The Ebyte NB144ES is an industrial-grade 4-channel serial device server and Modbus TCP/RTU gateway supporting RS232, RS422, and RS485 to RJ45 Ethernet transparent transmission. It features IEEE 802.3af POE power receiving, DC 8-28V wide-range voltage input, automatic Modbus polling, and multi-protocol networking (TCP, UDP, MQTT, HTTP) engineered for harsh industrial automation environments.
| Parameter | Technical Specification |
|---|---|
| Model / SKU | EBYTE NB144ES |
| Serial Interfaces | 4 Channels (Interface 1: Isolated RS485; Interface 2: Standard DB9 Female RS232; Interface 3: Isolated RS422) |
| Network Interface | 1x RJ45 Port (10M Ethernet, Supports Standard POE Receiving Power) |
| Serial Baud Rate | 2400 to 115200 bps (Default: 115200 bps) |
| Operating Modes | TCP Server (Default), TCP Client, UDP Server, UDP Client, HTTP Client, MQTT Client |
| Modbus Gateway Function | Modbus TCP to Modbus RTU Conversion, Automatic Polling |
| Network Protocols | TCP/IP, UDP, MQTT, HTTP, IPv4, ICMP, ARP, DHCP, DNS |
| Power Supply Options | DC 8V to 28V (5.08mm Phoenix Crimp Terminal or 5.5x2.0mm DC Female Jack) / POE Power Supply |
| Buffer & Packaging | 512 Bytes Serial Cache, 512 Bytes Serial Packaging Mechanism |
| Operating Temp & Humidity | -40 to +85 deg C, 5% to 95% RH (Non-condensing) |
| Dimensions & Weight | 198 x 109 x 26.5 mm (LxWxH), 530g +/- 5g |
|
Project |
Interface |
illustrate |
|
power supply |
Crimp terminal |
DC 8～28 Power supply, used when not available; |
|
D C female |
D C female head: straight plug-in round hole, outer diameter |
|
|
Network port |
RJ45 |
10M |
|
serial port |
Channel 1 to |
Interface 1 ( RS485 , 3.81mm Phoenix terminal, support isolation); |
|
Operating mode |
TCP Server (default), TCP Client, UDP Server, UDP Client, HTTP Client , MQTT Client |
|
|
Network protocol |
TCP/IP, UDP, MQTT , HTTP , IPv4, I CMP , APR , D HCP , D NS |
|
|
IP acquisition method |
DHCP, static IP (default) |
|
|
DNS |
Support, address can be configure |
|
|
configuration method |
Parameter configuration host computer , AT command |
|
|
IP address |
192.168.3.7 (customizable) |
|
|
local por |
Channel 1~ 4 : 8 001-800 4 (can be customized) |
|
|
subnet mask |
255.255.255.0 (customizable) |
|
|
gateway |
192.168.3.1 (customizable) |
|
|
Serial cache |
512 Byte |
|
|
Serial packaging |
512 Byte |
|
|
Serial baud rate |
2400 ~ 115200 bps (default 115200) |
|
|
data bit |
8 |
|
|
stop bit |
1 (default),2 |
|
|
Check Digit |
None (default), Odd, Even |
|
|
installation method |
positioning hole |
|
|
Product Size |
198 x 108x26.5mm （LxWxH） |
|
|
product weight |
530g ± 5g |
|
|
Working temperature |
-40 ～ +85°C, 5% ～ 95%RH (no condensation) |
|
|
storage temperature |
-40 ～ +105°C, 5% ～ 95%RH (no condensation) |
|
Practical Application Scenarios
1. Multi-Device Industrial Substation & Power Monitoring System
In smart grid control cabinets, field meters and power analyzers communicate using legacy RS485 or RS232 Modbus RTU protocols. The Ebyte NB144ES acts as a central Modbus TCP gateway, using its 4 independent serial ports to aggregate telemetry from multiple power meters simultaneously. Through its internal protocol stack and hardware-isolated RS485 terminals, it converts field serial data into Ethernet frames, routing real-time voltage, current, and energy metrics over an industrial local area network to centralized SCADA systems.
2. Factory Automation Hybrid Network Integration with Ebyte LoRa DTU Gateways
In large manufacturing facilities requiring both wired Ethernet and wireless sub-GHz connectivity, the NB144ES serves as the main wired communications node. Legacy PLC systems connected to the NB144ES via RS422 or RS232 interfaces send control commands over TCP/IP. When paired with Ebyte wireless LoRa DTUs or wireless I/O modules operating across distant production lines, the NB144ES provides a stable wired Ethernet bridge to backhaul telemetry from remote wireless nodes back to the central MES server.
3. Smart Building Management and Environmental Sensing Network
Modern HVAC, lighting controllers, and environmental sensor clusters often rely on diverse serial interfaces across different floors. The NB144ES bridges these isolated serial networks to a single Ethernet backbone using Power over Ethernet (POE), eliminating the need for dedicated power cables at each installation point. By enabling MQTT Client mode, the unit directly publishes serial sensor data to cloud-based IoT management platforms or local building management automation controllers via lightweight TCP/UDP sockets.
FAQ Section
1. Does the Ebyte NB144ES support simultaneous communication across all 4 serial ports?
Yes. The NB144ES features 4 independent serial communication channels operating concurrently. Each channel maps to individual local communication ports (by default assigned to ports 8001 through 8004), allowing host computers, PLCs, or SCADA software to establish separate TCP or UDP connections to each serial port interface without data collision or crosstalk.
2. How does the NB144ES handle protocol conversion between Modbus RTU and Modbus TCP?
The NB144ES includes built-in Modbus gateway functionality with support for Modbus TCP to RTU bi-directional protocol conversion. Additionally, it supports hardware-level automatic polling. The gateway autonomously queries downstream Modbus RTU field slave devices according to pre-configured polling tables and stores the data locally, enabling upstream Modbus TCP clients to read cached register values instantly with minimal network latency.
