Moxa Technologies NPort W2150A-W4 Series User manual

NPort W2150A-W4/W2250A-W4 Series
User Manual
Version 1.0, January 2023
www.moxa.com/products
© 2023 Moxa Inc. All rights reserved.

NPort W2150A-W4/W2250A-W4 Series User Manual
The software described in this manual is furnished under a license agreement and may be used only in accordance
with the terms of that agreement.
Copyright Notice
© 2023 Moxa Inc. All rights reserved.
Trademarks
The MOXA logo is a registered trademark of Moxa Inc.
All other trademarks or registered marks in this manual belong to their respective manufacturers.
Disclaimer
•Information in this document is subject to change without notice and does not represent a commitment
on the part of Moxa.
•Moxa provides this document as is, without warranty of any kind, either expressed or implied, including,
but not limited to, its particular purpose. Moxa reserves the right to make improvements and/or
changes to this manual, or to the products and/or the programs described in this manual, at any time.
•Information provided in this manual is intended to be accurate and reliable. However, Moxa assumes no
responsibility for its use, or for any infringements on the rights of third parties that may result from its
use.
•This product might include unintentional technical or typographical errors. Changes are periodically
made to the information herein to correct such errors, and these changes are incorporated into new
editions of the publication.
Technical Support Contact Information
www.moxa.com/support

Table of Contents
1. Introduction .........................................................................................................................................5
Overview .............................................................................................................................................. 5
Package Checklist .................................................................................................................................. 5
Product Features ................................................................................................................................... 6
Serial Port Pin Assignments..................................................................................................................... 6
2. Getting Started .....................................................................................................................................7
Overview .............................................................................................................................................. 7
Panel Layout .........................................................................................................................................7
LED Indicators.......................................................................................................................................8
Top Panel LED Indicators.................................................................................................................8
End Panel LED Indicators.................................................................................................................8
Pull High/Low Resistors for RS-422/485.................................................................................................... 9
Placement Options ............................................................................................................................... 10
Connecting the Hardware...................................................................................................................... 10
Connecting to the Network ............................................................................................................ 11
Connecting the Power ................................................................................................................... 11
Connecting to a Serial Device ........................................................................................................ 11
3. Initial IP Configuration.......................................................................................................................12
Overview ............................................................................................................................................ 12
Factory Default IP Settings ................................................................................................................... 12
Using the Telnet Console to an Assign IP Address .................................................................................... 12
Using the Serial Console to an Assign IP Address ..................................................................................... 15
4. Introduction to Operation Modes ........................................................................................................17
Overview ............................................................................................................................................ 17
Real COM Mode ................................................................................................................................... 17
RFC2217 Mode .................................................................................................................................... 18
TCP Server Mode ................................................................................................................................. 18
TCP Client Mode .................................................................................................................................. 18
UDP Mode........................................................................................................................................... 19
Pair Connection Modes ......................................................................................................................... 19
Ethernet Modem Mode.......................................................................................................................... 19
Reverse Terminal Mode ........................................................................................................................ 20
5. Installing and Configuring the Software .............................................................................................21
Overview ............................................................................................................................................ 21
Device Search Utility (DSU) .................................................................................................................. 21
Installing the DSU ........................................................................................................................ 21
Finding NPort Device Servers on a Network ..................................................................................... 23
Modifying NPort IP Addresses......................................................................................................... 24
Upgrading NPort Firmware............................................................................................................. 25
NPort Windows Driver Manager ............................................................................................................. 27
Installing NPort Windows Driver Manager ........................................................................................ 27
Adding Mapped Serial Ports ........................................................................................................... 30
Configuring Mapped Serial Ports..................................................................................................... 32
Command-Line Installation/Removal............................................................................................... 37
Linux Real TTY Drivers ......................................................................................................................... 39
Basic Steps.................................................................................................................................. 39
Installing Linux Real TTY Driver Files .............................................................................................. 39
Enter the new IP address and netmask. If multiple units were selected, you mayMapping TTY Ports ....... 39
Removing Mapped TTY Ports.......................................................................................................... 40
Removing Linux Driver Files........................................................................................................... 40
UNIX Fixed TTY Drivers ........................................................................................................................ 40
Installing the UNIX Driver.............................................................................................................. 41
Configuring the UNIX Driver .......................................................................................................... 41
6. Web Console: Basic Settings...............................................................................................................43
Overview ............................................................................................................................................ 43
Basic Settings ..................................................................................................................................... 44
7. Web Console: Network Settings..........................................................................................................46
Overview ............................................................................................................................................ 46

Network Settings ................................................................................................................................. 46
General Settings .......................................................................................................................... 46
Ethernet/Bridge Settings ............................................................................................................... 47
WLAN Settings ............................................................................................................................. 49
Advanced Settings........................................................................................................................ 61
8. Web Console: Serial Port Settings.......................................................................................................62
Overview ............................................................................................................................................ 62
Serial Port Settings....................................................................................................................... 62
Communication Parameters ........................................................................................................... 81
Data Buffering/Log ....................................................................................................................... 82
9. Web Console: System Management ....................................................................................................84
Overview ............................................................................................................................................ 84
System Management............................................................................................................................ 84
Misc. Network Settings.................................................................................................................. 84
Auto Warning Settings .................................................................................................................. 88
Maintenance ................................................................................................................................ 91
Certificate ................................................................................................................................... 95
10. Web Console: System Monitoring .......................................................................................................99
Overview ............................................................................................................................................ 99
System Monitoring............................................................................................................................... 99
Serial Status................................................................................................................................ 99
System Status ........................................................................................................................... 101
11. Web Console: Restart .......................................................................................................................105
Overview .......................................................................................................................................... 105
Restart............................................................................................................................................. 105
Restart System .......................................................................................................................... 105
Restart Ports.............................................................................................................................. 105
12. Android API Instructions ..................................................................................................................106
Overview .......................................................................................................................................... 106
How to Start MxNPortAPI ............................................................................................................ 107
MxNPortAPI Function Groups............................................................................................................... 108
Example Program .............................................................................................................................. 108
A. SNMP Agents with MIB II & RS-232-Like Groups..............................................................................109
RFC1213 MIB-II Supported SNMP Variables .......................................................................................... 109
System MIB............................................................................................................................... 109
Interfaces MIB ........................................................................................................................... 109
IP MIB ...................................................................................................................................... 109
ICMP MIB .................................................................................................................................. 110
UDP MIB ................................................................................................................................... 110
Address Translation .................................................................................................................... 110
TCP MIB .................................................................................................................................... 110
SNMP MIB ................................................................................................................................. 110
RFC1317: RS-232 MIB Objects ............................................................................................................ 111
Generic RS-232-like Group .......................................................................................................... 111
RS-232-like General Port Table .................................................................................................... 111
RS-232-like Asynchronous Port Group........................................................................................... 111
The Input Signal Table ................................................................................................................ 111
The Output Signal Table .............................................................................................................. 111
B. Well-known Port Numbers................................................................................................................112
C. Ethernet Modem Commands .............................................................................................................114
Dial-in Operation ............................................................................................................................... 114
Dial-out ............................................................................................................................................ 114
Disconnection Request from Local Site ................................................................................................. 114
Disconnection Request from Remote Site.............................................................................................. 114
AT Commands................................................................................................................................... 115
S Registers ....................................................................................................................................... 116

