioned. In F00 displayed, press SET key to return PV display.

− 29 −

F01 ： To set temperature of high temp. alarm performance in the range of +5℃～+15℃.

(initial value : +10℃)

F02 ： To set temperature of low temp. alarm performance in the range of -5℃～-15℃.

(initial value : -10℃)

F03 ： To set temperature of high temp. alarm performance in the range of +5℃～+15℃.
(initial value : +10℃)
Return to PV display except for lower compartment of MDF-U537D.

F04 ： To set temperature of low temp. alarm performance in the range of -5℃～-15℃.

(initial value : -10℃)

Return to PV display except for lower compartment of MDF-U537D.

F05 ： To set compressor delay start time

（performed only when main power supplied or microcomputer reset）

The function is to reduce compressor’s start up failure or breaker’s blown out that

caused by numbers of units simultaneous start up after power failure.

The setting range of time lag is 1～15 minutes. (Initial value is 1 minute on factory

outgoing)
SV before doing factory’s performance test, is 3 seconds or less. Therefore, the time
lag is 0 (3 seconds) when PCB replacement is done in service. It is recommended to
input 1～15 for value when PCB is replaced.

F06 ： Input service code with key and key when F07 and following functions,

except F21, F22 and F25 would be performed. Press SET key to memorize service
code to enter function mode again to perform F07 and following functions.

Service code : 384

Note）Service code is memorized unless input “000” again in ”F06”, or turn power OFF.

(Turn OFF = buttery switch and power supply switch are turned OFF)

Note) After using service code on service, input “000” again in “F06”.

F07 ：To adjust 0 of temperature sensor (setting range: -9.9℃～+9.9℃)
Setting method: In ”Ｆ07” displayed, press SET key to display ”00.0”（initial value）.

Set temperature with key and key and press SET key

again to memorize set value. Input is done by differential value.

Ex） When actual temperature of 1/2h is shown –28.5℃and digital display is

shown -30℃, add +1.5 to value in F07.

Calculation = (-28.5-(-30)) = +1.5

key enables to change only “0” and “-“ in second digit and to change

“0”～”9” in first digit and first decimal place.
key enables to shift the second digit ⇔ the first digit ⇔
the first decimal place⇔the second digit.

− 30 −

F08 ：To adjust 0 of temperature sensor （setting range: -9.9℃～+9.9℃）
In F17: It is functioned in model code 002(MDF-U537), 003(MDF-U537D).
Return to PV display in model code 001(MDF-U333)
Setting method: In ”Ｆ08” displayed, press SET key to display ”00.0”（initial value）.
Set temperature with key and key and press SET key

again to memorize set value. Input is done by differential value.

Ex） When actual temperature of 1/2h chamber is shown –28.5℃and digital

display is shown -30℃, add +1.5 to value in F08.

Calculation = (-28.5-(-30)) = +1.5
key enables to change only “0” and “-“ in second digit and to change

“0”～”9” in first digit and first decimal place.
key enables to shift the second digit ⇔ the first digit ⇔
the first decimal place⇔the second digit.

Ｆ12 ：Temperature of temperature sensor is displayed as per 0.1℃.

From second digit to first decimal point is shown in display.

It is not shown “-“ in display when temperature is lower than -20℃.
(Ex. Actual temperature -35℃ → Display shows 35.0℃)

When temperature is within the range of -19.9℃～-0.1℃, ”-“ is displayed.

Range : -72.0～+83.0℃（±9.9℃）

Ｆ13 ：Temperature of compressor protect sensor is displayed as per 1℃.

Range: -72～+163℃

Ｆ14 ：Temperature sensor (solenoid valve control sensor for MDF-U537, lower compartment

temperature control sensor for MDF-U537D)

Temperature of each sensor is displayed as per 0.1℃
From second digit to first decimal point is shown in display.

