2.4 GHz Band Wireless Unit
SWL31-ETMC
SWL31-R4ML

User's Manual(Hardware Version)
Thank you for purchasing our 2.4 GHz Wireless Unit (hereinafter called "Wireless Unit").
For using the Wireless Unit correctly and safely, at first please read this manual carefully
before using it to understand sufficiently its functions and performance.

Cautions
1. Do not copy this user's manual without permission.
2. Please note that descriptions in this manual may be changed without prior notification.

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1. SAFETY PRECAUTIONS(Please be sure to read them before using the product.)
Please carefully read this manual before using the product and pay full attention to safety in order tohandle the product correctly.
Precautions given in this manual relate only to this product.
In this "1. SAFETY PRECAUTIONS," the safety precautions are ranked as "WARNING" and"CAUTION."WARNING

Indicates that incorrect handling may cause hazardous
conditions, resulting in death or severe injury.
Indicates that incorrect handling may cause hazardous

CAUTIONconditions, resulting in moderate or minor injury or only
material damage.

Note that the CAUTION level may lead to serious consequences according to the circumstances.
Be sure to follow the instructions of both levels since they are important to personal safety.
Please be sure to pass this manual on to the end users.
In addition, please keep it in a safe place so that you can read it when needed.

[WIRING PRECAUTIONS]WARNING● Be sure to block the power supply externally for all phases before wiring, otherwise an electric
shock or product damage may occur.

CAUTION● Check the rated voltage and terminal layout of the product and correctly execute wiring for theterminal block. A wrong rated power supply or wrong wiring may cause fires or breakdowns.
● Be careful not to let foreign matter such as sawdust or wire chips get inside the product. Fires,
breakdowns and malfunctions may occur.

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[DESIGN PRECAUTIONS]WARNING● An external safety circuit shall be installed to this product so that the whole system operates atthe safety side, even if an abnormality of an external power supply has an abnormality, or abreakdown of this product. Erroneous output and malfunctions may cause an accident.
(1) Interlock circuits for conflicting operations such as forward/backward rotation or for machine
damage prevention such as upper/lower limits shall be configured outside of the product.
(2) If this product detects a communication abnormality, it will stop operation and set all outputs
to OFF/HOLD. In addition, if an input/output control section has an abnormality which cannot
be detected by the microcomputer within this product, all outputs may be turned on. In suchcase, an external fail-safe circuit or mechanism shall be installed for this product so that themachine operates at the safe side.
(3) Outputs may be set to on or off at all times depending on a breakdown of an output circuit
transistor etc. For output signals which may cause serious accidents, an external monitoring
circuit shall be installed.
● A fuse or other safety circuits shall be installed externally since smoke/fires may occur if a load
current which is higher than the rated current or an over current by a load short circuit flows
continuously for a long time.
● A circuit of the external power supply for input/output circuits shall be configured so that thepower supply is turned on after the power supply for this product is turned on. If the external
power supply is turned on first, erroneous output or malfunctions may cause an accident.

CAUTION● Control wires and power supply cables shall not be bundled with the main circuit and powerwires or be laid close to them. Separate them by 100 mm (3.9 in) or more. Noise may cause
malfunction.
● An output circuit with a margin in the rated current shall be selected, because large currents (tentimes greater than normal ones) may flow when the output is set to ON from OFF on control oflamp load or others at the output circuit.

[INSTALLATION PRECAUTIONS]CAUTION● This product shall be used with the environmental specifications described in this user's manual.
If it used in an environment outside of the environmental specification range, electric shocks,
fires, malfunctions, product damage, or degradation may occur.
● Do not directly touch the conductive section of this product. Malfunctions and breakdowns may
occur.
● When installing the wireless unit, avoid the area around the processing machine. Noise andother factors may cause communication problems.
● The combination of antenna and wireless unit has been certified to comply with technicalstandards, so please do not combine it with an antenna of a different compatible model or anantenna made by another company.

