MS99

Manostar switch
List ofproducts

WO81

MS99
Fine differential pressure switch

30 V DC and lower rated
voltage
specification only

• Wide setting range due to employment of multi-start thread.
WO71

FR51A

• Standardization of the contact has eliminated the need to specify theRoHS

normal load and fine load.
• High accuracy has been achieved.
• Exchange of base makes it possible to connect various pipes (forexchangeable base type only).

MS99• Products compatible with EC directive (CE marking) are also available (30V DC and lower rated voltage specification).

MS99S

MS61A-RA

QDP33

EMD8A

EMD7

EMT1

EMTGP1Model MS99 V

EMT1H

Model MS99 C(Integrated base type)(Exchangeable base type)

EMT6

EMP5A

EMRT1

Product code

HWS15A<Main application fields>

Accessories
Application

Precautions
Maintenance• General factory management
equipment• Negative pressure for dust
collector/differential pressure of airconditioner• Filter pressure loss management• Precision machine manufacturingline• Building air conditioning control
equipment<Usage>• Detection of clogging of air filter• Room pressure measurement in aclean room• Measurement of clogging of bugfilter• Measurement of dynamic pressure
at ventilation/exhaust device*(Refer to pages 114 to 117)

35MS99Ｌ ＶPressure range code500

Ｄ Ｖ(Example)
Opening/closing
capabilityMounting
orientation
Unit
Range
Base
Scale setting◆When making an inquiry or placing an order, specify the above product code.

NoneStandard specificationＬ

30 V DC and lower rated voltage
specification

ＶＨ

Upright

ＤＥPa

HorizontalkPa

Maximum scale value

ＶC

Integrated type

ＨＬUpper limit setting

Exchangeable typeLower limit setting

MS99

Manostar switchMS99List ofproducts

Specifications
Model

Integrated base type, forupper limit setting

Integrated base type, for lower Exchangeable base type, forlimit setting
upper limit setting

MS99HVMS99LV

Pressure unit

Pa, kPa

Pressuremeasurement
methodDifferential pressure method

Pressure-receiving
element

Diaphragm

Contact material

Silver alloy/gold plating

Measured gas

Air and noncorrosive gas (liquid cannot be measured)

Pressure setting
methodSetting by dial with scale

Mounting orientation

Upright or horizontal

Operating ambient
temperature−10°C to +60°C (no freezing allowed)

Operating ambient
humidity

90% RH or below (no condensation allowed)

Exterior material

Model V
Model C

Durable vibration

5 to 10 Hz, amplitude of 10 mm,
10 to 50 Hz, acceleration of 39 m/s2 (two hours each forthree axial directions)

Durable impact

100 m/s2 (six times each for three axial directions)

Insulation resistance

Between terminal and case: 20 MΩ or higher (500 V DCmegger)

Withstand voltage

Between terminal and case: 1500 V AC, 50/60 Hz, for one
minutePressure range
code

MS99HC
Compatible pipe

Pressure range

Mounting orientation*It is necessary to specify theorientation at the time oforder placement for allranges.

M4 (mountable terminal: outer diameter of φ8 or below)
Indicating high-pressure side and low-pressure side with“H” and “L” marks, respectively, at the piping connection
base part.
Model V Approx. 170 g
Model C Approx. 190 g
None (cable clamp is separately sold)
UL standard
UL and C-UL recognition component
Requirement standard No.......... UL508
File No........................................ E240648*Acquired as open-type enclosure.
RoHS directive
Equivalent to IP54 (at time of acquisition of cable clamp)

Mass
AccessoriesConforming
standards

Protection level
Cable clamp
mounting screw size

M15 P=1

Repeatability

Maximum operating Pressure-receiving instrument body and pressurereceiving element
pressure difference element material

20–120 Pa±5.0 Pa±2.0 Pa

25.0 Pa

20–200 Pa±9.0 Pa±2.0 Pa

25.0 Pa

300 D

30–300 Pa±13.5 Pa

±3.0 Pa

30.0 Pa±22.5 Pa

±5.0 Pa

45.0 Pa±45 Pa

±10 Pa70 Pa±0.135 kPa±0.030 kPa

0.300 kPa

50–500 Pa
100–1000 Pa

3E

0.3–3 kPa

Horizontal
orUpright

5E

0.5–5 kPa

±0.225 kPa±0.050 kPa

0.450 kPa

10 E1–10 kPa±0.45 kPa

±0.10 kPa

0.70 kPa

30 E

3–30 kPa±1.35 kPa

±0.30 kPa

3.00 kPa

30 V DC
Standard load

100 V AC
250 V AC

Minute load

30 V DC
125 V AC

Specifications
Contactconfiguration
SPDT (single-poledouble-throw)
Electric service life
100,000 times ormore

