Modbus RTU & TCP Gateway Sourcing from China
1 resources tagged with "Modbus Rtu Tcp"
Modbus RTU (serial, over RS-485) and Modbus TCP (over Ethernet) are the two transports of the same protocol, and a large share of China-made industrial gateways exist precisely to bridge them — taking RTU devices on a serial bus and exposing them as TCP to a SCADA system or an IEC 61850 substation gateway. The detail that trips buyers up is register mapping and slave-ID handling: a cheap gateway may not let you remap or buffer registers cleanly, so polling many RTU slaves over one TCP link gets slow or drops frames. We confirm the gateway's polling model and isolation before sourcing in volume.
An RTU-to-TCP gateway converts serial Modbus into Ethernet Modbus so legacy field devices reach modern controllers. The common pitfall is poor register remapping or weak RS-485 isolation; we verify the polling behavior and surge protection against the customer's slave count.
Cases (1)
FAQ
Can one gateway handle both Modbus RTU and TCP?
Yes — that is the typical job: it acts as a TCP server to the controller and an RTU master to the serial field devices. Confirm how many concurrent TCP connections and how many RTU slaves it supports, since cheap units cap low.
What certification do industrial Modbus gateways need for Europe?
CE with the EMC and LVD directives at minimum; for substation use buyers often require IEC 61850 or IEC 61131 compliance. Ask for the actual test report, not just a CE self-declaration.
Related Topics
Have a sourcing project in mind?
Tell us what you need. We respond within 24 hours, including weekends.