[STARTING/MAINTENANCE PRECAUTIONS]WARNING● Do not touch terminals while the product is energized. An electric shock may occur.
● Be sure to block power supply externally for all phases before cleaning.
If all phases are not blocked, an electric shock may occur.
Tightening screws too much may damage the product causing it to fall.
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CAUTION● Do not disassemble or modify the product. Breakdowns, malfunctions, injuries, or fires may
occur. Also, that is prohibited by the Radio Law.

[DISPOSAL PRECAUTIONS]CAUTION● When this product is disposed of, it shall be handled as industrial waste.

警語
經型式認證合格之低功率射頻電機，非經許可，公司、商號或使用者均不得擅自變更頻率、
加大功率或變更原設計之特性及功能。
低功率射頻電機之使用不得影響飛航安全及干擾合法通信；經發現有干擾現象時，應立即停用，並改善至無干擾時方得繼續使用。
前項合法通信，指依電信法規定作業之無線電通信。低功率射頻電機須忍受合法通信或工業、科學及醫療用電波輻射性電機設備之干擾。

2. USER’S MANUALNo.

Manual nameManual No.

1

2.4 GHz Band Wireless Unit (SWL31-ETMC, SWL31-R4ML)
User's Manual (Detailed Version)

X903150801

22.4 GHz Band Wireless Unit Setting Utility(SWL31-UT1)
User's Manual

X903130102

OVERSEAS SUPPORT GROUP （JAPAN）
Mail ： osb.webmaster@melsc.jp

3. CHECKING PACKAGE
Open the package and check the package to see if the set you have ordered is included.
Set model name(1) SWL31-ETMC(2) SWL31-R4ML
No.

Item name

1
2
3
4
5

2.4 GHz Band Radio Unit SWL31-ETMC (Master Station)
2.4 GHz Band Radio Unit SWL31-R4ML (Slave Station)
DIN Rail Mounting Attachment
DRT-1
Attachment Fixing Screws (Pan Tapping Screws M3 x 8)
User's Manual (Hardware Version)※Antennas must be purchased separately, refer to 4. Antenna (sold separately)

4/16

Set Contents
(1)
(2)
1
―
―
1
1
1
1
1
1
1

4. Antenna (sold separately)No.
1
2

Item name
Pencil Type Antenna
Flange Head Type Antenna (Cord 2 m (78.7 in)) ※SWL31-ANP
SWL31-ANT※If you buy Flange Head Type Antenna, you will get Flange Head Type Antenna Fixture Set

5. WIRELESS UNIT INSTALLATION ENVIRONMENT● Installation Environment
Install the Wireless Unit avoiding the following environments.
• A place with direct sun light• A place with extremely high humidity• A place with corrosive or inflammable gases• A place with intense electric field or ferromagnetic field occurrence● Request on Installing Wireless Unit
The Wireless Unit transmits/receives data using radio waves. For using it with stablecommunication status, install it paying attention on the following.
• Install the antennas of the units which communicate parallel to each other as much as
possible.
• Place metallic plates and concrete walls away from the antenna as far as possible (0.3 m(11.8 in) at least).
• Install the antenna at a place 1.5 m (59.1 in) or higher from the floor to prevent impact frommoving objects (including human bodies).
• When communications are checked with a temporal installation, the unit shall be installed ona control board or others which the unit is actually to be installed because communications
are affected by the environment near the fixing part such as metal and concrete. (If the
Wireless Unit is installed in a metallic control board, install the flange head antenna outsideof the board.)• The Wireless Unit and antenna are indoor types.
If they are used outdoors, place them avoiding water (rain, fog, snow, etc.) and direct sun light ina nonmetallic container such as a plastic case for outdoors.
Impact of water on the communication distance is assumed for electric wave characteristics.
In addition, if the plastic case has a metallic plate embedded, it shall not be used because it will
be an obstruction and significantly affect the communication distance.