Resistance load
0.8 A
5A

Induction load
150 mATime constant

60 mA

Power factor

7 ms
0.65A―

100 mA―Opening/closing capability [30 V DC and lower rated voltage specification]
LoadStandard load
Minute load

！

MS99S

MS61A-RA

QDP33

EMD7

EMT1

EMTGP1

Silicone rubber
20 kPa

EMT1H

50 kPaRated voltage

Specifications

30 V DC

Contact configuration
SPDT (single-pole doublethrow)
Electric service life
100,000 times or more

Resistance load
0.8 A
100 mA

Induction load
150 mATime constant

7 ms―Rating certified withsafety standard (UL)
[Standard specification]

EMP5A

Rating125 V DC–0.5 A RES
250 V AC–5 A RES

EMRT1Rating certified withsafety standard (UL)

HWS15A[30 V DC and lower rated
voltage specification]
Rating30 V DC–0.5 A RES*To enhance the contact reliability of the contact under minute load condition, gold plating is applied to the contact surface. If the instrument is used with a voltage orcurrent exceeding the rating at the time of use of minute load, the gold plating will be broken and the contact reliability of the contact under minute load condition will bedegraded.
Under minute load conditions, do not use such a product that has been used any number of times under normal load conditions.

CautionMS99

EMT6Opening/closing capability [standard specification]
Rated voltage

FR51A

10 kPa◆For use environment, refer to page 118.

LoadWO71(Refer to page 118)

200 D
500 D

WO81

EMD8A
Withstanding pressures ofScale setting
accuracy(at 23°C)

120 D

1000 D

MS99LC

Model V• Vinyl pipe or rubber pipe (inner diameter of 4 mm)
Model C• Vinyl pipe or rubber pipe (inner diameter of 6 mm)
Base for resin vinyl pipe (already mounted on instrument)• Metallic pipe (outer diameter of 6 ± 0.1 mm)
Separately sold base for metallic pipe is necessary.
• Hard tube (outer diameter 6 × inner diameter 4 mm)
Separately sold base for metallic pipe and inner sleeveset (refer to page 95) or push-in joint is necessary.

Terminal screw size
Base polarity

Polycarbonate
Polycarbonate and polyamide

Exchangeable base type, forlower limit setting

Accessories
Application

Precautions
Maintenance• In an induction load circuit, such as a relay, there is a possibility of contact problems with a contact due to back electromotive force or inrush current at thetime of opening or closing. Therefore, be sure to insert a protective circuit for surge absorption, such as a diode and varistor.
• If silicone gas or organic gas is contained in the measured gas, such an organic substance that may lead to defective contact of a contact that is caused byarc energy at the time of contact opening/closing. If offensive gas is contained in the measured gas, malfunctioning due to defective contact of a contact orcorrosion of the internal mechanism may occur. If any of the above gases exist in the measured gas or surrounding environment, discuss the use of a modelwith the built-in lead switch MS61A-RA, whose contact is less subject to the external atmosphere.

36

MS99

Manostar switch
List ofproducts

WO81

MS99
External dimension drawingModel MS99 V (integrated base type)

WO71

0WHUPLQDOVFUHZ
0RXQWDEOHWHUPLQDORXWHUGLDPHWHURIĳRUEHORZîĳ&DEOHFODPSPRXQWLQJKROH
Ｍî0RXQWLQJKROH&RYHUPRXQWLQJVFUHZ

18FR51A
32190
10078MS99S

36MS9940MS61A-RA
11îĳRU03578

φ4.5

6FDOH

48
53

8.5

90±0.3

QDP33

EMD8A

3DQHOFXWWLQJ
EMD7EMT1

Model MS99 C (exchangeable base type)36

EMTGP1&DEOHFODPSPRXQWLQJKROH0î0WHUPLQDOVFUHZ0RXQWDEOHWHUPLQDORXWHUGLDPHWHURIĳRUEHORZîĳ0RXQWLQJKROH&RYHUPRXQWLQJVFUHZ18EMT1H