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1. Introduction
Overview
In this chapter, we introduce the basic features and specifications of the NPort W2150A-W4/W2250A-W4
Series and NPort W2150A-W4/W2250A-W4 Series-T, referred to collectively as the NPort W2150A-
W4/W2250A-W4 Series.
The NPort W2150A-W4/W2250A-W4 Series of wireless device servers are used to connect RS-232/422/485
serial devices or Ethernet devices, including PLCs, meters, and sensors, to a wireless LAN. Your
communications software will access the serial devices or Ethernet devices from anywhere over a local LAN,
WLAN, or the Internet. Moreover, the WLAN environment offers an excellent solution for applications in
which the serial devices and Ethernet devices are moved frequently from place to place.
The NPort W2150A-W4/W2250A-W4 Series supports automatic IP configuration protocol (DHCP) and
manual configuration using a standard web browser. Both IP configuration methods ensure quick and
effective installation. In addition, a utility called “NPort Windows Driver Manager” makes port mapping easy.
The external antenna can be adjusted for maximum signal strength. You can also choose to use your own
antenna for additional flexibility and scalability. A signal strength indicator on the front panel makes it easier
for you to troubleshoot any connection problems.
The NPort W2150A-W4/W2250A-W4 Series offers different operation modes to ensure compatibility with
standard network APIs, including TCP Server Mode, TCP Client Mode, and UDP Mode. Real COM/TTY drivers
are provided to allow legacy serial-based software to communicate over an IP network instantly. This
preserves your software investment while providing all the advantages of networking your serial devices.
For easier management, the NPort W2150A-W4/W2250A-W4 Series includes features such as password
authentication, IP filtering, 64-bit and 128-bit WEP encryption, and SNMP support.
Package Checklist
Standard Accessories
•1 NPort W2150A-W4 or NPort W2250A-W4 wireless device server
•1 antenna 2.4/5 GHz: ANT-WDB-ASM-03 BK
•100 to 240 VAC power adapter (excluding T models)*
•1 Ethernet cable: CBL-RJ458P-100
•Quick installation guide (printed)
•Warranty card
NOTE
The package includes one power adapter suitable for your region.
NOTE
The operating temperature of the power adapter (included with the NPort W2150A-W4/W2250A-W4) is
from 0 to 40°C (32 to 104°F). If your application is not in this range, please use a power adapter supplied
according to the requirements below:
•The external power source must comply with UL listed, IEC 60950-1, or IEC/EN 62368-1
•Output complies to SELV/ES1, PS2/LPS; output rating 12 to 48 VDC, 0.455 A minimum
•A minimum ambient temperature of 55˚C or 75˚C. (55˚C for the NPort W2150A-W4 and NPort
W2250A-W4; 75˚C for the NPort W2150A-W4-T and NPort W2250A-W4-T)

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Optional Accessories
•DK35A: DIN-rail mounting kit (35 mm)
•Power-jack-to-terminal-block 12 cable (P/N: 9199000000900)
NOTE
Please notify your sales representative if any of the above items is missing or damaged.
Product Features
•Links serial and Ethernet devices to an IEEE 802.11a/b/g/n network
•Web-based configuration using built-in Ethernet or WLAN
•Secure boot for Moxa only authorized firmware allowed to run
•Remote configuration with HTTPS, SSH
•Secure data access with WEP, WPA, WPA2
•Fast roaming for quick automatic switching between access points
•Enhanced surge protection for serial, LAN, and power
•Offline port buffering and serial data log
•Dual power inputs (1 screw-type power jack, 1 terminal block)
Serial Port Pin Assignments
Pin
RS-232
RS-422/ RS-485 (4W)
RS-485 (2W)
1
DCD
TxD-(A)
–
2
RXD
TxD+(B)
–
3
TXD
RxD+(B)
Data+(B)
4
DTR
RxD-(A)
Data-(A)
5
GND
GND
GND
6
DSR
–
–
7
RTS
–
–
8
CTS
–
–
9
–
–
–

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2. Getting Started
Overview
This chapter presents the hardware features of the NPort W2150-W4/W2250A-W4 Series and explains how
to connect the hardware.
Panel Layout
NPort W2150A-W4/W2150A-W4-T
NPort W2250A-W4/W2250A-W4-T

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LED Indicators
Top Panel LED Indicators
Name
Color
Function
Ready
Red
Steady on:
Power is on, and the NPort is booting up.
Blinking:
An IP conflict exists, or the DHCP server did not respond
properly.
Green
Steady on:
The NPort is functioning normally.
Blinking:
The unit is responding to Locate function.
Off
Power is off, or a power error condition exists.
WLAN Green
Steady on:
Wireless enabled
Blinking:
The NPort can’t establish WLAN connection with AP
(Infrastructure)
Off
Wireless not enabled.
Port 1
Port 2
Orange
Serial port is receiving data.
Green
Serial port is transmitting data.
Off
No data is flowing to or from the serial port.
Signal Strength
(5 LEDS)
Red
1 Red - the signal strength (RSSI) is worse than -88 dBm
2 Red - the signal strength (RSSI) is between -87 to -79 dBm
Green
3 Green - the signal strength (RSSI) is between -78 to -68 dBm
4 Green - the signal strength (RSSI) is between -67 to -60 dBm
5 Green - the signal strength (RSSI) is between -59 to -45 dBm
End Panel LED Indicators
Name Color Function
Ethernet
Orange 10 Mbps Ethernet connection
Green 100 Mbps Ethernet connection
Off
Ethernet cable is disconnected