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6. Certification standard
Available countries
Japan
China
TaiwanThailand
VietnamWireless certification standard
ARIB STD-33/T66
― *
NCC
NBTC
MIC
FCC part 15B
FCC Part 15C
FCC IDICES 003
RSS 210IC ID
AS/NZS 4268
AS/NZS 4268

USA

CanadaAustralia
new Zealand* Not subject to CCC certification, SRRC certification not required

7. INSTALLATION & WIRING
7-1. Installation
The unit can be installed to the DIN rails (35 mm (1.38 in) with the DIN rail mounting attachment or
installed with screws. (SWL31-ETMC and SWL31-R4ML can be installed with the same installation
method.)(1) Installing to the DIN rail
DIN
Mounting
Attachment
Hole
DIN Rail
rail Mounting
AttachmentHole
4-2.4×6

DIN rail Mounting
DIN Rail Mounting
Attachment
Attachment

55

Antenna side20

Pay attention to themounting direction.

Rear ofof UnitRear
Unit

1) Install the DIN rail mounting attachment to the rear of the Wireless Unit with the M3 tapping screws(*1). (Screw tightening torque: 30 to 42 Ncm)
2) Hook the claw (upper side) of the DIN rail mounting attachment to the DIN rail.
3) Push the claw (lower side) until a clicking sound is heard.
*1: Use only the tapping screws packed together. If not, racing or damage may occur.

(2) Screwing
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Mounting Hole
Processing Dimension

2-3.1(Main Body
Mounting Hole)

81±0.2

Fix the unit with two screws.

57±0.27-2. Wiring
For the terminal layout and conforming electric wire size, refer to "9-8. Terminal Block Specification."* To prevent induction noise, lay the power line and the signal line away from each other as far as
possible. (It is recommended that they are away from each other 100 mm (3.94 in) or more.)● Wiring Master Station(1) Connect the unit power supply.
(2) Connect the FG terminal to the ground.
● Wiring Slave Station(1) Connect the unit power supply.
(2) Connect the Expansion link.
(3) Connect the I/O signal line.
(4) Connect the error signal line.
● Wiring Expansion Unit (SWLEX-X16/SWLEX-XY16/SWLEX-AD4)(1) Connect the unit power supply.
(2) Connect the signal line.
(3) Connect the link cable to the slave station and Expansion unit.
* Expansion unit link maximum communication distance: 1000 m (3280 ft)* For connection locations, refer to the figure below.

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[Wiring Expansion Unit Link]
Expansion Unit 1

Expansion Unit 2
*2

TERM

TERM

DG

DG (EXG)

DG (EXG)DB

DB (EXO)

DB (EXO)DADA (EXI)DA (EXI)

Slave *1
Station

RS485 cable with ashield recommended*1: A terminal resistor is implemented within the slave
station.

RS485 cable with ashield recommended*2: Connect TERM to DB (EXO) of the expansion unit connectedto the terminal to use a terminal resistor within the unit.

[Screw-less Terminal Block Connection Method]• Peel 8 mm (0.31 in) of the electric wire end as in the figure on the right.
• Insert the electric wire pressing the stopper with a screwdriver.
• Leave the screwdriver from the stopper to fix the electric wire.

8mm

8. INSTALLATION PROCEDURE & SET THE PARAMETERS
For details, refer to …
"2.4 GHz Band Wireless Unit (SWL31-ETMC, SWL31-R4ML) User's Manual (Detailed Version)""2.4 GHz Band Wireless Unit Setting Utility(SWL31-UT1) User's Manual"
OVERSEAS SUPPORT GROUP （JAPAN）
Mail ： osb.webmaster@melsc.jp

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9. NAME/FUNCTION OF EACH SECTION● SWL31-ETMC (Master Station)

Status Monitor
Antenna
Radio Monitor

Ethernet Monitor
Operation Buttons

USB Connector
SWL31-ETMC

Terminal Block
Stopper

Ethernet Connector

Category
Antenna

Name

PW
Radio Monitor
TX
RX

Status Monitor(Seven Segment)