210078

1EMT690111

3φ7

EMP5A

EMRT13578

246FDOH
485324

HWS15A

Application
40

Precautions

90±0.3îĳRU0

Accessories

Maintenance

3DQHOFXWWLQJ！
Caution37

Base tightening torque: 1 N·m
Terminal screw tightening torque: 0.7 to 1.0 N·m
Do not tighten to a torque that exceeds the specified value because doing sobreaks the instrument body. (Refer to page 120)

MS99

Manostar switch
MS99

List ofproducts

Overview of structure

WO81

1978

Number

261011435Name

1Cover2

Main frame

3Base

4Diaphragm

5Mounting plate

6

Fixed contact

7Movable contact

8Terminal

WO71

FR51A

MS99

9Dial

10

Low-pressure side base

11High-pressure side base

MS99S

MS61A-RA

Mounting orientation and range

It is necessary to specify the orientation at the time of order placement for all ranges.

7KHLQVWUXPHQWFDQEHPRXQWHGRQWKHPRXQWLQJVXUIDFHLQDQDUELWUDU\PDQQHU

90°

HEO

QDP33

EMD8A

8Q
X+RUL]RQWDO

EOH
VD

8Q
XV
D

8SULJKWSODQH
5°5° 8SULJKW

5°5°0°

EMD7+RUL]RQWDOSODQH

EMT1

EMTGP1Accessories dedicated to MS99

RoHS

Mounting plate

Cover

Cable clamp holder(Auxiliary item)

Dedicated toV type and Ctype(Auxiliary item)

EMT1H(Auxiliary item)

EMT6

EMP5A
This is already installed at the time of purchase of theinstrument.
This cannot be used for Model MS99S.

Item number

ADPL99-01

This is already installed at the time of purchase of theinstrument.

MaterialItem number

Aluminum/steel

This is already installed at the time of purchase of theinstrument.

Material

TCA-99Polycarbonate/steel

Item number

ADPA-MS99

Material

Polycarbonate

Cable clamp (Ohm Electric Co., Ltd.)[External dimension attime of mounting]

Mounting hole diameter: φ15
Mounting screw: M15 P=1[Schematic figure of mounted cable clamp]
Only by changing the orientation of the transparent cover, it ispossible to change the wiring direction.

(111.5)

3！

Caution

φ2-4
φ3-5
φ5-7

HWS15A

Accessories
Application

2Precautions
MaintenanceMaterial

Nylon 66
PolypropyleneNBR(22)

Item number

OA-W15M-04
OA-W15M-05
OA-W15M-07

Compatible electric
wire diameter

1EMRT118

At time of mounting of cable clamp, protection level isequivalent to IP54.

• In mounting of the cable clamp to the instrument body, the supplied locknut is not used.
• When extracting the wire in the base direction on Model MS99 C (exchangeable base type), the installation is disabled because the base andthe cable clamp interfere with each other.

38

MS99

Manostar switch
List ofproducts

WO81

MS99
Accessories for C type

RoHSVT base

VR base(Auxiliary item)

WO71

High-pressure side

Low-pressure side

FR51A
Item number

KGA99VT

MS99

MS99S

Material

Item number

Polyamide

Material

KGA81VR-H

A vinyl pipe or rubber pipe with an inner diameter of 6 mm can beconnected. This is already installed at the time of purchase of theinstrument.

High-pressure side

Material

KGA81VR-L

Brass

This serves as an elbow whose tube mounting part rotates. Avinyl pipe or rubber pipe with an inner diameter of 6 mm can beconnected.

PT baseMS61A-RA

Item numberBrass

PR baseLow-pressure side

High-pressure side

Low-pressure sideQDP33

EMD8A

Item number

KGA81PT-H

EMD7

Material

PBT/brass

Item number

KGA81PT-L

Material

PBT/brass

The tube mounting part is a push-in joint. For piping, use theseparately sold tube (refer to page 112) or a tube compatible with JIS
B 8381-1. (Connectable tube outer diameter: 6 mm)

Item number

KGA81PR-H

Material

PBT/brass

Item number

Material

KGA81PR-L

PBT/brass

The tube mounting part is a rotary elbow push-in joint. The piping is
the same as that for the PT base. (Connectable tube outer diameter: 6mm)