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Pull High/Low Resistors for RS-422/485
You may need to set the pull high/low resistors when termination resistors are used for certain RS-422 or
RS-485 environments.
S4 (Port 1)
S5 (Port 2)
DIP 1
Pull high resistor
DIP 2
Pull low resistor
DIP 3
Termination resistor
DIP 4
Reserved
ON
1 KΩ
1 KΩ
120 Ω
–
OFF
*150 KΩ
*150 KΩ
*N/A
–
*Default
S5 is for NPort W2250A-W4 only
ATTENTION
Do not use the 1 KΩ setting while in RS-232 mode. Doing so will degrade the RS-232 signals and reduce
the effective communication distance.

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Placement Options
The NPort can be placed on a desktop or other horizontal surface. You can also install the NPort on a DIN-
rail or on the wall.
Wall Mounting
DIN-Rail Mounting
Connecting the Hardware
ATTENTION
Before connecting the hardware, follow these important wiring safety precautions:
Disconnect power source
Do not install or wire this unit or any attached devices with the power connected. Disconnect the power
before installation by removing the power cord before installing and/or wiring your unit.
Follow maximum current ratings
Calculate the maximum possible current in each power wire and common wire. Observe all electrical codes
dictating the maximum current allowable for each wire size.
If the current goes above the maximum ratings, the wiring could overheat, causing serious damage to
your equipment.
Use caution - unit may get hot
The unit will generate heat during operation, and the casing may be too hot to touch. Take care when
handling the unit. Be sure to leave adequate space for ventilation.
The following guidelines will help ensure trouble-free signal communication with the NPort.
•Use separate paths to route wiring for power and devices to avoid interference. Do not run signal or
communication wiring and power wiring in the same wire conduit. The rule of thumb is that wiring that
shares similar electrical characteristics can be bundled together.
•If power wiring and device wiring paths must cross, make sure the wires are perpendicular at the
intersection point.
•Keep input wiring and output wiring separate.
•Label all wiring to each device in the system for easier testing and troubleshooting

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Connecting to the Network
Use the supplied Ethernet cable to connect the NPort to your Ethernet network. If the cable is properly
connected, the NPort will indicate a valid connection to the Ethernet as follows:
•A green Ethernet LED indicates a valid connection to a 100 Mbps Ethernet network.
•An orange Ethernet LED indicates a valid connection to a 10 Mbps Ethernet network.
•A flashing Ethernet LED indicates that Ethernet packets are being transmitted or received.
Connecting the Power
Connect the VDC power line (12 to 48 V) to the NPort’s power jack or terminal block (recommended for only
one connection at a time). If power is properly connected, the “Ready” LED will initially glow red. When the
system is ready, the “Ready” LED will turn green.
Connecting to a Serial Device
Use a serial cable to connect your serial device to a serial port on the NPort.

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3. Initial IP Configuration
Overview
This chapter presents several ways to assign the NPort’s IP address for the first time. Please refer to
Chapter 2 for instructions on connecting to the network.
The web console is the recommended method for configuring the NPort. Please refer to Chapter 5 and 6 for
details on using the web console for configuration.
ATTENTION
The LAN and WLAN interfaces cannot be used at the same time if you don't enable the Ethernet Bridge
mode (please refer to Chapter 7 for more details). If the Ethernet link is active, then WLAN connections
will be disabled. If the WLAN connection is active, then the Ethernet link will be disabled.
ATTENTION
Make sure that the Ethernet cable is connected before powering up the NPort.
Factory Default IP Settings
Network Interface
IP Configuration
IP Address
Netmask
LAN
Static
192.168.126.254
255.255.255.0
WLAN
Static
192.168.127.254
255.255.255.0
If your NPort is configured to get its IP settings from a DHCP server but cannot get a response, it will use
the factory default IP address and netmask.
ATTENTION
If you forget the IP address of your NPort, you can look it up using the Device Search Utility (DSU). After
the Device Search Utility (DSU) has found all NPorts on the network, each unit will be listed with its IP
address. Please refer to Chapter 11 for additional information on using the Device Search Utility (DSU).
Using the Telnet Console to an Assign IP
Address
1. Select Command Prompt… from the Windows Start menu.
2. Enter telnet 192.168.126.254 (the NPort’s default IP address) and click [OK].