Ethernet
Monitor

100M
SD
RD
MODE/BACK

Operation
Buttons▼ (Down key)
▲ (Up key)
SET

Terminal Block
Stopper
Ethernet Connector
USB Connector

Explanation
A pencil type or flange head type (antenna)
Lighting-on: Power on, normal communications
Blinking:
Power on, error occurred, parameter setting
mode activatedLighting-off: Power off
Lighting-on while radio data are transmitted
Lighting-on while radio data are received
Various displays with operation modes• In Normal Mode
Normal communication: The channel number is displayed.
Error occurred: The error number is displayed.
• In Parameter Setting Mode: The parameter number isdisplayed.
• In Radio Wave Intensity Mode: The radio wave intensity
level is displayed.
Lighting-on during 100BASE-TX communications
Lighting-on during data transmission
Lighting-on during data reception
Operation mode switching and hierarchy transfer inParameter Setting Mode
Parameter no./value increase/decrease in Parameter
Setting Mode
Hierarchy transfer in Parameter Setting Mode
Refer to Section 9-8 Terminal Block Specification.
Press the stopper to insert an electric wire and leave it to fix
the wire.
A PLC is connected with an Ethernet cable forcommunications.
A PC is connected to the USB connector for using theSetting Utility (SWL31-UT1).
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● SWL31-R4ML (Slave Station and Relay Station)

Status Monitor
Antenna
Radio Monitor

I/O Monitor
Operation Buttons

USB Connector
SWL31-R4ML

Terminal Block
Stopper
Category
Antenna

Name

PW
Radio Monitor
TX
RX

Status Monitor(Seven Segment)

X0, X1I/O Monitor

Y0, Y1
MODE/BACK

Operation
Buttons
Terminal Block
StopperUSB Connector▼ (Down key)
▲ (Up key)
SET

Explanation
A pencil type or flange head type (antenna)
Lighting-on: Power on, normal communications
Blinking:
Power on, error occurred, parameter setting
mode activatedLighting-off: Power off
Lighting-on while radio data are transmitted
Blinking while radio link is connected
Various displays with operation modes• In Normal Mode
Normal communication: The channel number is displayed.
Error occurred: The error number is displayed.
• In Parameter Setting Mode: The parameter number isdisplayed.
• In Radio Wave Intensity Mode: The radio wave intensity
level is displayed.
Lighting-on when X0 or X1 signal is input to the terminal block
Lighting-on when Y0 or Y1 signal is output from the terminal
block
Operation mode switching and hierarchy transfer inParameter Setting Mode
Parameter no./value increase/decrease in Parameter Setting
Mode
Hierarchy transfer in Parameter Setting Mode
Refer to Section 9-8 Terminal Block Specification.
Press the stopper to insert an electric wire and leave it to fix
the wire.
A PC is connected to the USB connector for using the Setting
Utility (SWL31-UT1).

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10. SPECIFICATIONS
10-1. General Specifications
Item
Target Unit
Operating Ambient
Temperature
Operating Ambient
Humidity
Storage Ambient
Temperature
Storage Ambient
Humidity
Rated operational
Voltage
Current Consumption
Rated PowerSpecifications
SWL31-ETMC (Master Station)
SWL31-R4ML (Slave Station)
0 to +55 degrees C
5 to 95%RH (No condensation)-10 to +65 degrees C
5 to 95%RH (No condensation)
12/24 V DC (10.2 to 26.4 V DC)

60 mA or lower (For 24 V DC)
55 mA or lower (For 24 V DC)
1.5 W
1.4 W
Noise voltage: 500 Vp-p, Noise width: 1 μs
Noise Resistanceby a noise simulator with noise frequency of 45 Hz
Frequency: 10 to 150 Hz
Vibration ResistanceAcceleration: 9.8 m/s2
No. of sweeps: Ten times each in X, Y and Z direction
Acceleration: 147 m/s2
Shock ResistanceNo. of shocks: Three times each in X, Y and Z direction
Operating Atmosphere
No dust or corrosive gas *1
WeightApprox. 130 g (with a pencil type antenna equipped)*1: The special corrosion proof coating cannot be supported since the radio characteristics change.

