Product overview and engineering role
The SimtoLink Modbus RTU-to-TCP gateway maps RS485 and RS232 slaves on the floor to a Modbus TCP server or client on Ethernet. Concurrent masters, serial routing, and slave-ID translation are included. On building, energy, and plant sites it is the usual first hop when a serial protocol has to reach the cloud.
Point tables can be imported in bulk, and timeout and retry templates are supplied. TLS and an IP allowlist are available on the models that include them. DIN-rail and wall-mount builds, and wide-temperature versions, can be specified for the job.
Reliability and field fit
On electrical safety and EMC, this gateway has cleared the relevant CCC test items. Ports include surge and reverse-polarity protection. Reinforced grounding and a partitioned layout cut ground-loop and common-mode risk. Outdoor or coastal orders can take a higher ingress rating and a corrosion-resistant coating.
Parameters import in bulk, with threshold policies and event video or waveform capture on the models that support them. Configuration and firmware go out over OTA. SimtoLink recommends a three-step site acceptance: power-on self-test, communications time sync, and a sample check. For metering or safety-related use, SimtoLink can help with a third-party metrology submission and type-test documents.
Key hardware parameters
The figures below are the hardware ratings for a typical build of this gateway, written so they can go into a selection note or a tender clause. For a wider range, redundant power, or an intrinsically safe explosion-proof variant, ask SimtoLink for the hardware specification and the installation and commissioning guide. Order numbers in this family can differ slightly; the nameplate and the papers packed with the unit govern.
| Parameter | Specification | Notes |
|---|---|---|
| CPU | ARM Cortex-A55 quad-core | Fanless |
| Memory / storage | 4G/32G eMMC | Industrial grade |
| Ethernet | Single GbE | Redundant RSTP |
| Serial | 8×RS485 | Isolation 2.5kV |
| Wireless | Wi-SUN | External antenna |
| Protocol stack | BACnet/IP | Expandable |
| Operating temperature | -24～63 ℃ | Wide temperature |
| Power | PoE+ | Redundant terminals |
| Mounting | DIN rail | Grounding required |
| Security | TLS1.2 | Firmware signature check |
Typical applications
Ways this gateway is usually installed on site, for choosing a scheme and checking the integration:
Legacy meters onto Ethernet
Electricity, water, and gas meters stay on Modbus RTU. The gateway gives EMS and BMS one TCP outlet.
Data-center power and environment
UPS, cooling, and PDU serial devices join the IP network so an NMS can poll them and fold alarms together.
Production machines on the plant network
Injection-molding machines, welders, and other serial-only machines reach the plant OT backbone through the gateway, so fewer USB converters stay on the line.
Installation, grounding, and maintenance
- Confirm supply range and polarity before power-up. If the reading is in doubt, check bus voltage and breaker rating with a multimeter.
- Run communications on shielded twisted pair, grounded at one end, and do not bundle it with high-power cables over a long run.
- For the first go-live, finish two-way read and write plus threshold-trigger checks against the platform in the lab, then move the unit to site.
- Outdoors, drainage and ventilation come first. Inspect sealing faces on a schedule, and keep lightning-protection ground resistance inside the local code.
- On a long-running site, sample-check the gateway and archive logs every 6 months.
Ordering, documentation, and support
SimtoLink ships a hardware specification, outline drawings, a wiring table, and a sample project for this gateway. Volume orders can include a sample review and an inspector at the factory. Warranty and calibration terms are those in the contract and in the papers that travel with the unit.
Related reading
Pages in the same folder, for pairing a serial port with a northbound IoT link: