Connect your RS-485 and RS-232 field devices to a live industrial dashboard from any browser. Real-time monitoring, alarms, and historical trends — without replacing your RTU infrastructure.
No credit card · RS-485 / RS-232 support · RTU + TCP in same platform
Modbus RTU is the serial variant of the Modbus protocol — it runs over RS-485, RS-232, or RS-422 cabling and is used in legacy PLCs, energy meters, variable frequency drives (VFDs), sensors, and remote I/O modules worldwide. Despite being a 40-year-old protocol, Modbus RTU devices still make up the majority of field instruments in many industrial plants.
Modbus RTU SCADA connects these serial field devices to a modern cloud monitoring platform. SCADA Cloud uses a lightweight serial gateway — a small service running on a local PC or Raspberry Pi — to poll your RS-485 bus and securely forward tag values to the cloud. You then view live dashboards, configure alarms, and analyze historical trends from any browser, anywhere.
No need to replace your existing Modbus RTU infrastructure. The gateway bridges the gap between legacy serial devices and modern cloud monitoring — giving you remote visibility without ripping out the serial bus.
Built to handle legacy serial devices at scale
Connect via any COM port or USB-to-RS485 adapter. Configure baud rate (1200–115200), parity, data bits, and stop bits to match your field devices.
Poll up to 247 slave Unit IDs on a single RS-485 bus. Define individual register maps per device — different addresses, different register counts, different data types.
Holding registers, input registers, coils, and discrete inputs from all your RTU devices appear as live tags on a configurable HMI dashboard in your browser.
Set high/low/deadband alarm rules on any RTU tag. Receive instant email or SMS alerts. Operator acknowledgement and alarm history log included.
Every tag value is timestamped and stored automatically. Query historical data, export to CSV, and overlay multiple tags on a trend chart for process analysis.
Mix Modbus RTU serial devices with Modbus TCP Ethernet devices on the same dashboard. No separate SCADA systems — one platform for all your Modbus infrastructure.
Because Modbus RTU runs over physical serial cables, it cannot connect directly to the internet. SCADA Cloud uses an edge gateway approach — a lightweight service that runs on-site and bridges the serial bus to the cloud.
Run the SCADA Cloud gateway service on any Windows or Linux PC connected to the RS-485 bus via a USB-to-RS485 adapter or native serial port. Install takes under 2 minutes.
In the SCADA Cloud dashboard, add each RTU slave by Unit ID, baud rate, and register map. Specify which holding registers or input registers to read and at what polling interval.
The gateway polls your RTU bus and streams data to the cloud over HTTPS (outbound only — no inbound ports to open). Log in to your SCADA dashboard from any browser, tablet, or phone to see live register values, trends, and alarms.
Any RS-485 device that speaks Modbus RTU works with SCADA Cloud
Monitor kWh, V, A, PF, and Hz from Modbus RTU energy meters. Popular brands: Eastron, ABB, Schneider PM series, Chint, and Carlo Gavazzi. Read all standard energy register maps.
Monitor VFD output frequency, motor current, fault status, and setpoints over RS-485. Supports ABB ACS, Siemens G120, Danfoss FC, Schneider Altivar, and other Modbus RTU drives.
Legacy PLCs from Siemens, Allen-Bradley, Mitsubishi, Delta, and Omron often have RS-485 Modbus RTU ports. Connect them to SCADA Cloud without upgrading to Ethernet-equipped hardware.
Temperature, humidity, pressure, CO₂, and gas sensors with RS-485 Modbus RTU output. Common in HVAC, cold chain, cleanrooms, and building management applications.
Flow transmitters, ultrasonic level sensors, and pressure transducers with Modbus RTU output. Used in water treatment, chemical processing, and oil & gas applications.
Many solar inverters expose Modbus RTU registers for AC/DC voltage, current, power, and fault codes. Compatible with SMA, Growatt, Sungrow, Fronius, and other brands using RS-485.
| Parameter | Values | Notes |
|---|---|---|
| Baud Rate | 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 | Must match all devices on bus |
| Parity | None (N), Even (E), Odd (O) | Most devices default to None |
| Data Bits | 7 or 8 | Almost always 8 |
| Stop Bits | 1 or 2 | Usually 1 |
| Unit ID | 1–247 | Unique per device on bus |
| Register types | Coils (0x), Discrete Inputs (1x), Input Registers (3x), Holding Registers (4x) | All supported |
| Function Codes | FC01, FC02, FC03, FC04, FC05, FC06, FC15, FC16 | All standard FCs |
| Data types | 16-bit INT, 32-bit INT, 32-bit FLOAT, 64-bit FLOAT, BCD | Byte order configurable |
| Max bus length | 1,200 m at 9600 bps with termination | Shorter at higher baud rates |
| Max devices per bus | 247 (Unit IDs) | Practical limit ~30–50 |
Modbus RTU SCADA is a monitoring system that reads data from serial RS-485 field devices (PLCs, energy meters, VFDs, sensors) and displays it in a real-time cloud dashboard. SCADA Cloud uses a local serial gateway to poll the RTU bus and stream data to the cloud — no need to replace your existing RS-485 wiring or devices.
Yes. RS-485 serial cabling cannot connect directly to the internet. A lightweight gateway service runs on a local PC or Raspberry Pi, polls the serial bus, and forwards tag values to SCADA Cloud over HTTPS. The gateway only makes outbound connections — no inbound firewall ports to open. Setup takes about 10 minutes.
Yes. SCADA Cloud supports Modbus RTU, Modbus TCP, MQTT, and OPC UA on the same platform. A single dashboard can show values from legacy RS-485 energy meters alongside a modern Ethernet PLC and an MQTT IoT gateway — all on the same screen with combined alarms and trends.
Each RS-485 serial bus supports up to 247 slave Unit IDs (practical limit ~30–50 devices). You can run multiple gateways — one per serial bus or site — all reporting to the same SCADA Cloud account. There is no per-device fee during the 60-day trial.
Supported baud rates: 1200, 2400, 4800, 9600, 19200, 38400, 57600, and 115200 bps. Parity (N/E/O), data bits (7 or 8), and stop bits (1 or 2) are all configurable. Settings must match your device's factory defaults — most devices default to 9600, N, 8, 1.
Modbus RTU uses RS-485 serial cabling and requires a local serial gateway to reach the cloud. Modbus TCP uses standard Ethernet and can connect directly (device IP → SCADA Cloud). RTU is common in legacy field devices; TCP is standard for modern PLCs. SCADA Cloud handles both protocols so you don't need separate systems. See Modbus TCP SCADA for TCP-specific details.
Validate register maps before connecting to SCADA Cloud
60-day free trial · No credit card · RS-485 + TCP + MQTT in one platform
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