10-2. Radio Communication
Item
Target Unit
Communication Method
Communication Topology
Maximum No. of Relay
Units
Operation Usage
Frequency Band
No. of Frequency
Channels
Antenna Power
Communication Speed

Specifications
SWL31-ETMC (Master Station) and SWL31-R4ML (Slave Station)
Polling systemMesh
3 units
ISM 2.4 GHz frequency band
2.405 GHz to 2.475 GHz (5.0 MHz interval)
15 ch

6.3 mW or lower
250 kbps
Indoors: Approx. 60 m(197 ft)(prospect),Transmission Distance *1
Outdoors: Approx. 300 m(984 ft) (prospect)• For one slave station: Approx. 50 ms + 150 ms
Response Time *1• For n units of slave station: Approx. 50 ms x n units + 150 ms*1: The values are ones obtained when no relay unit exists. Also, they depend on surrounding
environments such as obstacles.

11/16

10-3. Ethernet Communication
Item
Target Unit
Interface
Maximum Bit Number
Maximum Word Number
Max No. of Slave Stations
Connected

Specifications
SWL31-ETMC (Master Station)
Ethernet (100BASE-TX, TCP/IP, and others, Connector: RJ-45)
MC Protocol (3E frame client)
MC Protocol (1E frame client)
Input 2048 points, Output 2048 points (system area included)
Input 256 points, Output 256 points
40 units (depends on the no. of Expansion units
connected)

10-4. Slave Station Interface Specifications
Item

Specifications
Target Unit
SWL31-R4ML (Slave Station)
Number of Bits Occupied
Input: 16 bits/per unit
Output: 16 bits/per unit
(Only Slave Station)
Number of Words Occupied
Input: Max four words/per unit *1
Output: Max four words/per unit *1(Only Slave Station)
Max No. of Bits Occupied
Input: 144 points (system area included)
Output: 144 points (system area included)(Expansion Units Included)
Max No. of Words Occupied
Input: 36 points
Output: 36 points(Expansion Units Included)
Input 2 points/Output 2 points + Error output 1 point
I/O Interface(Input 2 points can be switched to the pulse count 2ch/1ch.)
Maximum two channels available
0 to 99999999
Pulse Count Function
8 digits(Memory retention available at power failure)( A ring counter)*1: Words are occupied when the pulse count function is used. (Two word occupation per channel)

12/16

10-5. Input Specifications
Item

Specifications

Target Unit

SWL31-R4ML (Slave Station)

Input TypeDC input (a plus common/minus common shared type)

Input Points
Insulation Method

2 points
Photocoupler insulation

Rated Input Voltage
Rated Input Current

12/24 V DC (+10/-15%, Ripple rate 5% or less)Approx. 3 mA for 12 V DC, Approx. 7 mA for 24 V DC

ON Voltage/ON Current
OFF Voltage/OFF Current

8 V or higher/2 mA or higher
4 V or lower/1 mA or lower

Input ResistanceApprox. 3.3 kΩ
OFF→ON

Response Time
ON→OFF
Common TypeOperation Display

200 ms or less (One master and One slave station
communication: no relay)
200 ms or less (One master and One slave station
communication: no relay)
2 points per common
ON display (LED)

External Connection Diagram

10-6. Pulse Count Specifications
Item
Number of Channels
Input Voltage Specifications
Minimum Input Pulse Width

Specifications
2ch/1ch * Selectable with the parameter
12/24 V DC
30 Hz (ON: 16.7 ms, OFF: 16.7 ms)* When the machine contact output is used, the chattering time shallbe considered.
Counter Type
Ring counter type
Number of Digits
1 to 8 digits
Default Setting
The count value can be set with other than 0 with the operation
buttons of the slave station.
Reset
External Reset Turning on the input terminal (X1) of the slave station resets the count.
Method* When 2ch is used, the external reset is unavailable.
Commanding internal reset from the sequence program to the master
Internal Resetstation resets the count.
Note: If the pulse count is used the master station parameter for the word data of the PLC shall be set to
Hold not to be cleared (to zero) at radio error.
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10-7. Output Specifications
Item
Target Unit
Output Type
Output Points