It is not shown “-“ in display when temperature is lower than -20℃.
(Ex. Actual temperature -35℃ → Display shows 35.0℃)
When temperature is within the range of -19.9℃～-0.1℃, ”-“ is displayed.
Range : -72.0～+83.0℃

− 31 −

F17 ：Model code setting or checking

001 ：MDF-U333
002 ：MDF-U537
002 ：MDF-U537D

Followings are initial setting values
Internal temp. SV ： -30℃ (for U537D : both compartments)
Key lock mode ： 0 （OFF）
High temperature alarm ： SV+10℃(for U537D : both compartments)
Low temperature alarm ： SV-10℃(for U537D : both compartments)
0 adjustment：+0℃（for temperature sensor）

Compressor start delay time ： 1 minute

Communication ID ： 000
Communication mode ： 000

Alarm ring back time ： 030 (30 minutes)
Set model code as MDF-U537, MDF-U537D to activate compressor protect function.

F21 ： To set serial communication ID.
Input range: 000～255 （000 means that communication is OFF）

F22 ： To set serial communication mode.

rd

Control mode （3

digit） 0 ： Local （initial value）

1 ： Remote

nd

Baud rate （2

digit） 0 ： 2400bps （initial value）

1 ： 4800bps

2 ： 9600bps

st

1

digit is not used.

Note） Set control mode as “remote” unable to change SV and to activate defrosting.

F25 ： To set value for alarm recovery (ring back) time.
Input value: 000,010,020,030,040,050,060 (In 000, recovery function is OFF)

１１．

１１．Differential （COMP. ON/OFF point on program）

１１．１１．

COMP ON permit ： Activate at +0.0℃ higher than SV
COMP OFF： Activate at -0.6℃ lower than SV

− 32 −

１２．

１２．Offset value

１２．１２．

The function is to correct differential value between temperature of temperature sensor and
of internal 1/2H (centre of chamber).
Initial offset
001 (MDF-U333): Shift –1.5℃from temperature of temperature control sensor (PV)
002 (MDF-U537): Shift +1.0℃from temperature of temperature control sensor (PV)
(For upper, lower compartment)
003 (MDF-U537D): Shift +0.0℃from temperature of temperature control sensor (PV)
(For upper, lower compartment)
Second offset
001 (MDF-U333): None
002 (MDF-U537):-18℃≧SV≧-25℃--- shift –0℃from PV (For upper, lower compartment)

-26℃≧SV -- shift +1.0 from PV (For upper, lower compartment)
003 (MDF-U537D):-18℃≧SV≧-30℃--- shift PV-2.4+(-18-SV)÷5 (For upper compartment)

-30℃＞SV --- shift –0℃from PV (For upper compartment)
*Note) For lower compartment, add 0℃ to PV.

１３．

１３．Display offset

１３．１３．

In display, temperature that is lower than SV is shown for a little time. With this case, display
offset –0.5℃should be done. (Round off numbers to the first decimal point)

１４．

１４．Remote alarm

１４．１４．

During normal operation … … … Remote alarm contact is OPEN
During alarm or power failure … … … Remote alarm contact is CLOSE

１５．

１５．Others

１５．１５．

MDF-U537: In case of : -18℃≧SV≧–25℃ with PV-SV+5℃≧0

Solenoid valve is: Forced to turn OFF

MDF-U537: In case of : PV-(SV-0.6℃)≧0 with PV

TOP

- PV

BOTTOM

-1＞0

Solenoid valve is: Forced to turn OFF

(In PV-(SV-0.6)＜0, quit to be forced to turn OFF)