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3. Enter your login account and password, then press ENTER.
(Default login is admin and password is moxa.)
4. You will login to the Overview page.
5. Press Nor use the cursor keys to select Network and press ENTER.
6. Press Eor use the cursor keys to select Ethernet and press ENTER.

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7. Use the cursor keys to navigate between the different fields. For IP address, Netmask, and Gateway,
enter the desired values directly. For IP configuration, LAN speed, and Ethernet bridge, press
ENTER to open a submenu and select between the available options.
8. Press ESC to return to the menu. When prompted, press Yto save the configuration changes.
•The NPort will reboot with the new IP settings. You can telnet to the new IP to login again.

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Using the Serial Console to an Assign IP
Address
Before using the NPort’s serial console, turn off the power and use a serial cable to connect the NPort
console port to your computer’s serial port. Port 1 on the NPort serves as the console port. Use Port 1
connecting to the console port with a serial-based terminal or terminal emulator program, such as Windows
HyperTerminal. You may also download PComm Lite at www.moxa.com. The terminal type should be set as
ANSI or VT100, and the serial communication parameters should be set as 19200, 8, N, 1 (19200 for baud
rate, 8 for data bits, None for parity, and 1 for stop bits). As soon as the connection is open, you will be
presented with a text menu displaying the NPort W2150A-W4/W2250A-W4 Series general settings. Please
refer to Chapter 4 for a description of the available settings. The following instructions, we recommend
using PComm Terminal Emulator, which can be downloaded free from www.moxa.com, to carry out the
configuration procedure.
1. Connect your PC’s serial port to the NPort’s console port.
2. Open your terminal emulator program, such as Windows HyperTerminal. We recommend using PComm
Terminal Emulator, which can be downloaded for free at www.moxa.com.
3. In your terminal emulator program, configure the communication parameters for the serial port on the
PC. Set the parameters to 19200 for baudrate, 8for data bits, None for parity, and 1for stop bits.

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4. In your terminal emulator program, set the terminal type to ANSI or VT100. If you select Dumb
Terminal as the terminal type, some of the console functions—especially the “Monitor” function—may
not work properly.
5. Hold the grave accent key (`) down and power up the NPort.
The continuous string of grave accent characters triggers the NPort to switch from data mode to console
mode.
6. The serial console will open and will be functionally identical to the Telnet console. Please refer to the
Telnet console section for instructions on how to navigate the console and configure the IP settings.

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4. Introduction to Operation Modes
Overview
This chapter introduces the different serial port operation modes that are available on the NPort W2150A-
W4/W2250A-W4 Series. Each serial port on the NPort is configured independently of the other ports, with its
own serial communication parameters and operation mode. The serial port’s operation mode determines
how it interacts with the network, and different modes are available to encompass a wide variety of
applications and devices.
Real COM and RFC2217 modes allow serial-based software to access the NPort serial port as if it were a
local serial port on a PC. These modes are appropriate when your application relies on Windows or Linux
software that was originally designed for locally attached COM or TTY devices. With these modes, you can
access your devices from the network using your existing COM/TTY-based software, without investing in
additional software.
Three different socket modes are available for user-developed socket programs: TCP Server, TCP Client,
and UDP Server/Client. For TCP applications, the appropriate mode depends on whether the connection
will be hosted or started from the NPort serial port or from the network. The major difference between the
TCP and UDP protocols is that TCP guarantees delivery of data by requiring the recipient to send an
acknowledgement to the sender. UDP does not require this type of verification, making it possible to offer
speedier delivery. UDP also allows multicasting of data to groups of IP addresses and would be suitable for
streaming media or noncritical messaging applications, such as LED message boards.
Pair Connection Slave and Master modes are designed for serial-to-serial communication over Ethernet,
in order to overcome traditional limitations with serial transmission distance.
In Ethernet Modem mode, the NPort acts as an Ethernet modem, providing a network connection to a host
through the serial port.
Real COM Mode
Real COM mode works with NPort drivers that are
installed on a network host. COM drivers are
provided for Windows systems, and TTY drivers are
provided for Linux and UNIX systems. The driver
establishes a transparent connection to the attached
serial device by mapping a local serial port to the
NPort serial port. Real COM mode supports up to
four simultaneous connections, so multiple hosts
can collect data from the attached device at the
same time.
ATTENTION
Real COM drivers are installed and configured through NPort Windows Driver Manager.