EMT1

MT baseEMTGP1High-pressure side

MR baseLow-pressure side

High-pressure side

Low-pressure side

EMT1H

EMT6

Item number

KGA81MT-H

EMP5A

EMRT1

HWS15A

Material

Brass

Item number

Material

KGA81MT-L

Brass

Item number

Material

KGA81MR-H

Brass

Item number

Material

KGA81MR-L

Brass

A metallic pipe, such as copper pipe and aluminum pipe with anouter diameter of 6 ± 0.1 mm, can be connected. However, forstainless steel pipe, use an MTW base. When connecting with aplastic pipe (outer diameter 6 mm × inner diameter 4 mm), remove
the brass sleeve and use the separately sold resin inner sleeve set(XIN6×4; refer to page 111).

This serves as an elbow whose tube mounting part rotates.
The piping material is the same as that of the MT base. Whenconnecting with a plastic pipe (outer diameter 6 mm × innerdiameter 4 mm), remove the brass sleeve and use the separately
sold resin inner sleeve set (XIN6×4; refer to page 111).

MTW base

Adapter for rear face piping

High-pressure side

Low-pressure side

High-pressure side

Low-pressure side

Accessories
Application

Precautions
MaintenanceItem number

KGA81MTＷ-H-S

Material

Stainless steel

Item number

KGA81MTＷ-L-S

Material

Stainless steel

This is used to connect a stainless steel pipe with an outer
diameter of 6 ± 0.1 mm.

Item number

KGA81FBA-H

Material

Brass

Item number

KGA81FBA-L

Material

Brass

When a rotary base is used, it ispossible to provide a step so thatpipes do not contact each other evenwhen they cross each other. (Figureon the right)$GDSWHUIRUUHDUIDFHSLSLQJ

39

MS99

Manostar switch
MS99

List ofproducts

Example of mounting of type C base

WO81

WO71

FR51A

MS99

MS99S

MS61A-RA

QDP33

VR basePT basePR base
EMD8A

EMD7

EMT1

EMTGP1

EMT1H

MT baseMR baseMTW base
EMT6

EMP5A

EMRT1

HWS15A

Accessories
Application！
Caution•Even when the bases are exchanged with each other, the high-pressure side and low-pressure side polarities cannot be changed. The basepolarities are indicated with an “H” mark on the high-pressure side and an “L” mark on the low-pressure side at their respective base mountingparts.
• Base tightening torque: 1 N·m Sealing cap tightening torque: 0.5 N·m
Do not tighten to a torque that exceeds the specified value because doing so breaks the instrument body. (Refer to page 120)

Precautions
Maintenance

40MS99

Manostar switch
List ofproducts

MS99

WO81

Protection of switch contact

WO71○To reduce the noise generated at the time of opening/closing of the load andlengthen the service life of the contact by decreasing the generation of nitricacid gas and carbide, a contact protection circuit is used. However, it will havean opposite effect if it is not used correctly.

○When a contact protection circuit is used, the operation time of theload may be slightly delayed. Representative examples of a contact
protection circuit are provided below.

Representative examples of a contact protection circuit
FR51A

Applicable powersourceCircuit example

DCU

R C

MS61A-RA

3RZHUVRXUFH

MS99S

3RZHUVRXUFH

MS99,QGXFWLRQORDG,QGXFWLRQORDG

Varistor
methodC/R method○○○○This method prevents a voltage equal to or exceeding the varistor’s limit voltage frombeing applied between the contacts. In this method, the return time of the induction loadon the relay is slightly delayed.
○From the selection materials from varistor manufacturers, select a varistor with a ratingthat matches the power voltage and load capacity.

○○In this method, the operation/return time is slightly delayed if the load is an induction
load such as relay.
○The CR values should be around C: 0.5 μF/A and R: 1.0 Ω/V with respect to the contact
current and contact voltage, respectively, as a guide. However, as these values varydepending on the property of the load and other conditions, check the values throughexperiment and select an appropriate model.

×○In this method, the back electromotive force of the induction load is canceled by the load
resistance through a diode to prevent high voltage from being applied between contacts.
In this method, the return time of induction load is more delayed compared to the varistor
type and CR method.
○Select a diode whose rating current is equal to or greater than the load current and whose
reverse breakdown voltage is 10 times the power voltage or greater.