− 33 −

−

Wiring diagram



−34

−

−35

−



−36

−

Circuit diagram

<Main PCB>




−37

Components on PCB

<Main PCB>

−38−

Test data

･ＭＤＦ－Ｕ３３３ Pull down 40

･ＭＤＦ－Ｕ３３３ Pull up 40

･ＭＤＦ－Ｕ３３３ Cooling unit pressure 41

･ＭＤＦ－Ｕ３３３ Power consumption 41

･ＭＤＦ－Ｕ３３３ Temperature uniformity and fluctuation 42

･ＭＤＦ－Ｕ５３７ Pull down 43

･ＭＤＦ－Ｕ５３７ Pull up 43

･ＭＤＦ－Ｕ５３７ Cooling unit pressure 44

･ＭＤＦ－Ｕ５３７ Power consumption 44

･ＭＤＦ－Ｕ５３７D Pull down 45

･ＭＤＦ－Ｕ５３７D Pull down 45

･ＭＤＦ－Ｕ５３７D Pull up 46

･ＭＤＦ－Ｕ５３７D Cooling unit pressure 47

･ＭＤＦ－Ｕ５３７D Power consumption 47

･ＭＤＦ－Ｕ５３７/D Temperature uniformity and fluctuation 48

−39−

40

ＭＤＦ－Ｕ３３３ Pull down

AT35℃，noload

30

20

10

0

-10

Internal temperature [℃]

-20

-30

-40

0246810

Time scale [H]

50Hz 60Hz

ＭＤＦ－Ｕ３３３ Pull up

20

10

0

-10

-20

Internal temperature [℃]

-30

-40
02468

Time scale[H]

AT35℃，無負荷

−40−

1600

1400

1200

1000

Pressure ［kPa］

ＭＤＦ－Ｕ３３３　Cooling unit pressure

Pd(50Hz) Ps(50Hz) Pd(60Hz) Ps(60Hz)

AT35℃，no load

800

600

400

200

0

0 1 234567

Time scale ［ｈ］

ＭＤＦ－Ｕ３３３　Power consumption

W(50Hz) W(60Hz)

250

AT35℃，no load

200

150

100

Power consumption［Ｗ］

50

0

0 1 234567

Time scale ［ｈ］

−41−

ＭＤＦ－Ｕ３３３

Temperature uniformity and fluctuation

（Test condition）
Mains : 1φ100V50/60Hz
AT : 35℃
SV ： -25℃・-20℃・-30℃
No load Measure with type T sensor

Measuring point：Center point of each container

１

２

３

４

５

（１）．ＳＶ＝－２５℃

Measuring point

Top -21.8

1

2

Middle -24.3 ± 2.0

3( 1/2 center air)

4

Bottom -24.2

Uniformity

5

Max./Min -21.8/-24.6

Range(deg) 2.8(±1.4)

Temperature(℃） Fluctuation(℃）

-23.2

-24.6

（２）．ＳＶ＝－２０℃

Measuring point

Top -17.1

1

2

Middle -19.1±2.6

3( 1/2 center air)

4

Bottom -19.0

Uniformity

5

Max./Min -17.1/-19.4

Temperature(℃） Fluctuation(℃）

-18.3

-19.4

Range(deg) 2.3(±1.15)

（３）．ＳＶ＝－３０℃

Measuring point

Top -26.3

1

2

Middle -29.3 ±1.7

3( 1/2 center air)

4

Bottom -29.1

Uniformity

5

Max./Min -26.3/-29.4

Temperature(℃） Fluctuation(℃）

-28.1

-29.4

Range(deg) 3.2(±1.6)

note）These data are reference only.

−42−

ＭＤＦ－Ｕ５３７　Pull down

50Hz 60Hz

40

30

20

10

0

-10

Internal temperature［℃］

-20

-30

-40

0246810 12

Time scale ［H］

AT 35℃，no load

ＭＤＦ－Ｕ５３７ Pull up

AT 35℃，no load

20

10

0

-10

-20

Internal temperature ［℃］

-30

-40

0246810

Time scale ［H］

−43−

2000

1500

1000

Pressure [kPa]

500

0

0246810 12

ＭＤＦ－Ｕ５３７Cooling unit pressure

Pd(60Hz) Ps(50Hz) Pd(60Hz) Ps(60Hz)

AT 35℃，no load

Time scale [H]

ＭＤＦ－Ｕ５３７ Power consumption

W(50Hz) W(60Hz)

300

AT 35℃，no load

200

100

Power consumption[W]

0

0246810 12

Time scale [H]