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Real COM mode allows you to continue using your serial communications software to access devices that are
now attached to your NPort device server. On the host, the NPort Real COM driver automatically intercepts
data sent to the COM port, packs it into a TCP/IP packet, and redirects it to the network. At the other end of
the connection, the NPort device server accepts the Ethernet frame, unpacks the TCP/IP packet, and sends
the serial data to the appropriate device.
ATTENTION
In Real COM mode, several hosts can have simultaneous access control over the NPort serial port. If
necessary, you can limit access by using the NPort’s Accessible IP settings. Please refer to Chapter 8 for
additional information on Accessible IP settings.
RFC2217 Mode
RFC-2217 mode is similar to Real COM mode, since it relies on a driver to transparently map a virtual COM
port on a host computer to a serial port on the NPort. The RFC2217 standard defines general COM port
control options based on the Telnet protocol and supports one connection at a time. Third party drivers
supporting RFC-2217 are widely available on the Internet and can implement virtual COM mapping.
TCP Server Mode
In TCP Server mode, the NPort serial port is
assigned an
IP:port address that is unique on your
TCP/IP network. It waits for the host computer to
establish a connection to the attached serial device.
This operation mode also supports up to eight
simultaneous connections, so mul
tiple hosts can
collect data from the attached device at the same
time.
Data transmission proceeds as follows:
A host requests a connection to the NPort serial
port.
Once the connection is established, data can be
transmitted in both directions
—from the host to the
device, and from the device to the host.
TCP Client Mode
In TCP Client mode, the NPort actively establishes a
TCP connection to a specific network host when data
is received from the attached serial device. After the
data has been transferred, the NPort can
automatically disconnect from the host computer
through
the Inactivity time settings. Please refer to
Chapter 7 for details on these parameters.
Data transmission proceeds as follows:
The NPort requests a connection from the host.
The connection is established and data can be
transmitted in both directions between the host and
device.

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UDP Mode
UDP is similar to TCP but is faster and more
efficient. Data can be broadcast to or received from
multiple network hosts. However, UDP does not
support verification of data and would not be
suitable for applications wh
ere data integrity is
critical. It is ideal for message display applications.
Pair Connection Modes
Pair Connection Master and Slave modes connect
two NPort device servers over a network for serial
-
to
-serial communication. A device attached to one
NPort
can then communicate transparently to a
device attached to the other NPort, as if
a serial
cable connected the two devices. Both data and
modem control signals are exchanged, except for
DCD signals. This can overcome traditional
limitations with serial co
mmunication distance and
introduce many new possibilities for serial
-based
device control.
Ethernet Modem Mode
Ethernet Modem mode is designed for use with
legacy operating systems, such as MS
-DOS, that do
not support TCP/IP Ethernet. By connecting the
properly configured NPort serial port to the MS
-
DOS
computer’s serial port, it is possible to use legacy
software to transmit data over the Ethernet when
the software was originally designed to transmit
data over a modem.

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Reverse Terminal Mode
Reverse terminal applications are similar to terminal applications, as they use the NPort W2x50A-W4 to
manage the connection between a terminal and a server. The difference is that with reverse terminal
applications; the terminal is connected through the network and the server is connected through the serial
port, rather than the other way around. In practice, a reverse terminal session typically involves a network
administrator telnetting to a device that has a dedicated serial console port used specifically for
configuration.
For example, many routers, switches, UPS units, and other devices (including the NPort W2x50A-W4) have
Console/AUX or COM ports to which a terminal can be physically connected for console management. With
the NPort W2x50A-W4, the device’s console port can be connected to a serial port on the NPort W2x50A-
W4, allowing a network administrator to telnet to the device remotely through the network. Although
modern network equipment allows other options for remote configuration through the network, there are
situations in which it is necessary or desirable to configure a device by serial console (e.g., for security
reasons, when using older-generation equipment, or as a backup configuration method when the network is
down).
NPort W2x50A-W4 reverse terminal modes allow the use of the NPort W2x50A-W4 User Table or a RADIUS
server for identity verification purposes.