×○The diode method is effective when the return time of the induction load on the relay isexcessively delayed. Select a Zener diode whose Zener voltage is almost equal to thepower voltage as a guide. However, if the load increases, a Zener diode whose reverse
surge power is great is required. Therefore, this method has a limit, and attention needs
to be paid when selecting this method.

EMD73RZHUVRXUFH

EMD8A

Diode method

3RZHUVRXUFH

QDP33,QGXFWLRQORDG,QGXFWLRQORDG

Diode+Zener diodemethod○○

Points to note when applying/selecting circuit

AC

EMT1C

EMTGP13RZHUVRXUFH

Examples of bad contact protection circuit,QGXFWLRQ
ORDG

EMT1H

EMP5A

EMRT1

HWS15A

Accessories
Application

Precautions
Maintenance

41

3RZHUVRXUFH

Condenser method
CEMT6○This method is very effective for extinction of an arc at the time of release of the contact,
but the charging current flows to the condenser when contacting the contact, making thecontact likely to be welded and shortening the contact service life.

,QGXFWLRQORDG○This method is very effective for extinction of an arc at the time of release of the contact,
but short-circuit current in power storage capacity stored in the condenser flows whencontacting the contact, making the contact likely to be welded and shortening thecontact service life.

MS99

Manostar switch
MS99

List ofproducts

Notes on contact material
To enhance the contact reliability of the contact under minute load condition, gold plating is applied to the contact surface. If theinstrument is used with a voltage or current exceeding the rating at the time of use of minute load, the gold plating may break, andthe contact reliability of the contact under minute load conditions may degrade.

！

Under minute load conditions, do not use such a product that has been used any number of times under normal load conditions.

WO81

WO71

FR51A

CautionConfiguration of switch contact

MS99
Differentialpressure
increases.

○ The contact configuration of this instrument is as shown on the right.
○ The state in which the differential pressure (pressure) is not applied to the instrument isreferred to as normal condition.
○ In the normal the condition, the section between contact 1 (COM.) and contact 2 (N.C.) isclosed, and the section between contact 1 (COM.) and contact 3 (N.O.) is open.
○ When the differential pressure increases and reaches the set pressure, the contact isswitched, the section between contact 1 (COM.) and contact 2 (N.C.) turns to be open, and thesection between contact 1 (COM.) and contact 3 (N.O.) turns to be closed.

6HW
SUHVVXUH

MS61A-RA
2SHUDWLQJ
SUHVVXUHGLIIHUHQFH

Upper limit setting and lower limit setting

MS99S'LIIHUHQWLDOSUHVVXUH

GHDGEDQG
The pressure at which the electric contact of the switch is triggered as the differential pressure
5HVHW
(pressure) applied to the instrument has increased from zero is referred to as the set pressure.
SUHVVXUH
Then, the pressure at which the contact has returned to the former state as the differential
pressure has decreased from the use condition at a pressure greater than the set pressure andthe electric contact has been triggered is referred to as the reset pressure.
7LPH
The set pressure and reset pressure mentioned above are not the same values but are slightly)LJXUHIRUH[SODQDWLRQRI
different from each other. This difference is referred to as the operating pressure difference (deadRSHUDWLQJSUHVVXUHGLIIHUHQFHband).
This instrument has two variations: one with the scale of setting dial set to the set pressure; and the other with the scale set to the resetpressure.
This instrument with the scale set to the set pressure is referred to as the instrument for upper limit setting and the instrument with the scale
set to the reset pressure is referred to as the instrument for lower limit setting.

QDP33

EMD8A

EMD7

EMT1

When the setting pressure is set to 1 kPa in the pressure range of 1 to 10 kPa as an example (the operating pressure difference is assumed
to be 0.7 kPa)
Setting dial scale adjustment

Instrument for upper
limit setting

Adjustment is made by means of
set pressure.

When the differential pressure increases, the section between 3 (N.O.) and 1(COM.) closes at 1 kPa. Then, when the differential pressure decreases, thesection between 3 (N.O.) and 1 (COM.) opens at 0.3 kPa.

EMT1H

Instrument for lower
limit setting

Adjustment is made by means ofreset pressure.

When the differential pressure increases, the section between 3 (N.O.) and 1(COM.) closes at 1.7 kPa. Then, when the differential pressure decreases, thesection between 3 (N.O.) and 1 (COM.) opens at 1 kPa.

