3Wire RS2S2 is an isolated dual-slave RS-485 hub designed to extend one RS-485 bus into two reliable protected output interfaces. It is built for harsh industrial, outdoor and long-distance communication environments where normal RS-485 wiring can become unstable.
For IoTWatt 4.0 projects, RS2S2 helps strengthen the field communication layer between power meters, sensors, gateways and existing BMS / EMS / SCADA systems. It supports more reliable Modbus RTU data collection for energy dashboards, digital energy audit evidence, EECA reporting and operational analytics.
RS-485 networks are commonly used for Modbus power meters, PLCs, sensors, controllers and remote monitoring devices. However, when the network is long, branched, outdoor, noisy or exposed to grounding problems, communication can become unstable.
RS2S2 provides a practical way to strengthen the RS-485 network by creating two isolated output branches from one input bus. This helps improve communication stability, segment the field network and reduce the impact of electrical disturbances on connected devices.
RS2S2 is best positioned as an industrial RS-485 branch hub for energy monitoring, automation, utility metering, outdoor communication and IoTWatt 4.0 retrofit projects where reliable data collection is critical.
IoTWatt 4.0 depends on reliable field data. RS2S2 helps protect and stabilise the RS-485 communication layer so that energy meters and sensors can provide consistent data to gateways and analytics platforms.
Extends one RS-485 input bus into two output interfaces for safer and cleaner network expansion.
Built-in optoelectronic isolation provides up to 2,500V RMS isolation for protected communication.
Each RS-485 line is protected with 600W lightning and surge protection for industrial environments.
High ESD protection helps reduce failure risk during field wiring and harsh operating conditions.
Automatically detects RS-485 data flow direction and switches communication direction accordingly.
Supports RS-485 transmission distance up to 3,000 metres, depending on baud rate and site conditions.
RS2S2 can be used when one RS-485 trunk needs to be branched into two isolated RS-485 output channels. This is useful when meters or devices are physically located in different panel sections, equipment rooms, buildings or outdoor areas.
For larger networks, multiple RS2S2 hubs can be used in parallel, subject to proper RS-485 design, baud rate selection, grounding, shielding, termination and device loading. The original datasheet indicates that up to 128 RS-485 hubs can be connected to the RS-485 bus in parallel, depending on network design and site conditions.
For energy monitoring and IoTWatt 4.0 projects, RS2S2 is most useful where RS-485 communication reliability is more important than simply adding more wiring. Good network design, termination and shielding are still required.
| Interface | Terminal | Function |
|---|---|---|
| Input Side | 485B | RS-485 negative input |
| Input Side | 485A | RS-485 positive input |
| Input Side | V- | Power ground |
| Input Side | V+ | 9-40VDC power input |
| Output Channel 1 | 485A1 / 485B1 / GND | First isolated RS-485 output channel and isolated ground |
| Output Channel 2 | 485A2 / 485B2 / GND | Second isolated RS-485 output channel and isolated ground |
| Parameter | RS2S2 Specification |
|---|---|
| Product Type | Dual-slave isolated RS-485 hub / RS-485 branch protection hub |
| Standards | RS-485, EIA / TIA compliant |
| RS-485 Input | 4-pin terminal block |
| RS-485 Output | 6-pin terminal block with two RS-485 output channels |
| Transmission Media | Twisted-pair or shielded cable |
| Communication Mode | Asynchronous half-duplex |
| Power Supply | 9-40V DC, 500mA |
| Indicators | LED indicators for Power, Transmit and Receive |
| Isolation Voltage | 2,500V RMS; 500V DC with DC/DC isolation module |
| Baud Rate | 300 bps to 115.2 kbps |
| Protection Features | 600W lightning and surge protection per RS-485 line; ±15kV ESD protection |
| Transmission Distance | 0 to 3,000 metres, dependent on baud rate and site conditions |
| Parallel Hub Expansion | Up to 128 RS-485 hubs can be connected to the RS-485 bus in parallel, subject to network design |
| Dimensions | 80 x 50 x 31 mm |
| Operating Temperature | -40°C to +85°C |
| Relative Humidity | 5% to 95%, non-condensing |
Improve Modbus RTU meter communication reliability for energy dashboards, reports and analytics.
Branch RS-485 networks for power meters, water meters, gas meters and remote utility devices.
Improve communication reliability between PLCs, controllers, sensors and field devices.
Support RS-485 communication expansion for building automation and supervisory systems.
Support distributed RS-485 wiring exposed to outdoor cable routes, surge risk and grounding differences.
Useful in factories, MCC rooms, pump rooms and electrical rooms with noisy field communication conditions.
RS2S2 supports IoTWatt 4.0 by improving the reliability of RS-485 field communication. This is especially important when the site already has existing Modbus meters, long RS-485 cable runs, noisy electrical rooms or distributed panels that need to be connected to a digital energy audit platform.
| IoTWatt 4.0 Use | How RS2S2 Supports It |
|---|---|
| Energy Dashboard | Supports more stable data collection from RS-485 power meters and field devices. |
| Digital Energy Audit | Improves reliability of load profile data used for audit evidence and analysis. |
| EECA Reporting | Helps maintain communication continuity for meter data required in regulatory reporting workflows. |
| Retrofit Projects | Useful when existing RS-485 networks need to be reused instead of replacing meters or cabling. |
| Gateway Protection | Provides isolation and protection between field wiring and upstream IoTWatt gateway devices. |
Use RS2S2 as part of the IoTWatt 4.0 field connectivity layer when meter communication reliability is affecting dashboard data, energy audit evidence, EECA reports or savings analysis.
The diagram below shows the RS2S2 dual-slave RS-485 hub operation, bus extension and isolated branch interface arrangement.
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RS2S2 dual-slave isolated RS-485 hub operation diagram
Saturn Pyro supports 3Wire RS2S2 isolated RS-485 hubs for Modbus meter networks, BMS / EMS / SCADA integration, IoTWatt 4.0 digital energy audit projects, EECA reporting data collection and industrial RS-485 communication reliability improvement in Malaysia.
Malaysia