−44−

40

ＭＤＦ－Ｕ５３７Ｄ Pull down

30

20

10

-10

Internal temperature［℃］

-20

-30

-40

AT35℃，50Hz，no load

Top chamber
Bottom chamber

0

0246810 12

Time scale［H］

40

30

20

10

-10

Internal temperature［℃］

-20

-30

-40

ＭＤＦ－Ｕ５３７Ｄ Pull down

AT35℃，60Hz，no load

Top chamber
Bottom chamber

0

0246810 12

Time scale［H］

−45−

ＭＤＦ－Ｕ５３７Ｄ Pull up

30

AT35℃，no load

20

10

0

-10

Top chamber

Internal temperature［℃］

-20

-30

-40

0246810

Time scale［H］

Bottom
chamber

−46−

2500

2000

1500

1000

Pressure[kPa]

500

0

0246810 12

ＭＤＦ－Ｕ５３７Ｄ　Cooling unit pressure

Pd(50Hz) Ps(50Hz) Pd(60Hz) Ps(60Hz)

AT35℃，no load

Time scale [H]

ＭＤＦ－Ｕ５３７Ｄ　Power consumption

W(50Hz) W(60Hz)

500

AT35℃，no load

400

300

200

Power consumption[W]

100

0

0246810 12

Time scale[H]

−47−

ＭＤＦ－Ｕ５３７ / Ｄ　temperature uniformity and fuluctuation

Mains ： 100V50Hz
AT ： 35℃
SV ：-20℃・-25℃・-30℃
No load Mesure with type T sensor
Measureing point : Center point of each container /chamber

MDF-U537

１

２

３

４

５

６

７

《 MDF-U537 》

Measuring point

Uniformity ［deg.］　　

Fluctuaation［℃］　

MDF-U537D

１

２

８

SV -20℃ SV -25℃ SV -30℃

1

2
3
4
5
6
7
8

-19.7 -24.6 -30.8

-20.9 -25.7 -31.7

-21.1 -25.4 -31.7

-19.6 -24.7 -29.4

-19.9 -24.4 -29.6

-21.2 -25.1 -30.7

-18.7 -22.8 -27.8

-19.9 -24.1 -29.7

2.5 2.6 3.9

±2.0 ±1.4 ±1.5

３

５

６

７

８

４

９

《 MDF-U537D 》

Measuring point

1

2
3
4

Uniformity ［deg.］　　

Fluctuaation［℃］　

5
6
7
8
9

Uniformity ［deg.］　　

Fluctuaation［℃］　

note)These data are reference only

SV -20℃ SV -25℃ SV -30℃

-17.7 -22.4 -27.4

-19.9 -25.1 -30.1

-18.8 -24.9 -30.8

-19.8 -24.9 -30.2

2.2 2.7 3.4

±3.1 ±2.1 ±0.9

-22.4 -25.8 -29.8

-21.3 -25.3 -29.5

-20.5 -25.8 -30.4

-17.9 -23.3 -28.1

-21.7 -26.2 -30.4

4.5 2.5 2.3

±3.2 ±2.6 ±1.3

−48−

＜Memorandum＞

Parts layout

ＭＤＦ－Ｕ５３７

ＭＤＦ－Ｕ５３７

ＭＤＦ－Ｕ５３７ＭＤＦ－Ｕ５３７

Inside of control panel

Electrical parts on top

Top view of product Access port for recorder wires

Connecter for buzzer

Connecter for display P.C.B.

Back view of product

Door latch

Inner parts
of door latch

Remote alarm terminal Breaker switch

・Temperature control sensor (MDF-Ｕ５３７)
・Temperature control sensor
　　　　　for upper chamber (MDF-Ｕ５３７D)

・Solenoid valve control sensor (MDF-Ｕ５３７)
・Temperature control sensor
　　　　　for lower chamber (MDF-Ｕ５３７D)

Connecter for tenperature recorder power sourece

−49−

User’s manual

・ This section is extracted and printed from User’s Manual.

・ If you find out “Refer to page ●●” in them, this page means not page in service manual

but page in the lower corner of each page in the extract from user’s manual.

This page number is not corresponded with serial number in Service manual.

−50−

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22

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28

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