EMT6！

Contact action

EMTGP1

Scale setting

It is not possible to change from the upper limit setting to the lower limit setting and vice versa.

CautionReset time
Reset time refers to the time it takes to reach the reset pressure (the electric contact is reset) when the differential pressure is suddenly
reduced to zero from the set pressure. In this instrument, the reset time is approx. 3 seconds at 20 Pa and approx. 1 second at 50 Pa andgreater. (However, the reset time is for the instrument body only, not including the pipe.) Therefore, a response faster than this time isimpossible.

EMP5A

EMRT1

HWS15A

Contact rating
If the contact capacity in the specification is exceeded, additionally connect the secondary relay. In general, the smaller the voltage andcurrent are, the longer the contact service life is. A Manostar switch cannot directly shut off a circuit whose voltage exceeds 250 V AC.

Accessories

Measured gas

Application

If offensive gas (nitric acid, hydrogen sulfide, sulfurous acid, ammonia, chlorine, etc.) is contained in the measured gas, malfunctioning due
to defective contact of a contact or corrosion of the internal mechanism may occur. If the measured gas is highly humid, nitric acid may be
produced due to an arc at the time of opening/closing of the contact, which may lead to similar defective contact or malfunctioning. Therefore,
avoid the use of highly humid measured gas.
If the measured gas contains silicone gas generated from silicone (oil, grease, filler, etc.), silicone oxide may be generated and accumulated
at the contact due to an arc at the time of opening/closing of the contact, which may lead to defective contact of a contact. Therefore, remove
the silicone gas generation source or implement arc suppression measures.

Precautions
Maintenance42

Warranty■Warranty period
The warranty period for our product is one (1) year from delivery to the location specified by the orderer who makes a direct transaction
with us.

■Scope of warranty
If any failure or defect attributable to us becomes clear during the above warranty period, we will repair the product or supply asubstitute product free of charge. However, even during the warranty period, we will exclude the product from the scope of the warranty
if the failure or defect corresponds to any of the following:(1) The failure or defect was caused by an unreasonable condition, environment, handling, or usage not mentioned in theinstruction manual, specifications, and our product catalog.
(2) The failure or defect was caused by a factor other than our product.
(3) The failure or defect was caused by a modification or repair conducted by a party other than us.
(4) The failure or defect was caused by an event that could not be foreseen at the scientific and technical levels at the time ofproduct shipment from us.
(5) The failure or defect was caused by an external factor not attributable to us, such as acts of God and disasters.
Please note that the warranty mentioned here means the warranty for our individual product, and damage provoked by a failure or
defect of the product is excluded from the scope of the warranty.
*This warranty is valid only in Japan.

Application and usage
Our products are designed and manufactured as general-purpose instruments for general industries.
Therefore, our products are not intended for the following uses, and our products used in such a manner are outside the scope ofapplication.
(1) Equipment that is anticipated to greatly affect lives and properties, such as nuclear power generation, aviation, railways, marine
vessels, vehicles, and medical devices(2) Utilities that include electricity, gas, and service water(3) Use in outdoor locations and under similar conditions or environments other than those stipulated in the instruction manual(4) Usage to which considerable safety consideration and attention equivalent to (1) and (2) above need to be given

Service■Scope of service
Because the product price does not include service expenses, such as the dispatch of engineers, we will separately charge for theexpenses in the following cases:(1) Instruction for installation and adjustment and a witnessed test run(2) Maintenance inspection, adjustments, and repairs(3) Technical guidance and technical education(4) Witnessed inspections of products at our factory<<Note>> The product specifications and information in this catalog are subject to change without prior notice for product improvement orother reasons.

●For order placement, contact

Generalagent

Manostar Shop Co., Ltd.

1-2-3 Nishishiriike-cho, Nagata-ku, Kobe City, Hyogo 653-0031
TEL. +81-78-621-7000 FAX. +81-78-621-7788

Manufacturer

Yamamoto Electric Works Co., Ltd.

1-2-3 Nishishiriike-cho, Nagata-ku, Kobe City, Hyogo 653-0031
TEL. +81-78-631-6000 FAX. +81-78-631-6020

SEPTEMBER 2021 YAMAMOTO ELECTRIC WORKS CO., LTD., JAPAN