Specifications
SWL31-R4ML (Slave Station)
Transistor output (sync type)
3 points (error output signal 1 point included)

Insulation Method

Photocoupler insulation

Rated Load Voltage

12/24 V DC (+10/-15%)

Maximum Load Current

0.1 A/1 point, 0.3 A/1 common(error output signal 1 point included)

OFF→ON

Response Time
ON→OFF

Surge Killer
Fuse
External Power
SupplyVoltage
Current

Common Type

200 ms or less (One master and One slave station
communication: no relay)
200 ms or less (One master and One slave station
communication: no relay)
Zener diodeNone
12/24 V DC (+10/-15%) (Ripple rate 5% or less)
10 mA (for 24 V DC)
3 points per common (error output signal 1 point included)Internal
circuit

External Connection Diagram

Y0

L

R
Y1
ERR

L
L

+
COM12/24 V DC

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10-8. Terminal Block Specifications● Master Station (SWL31-ETMC)[Terminal Block Diagram][Terminal Layout]
Item
Unit Power Supply +Unit Power Supply FG Terminal

123

Terminal no.
1
2
3

Silk notation+
FG

Specifications
Unit power supply (12 to 24 V DC)
FG connection terminal[Terminal Specifications]
Item
Conforming Electric Wire
Size
Standard Peeling Length
Recommended
Conforming Tool

Specifications
Single wire: φ0.8 mm(0.03 in) (AWG20),
twisted wire 0.5 mm2 (AWG20),
strand diameter φ0.18 mm(0.007 in) or more
8 mm(0.31 in)Flathead screwdriver
Shaft diameter φ3 mm(0.11 in),cutting edge width 2.6 mm(0.1 in)● Slave Station (SWL31-R4ML)[Terminal Block Diagram]

1 2 3 4 5 6 7 8 9 10 11 12 13[Terminal Layout]
Item
Unit Power Supply +Unit Power Supply Expansion Unit Link DG
Expansion Unit Link DB
Expansion Unit Link DA
Input Signal X0
Input Signal X1
Input Signal Common COM
Output Signal Y0
Output Signal Y1
Error Output Signal
Gate Power Supply +Output Signal Common COM -Terminal no.
1
2
3
4
5
6
7
8
9
10
11
12
13

Silk notation
+
DG
DB
DA
X0
X1
COM
Y0
Y1
ERR
+
COM-

Specifications
Unit power supply (12 to 24 V DC)
Expansion link communication(RS485)
Refer to 9-5. Input Specifications.

Refer to 9-7. Output Specifications.

[Terminal Specifications]
Item
Conforming Electric Wire
Size
Standard Peeling Length
Recommended
Conforming Tool

Specifications
Single wire: φ0.8 mm(0.03 in) (AWG20),
twisted wire 0.5 mm2 (AWG20),
strand diameter φ0.18 mm(0.007 in) or more
8 mm(0.31 in)Flathead screwdriver
Shaft diameter φ3 mm(0.11 in),cutting edge width 2.6 mm(0.1 in)
15/16

10-9. Appearance Specifications● SWL31-ETMC● SWL31-R4ML(Pencil Type Antenna implemented)(Pencil Type Antenna implemented)

81
89

85

SWL31-R4ML

52

52

SWL31-ETMC

4

81
89

85

4

57

57
35

65

35

35

29

65

Unit [mm]120±2●SWL31-ANT (Flange Head Type Antenna)

φ6.5

21

RG174ケーブル
SMA-P

φ27

2000 +50-0

Ethernet is a trademark of FUJIFILM Business Innovation Corp.
MC Protocol is an abbreviation of MELSEC Communication Protocol.
MELSEC is a trademark of Mitsubishi Electric Corporation.

C&C CENTER OVERSEAS SUPPORT GROUP（JAPAN）
Mail ： osb.webmaster@melsc.jp･The contents of this manual are subject to change without prior notice.
･Unauthorized reproduction prohibited

X903150601F

Issue Date: March, 2024
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