ProSoft PLX31-MBTCP-MBS4 Modbus TCP/IP to Modbus Serial 4 Port Gateway

The ProSoft PLX31-MBTCP-MBS4, also cataloged as the PLX31-MBTCP-MBS4 Modbus TCP/IP to Modbus Serial 4 Port Gateway, operates as a dedicated hardware component for bidirectional protocol conversion and signal bridging within Modbus TCP/IP networks and RS-232/RS-422/RS-485 serial field sub-networks. Suffix Breakdown & Model Matrix Model Code Segment Value Hardware/Protocol Definition Platform Series PLX31 Compact Standalone Industrial Standalone Gateway Platform Primary Network MBTCP Modbus TCP/IP Client/Server Ethernet Protocol Interface Secondary Network MBS4 Modbus Serial (RS-232/422/485) Master/Slave Interface (4 Channels) Hardware Specifications Parameter Specification Model PLX31-MBTCP-MBS4 Brand ProSoft Technology Origin USA Weight 0.46 lbs Dimensions 13.67 x 5.05 x 11.13 cm Operating Temp -25 to 70 deg C (-13 to 158 deg F) Storage Temp -40 to 80 deg C (-40 to 176 deg F) Relative Humidity 5% to 95% RH non-condensing Power Supply 24 VDC nominal (10 to 36 VDC range) Power Consumption 24 VDC @ 300 mA nominal, 10 to 36 VDC @ 610 mA maximum Ethernet Port 10/100 Mbit half-duplex, RJ45 connector Ethernet Isolation 1500 Vrms at 50 to 60 Hz for 60 seconds (IEC 60950: 1991) Serial Ports 4 isolated serial channels Serial Isolation 2500 Vrms signal isolation per UL 1577 (SiliconLabs Si844x RF technology) Shock Ratings IEC 60068-2-27; 15G @ 11ms (Operational), 30G @ 18ms (Non-Operational) Vibration Ratings IEC 60068-2-6; 5G @ 10 to 150 Hz LED Diagnostic Indicators CFG, ERR, PWR, FLT, NS, MS, Link/Act, Serial RX/TX Industrial Network Isolation & Protocol Conversion Latencies The PLX31-MBTCP-MBS4 incorporates high-speed RF-based digital galvantic isolation circuits across all four serial ports, utilizing SiliconLabs Si844x isolation components to achieve 2500 Vrms port-to-port and channel-to-ground dielectric protection. This isolation architecture prevents ground loop currents and transient voltage spikes from propagating between field-mounted Modbus serial devices and the upstream Modbus TCP/IP Ethernet backbone. Protocol conversion latencies are minimized through an internal optimized memory map, enabling high-throughput data transfer between Ethernet buffers and serial UART transceivers without degrading deterministic poll cycles or causing packet collisions during multi-master polling operations. Frequently Asked Questions Q: How does the gateway handle high-volume broadcast traffic on the Ethernet interface? A: The physical Ethernet controller implements hardware-level Broadcast Storm Resiliency. It restricts incoming Address Resolution Protocol (ARP) frame processing to a maximum rate of 5000 frames-per-second for durations up to 5 minutes, ensuring internal CPU resources remain dedicated to protocol execution during network flooding events. Q: What physical isolation mechanism is deployed on the serial communication channels? A: Each of the four serial ports utilizes SiliconLabs Si844x series digital isolators based on RF (Radio Frequency) modulation technology. This yields a 2500 Vrms signal isolation rating per UL 1577 between individual serial channels and internal logic circuits. Field Installation Guidelines DIN-Rail Mounting & Enclosure Clearance: Secure the module on a standard 35 mm DIN rail in an vertical position inside an IP54 or higher industrial enclosure. Maintain a minimum top and bottom thermal clearance of 50 mm to facilitate natural convection cooling across the temperature operating range of -25 to 70 deg C. Grounding & Shielding Execution: Connect the designated GND terminal on the power connector directly to the nearest low-impedance protective earth (PE) busbar using a short 14 AWG conductor. Connect serial communications cable shields strictly at one ground point to avoid circulating ground loop currents. Power Supply & Wiring Limits: Wire the primary 24 VDC supply using copper conductors rated for at least 85 deg C. Ensure the power source output capacity accommodates the maximum inrush and steady-state current draw of 610 mA at the lower 10 VDC input threshold.