• SCADALink RIO900Low-Power Radio RTU Designed for I/O Telemetry and SCADA Applications.


SCADALink RIO900 I/O Telemetry Radio

The SCADALink RIO900 is designed to operate as Wireless IO, Wireless RTU, and Wireless  Modem System.

License Free 900 Mhz Wireless Point-to-Multipoint Communication

The RIO900 features license-free 900 MHz spread-spectrum radio technology providing a range of up to 20 miles.  Longer range can be achieved with RIO900 nodes configured as Repeaters.

SCADALink RIO900 Point to Multipoint Communications

Wireless I/O Telemetry

A key integral feature of the RIO900 is its wireless I/O signal replication mode (Figure 1).  In this mode, OUTPUT modules are paired to INPUT modules set at the same module address. The RIO900 supports replication of Digital I/O (contact closures) and Analog  I/O (4-20 ma) using AI/AO,  DI/DO, or COMBO-IO Pairs. The RIO900 supports both point to point and point to multi-point I/O replication.

Figure 1

RS232 & RS485 Interfaces

With both RS232 and RS485 interfaces, the RIO900 allows connectivity to field devices without additional interface converters, allowing multiple devices to be multi-dropped on the same COM port.

SCADALink RIO900: RS485 Multidrop

SCADALink RIO900: RS485 and RS232

Modular I/O Expansion

The RIO900 has an I/O Expansion bus which allows interfacing up to 10 SCADALink I/O Modules including the AI4, AO4, DI8, DO8, A8D4, & COMBO-IO  The I/O Modules can be easily bussed to the RIO900 via the I/O bus as shown below:


Wireless Modbus RTU Mode

The RIO900 can be configured with a Modbus RTU address and can be polled by a Modbus Master (Modbus RTU).

Low-Power Operation

The RIO900 is designed for Low Power Operation. The RIO900 enables SCADA communications to intelligent field devices with a minimal solar-power system. For applications with ultra low-power constraints, the RIO900 features a Power Off Mode operation where I/O modules and 24VDC Loop power is powerded down when not in use.


  • Secure factory configured network
  • Failsafe operation with configurable time-out
  • 2 serial interfaces (1 RS232 and 1 RS485 serial)
  • Integrated 900 MHz Radio
  • Failsafe Shutdown I/O modules
  • Interoperation with existing SCADA traffic


I/O Telemetry

Wireless I/O Telemetry

The RIO900 is designed specially to handle situations where I/O needs to be replicated from on site to another (Figure 1). The RIO900 System can handle both points to point  or point to multi-point configurations.

Figure 1 – Point to Point I/O Telemetry

Figure 2 – Point to Multipoint I/O Telemetry

Sometimes there is a requirement not only for Point to Point to Point but also Point to Multipoint Bidirectional Telemetry. PMP I/O telemetry systems is shown below. Inputs (1) are broadcast to Outputs (1), Analog Inputs (2) are replicated as Analog Outputs (2), Digital Inputs (3) are replicated as Digital Outputs(3).

Virtual I/O Mode

An RIO900 can be configured for Virtual I/O Mode where Modbus Registers of the RIO900 are mapped to I/O values of Virtual Output Modules as shown in Figure 2.  In this mode Remote I/O is mapped to predefined Modbus Register space in the target. This enables Modbus Masters such as an RTU/PLC Master or SCADA Master to use I/O points from an RIO900 based I/O telemetry System without connecting to actual I/O (Figure 3) . This saves on wiring and I/O hardware costs.

Figure 3 – Virtual I/O

Figure 2

Shutdown Systems:

RIO900 for Wireless Shutdown Systems


Wireless RS485

RIO900 for Wireless RS232/RS485 Extension

In addition to IO Telemetry Mode,  the RIO900 has RS232/RS485 Serial Communication where RS232 and RS485 serial ports in an RIO900 network appear as a multi-drop serial network.  In the RIO900 System, I/O Telemetry and serial communication can operate simultaneously. Figure 1 shows systems where serial communications can operate simultaneously as I/O Telemetry.

Figure 1


 Radio Communications
 Band 902-928 MHz LicenseFree
 Spread Spectrum (North America)
 915-928 MHz (Intl version)
 Tx Power 1 mW – 1 Watt
 Rx Sensitivity -110 dBm (@9600 bps)
 RF Data Rate 9.6 or 115.2 Kbps
 Range (LOS) >20 miles
 Antenna Connector SMA
 Input / Outputs 1 RS232, 1 RS232 / RS485
 Serial 1200 – 115,200 Baud
 Input Voltage +9 to 30VDC
 Power Consumption*
 Peak Tx Current(@24VDC) 105 mA
 Rx Current (@24VDC) 21 mA
 Operating Mode
 * – Does not include power consumption of I/O modules
 Operating Temperature -40 to 85 Deg. C
 Regulatory FCC,  IC, ETSI
 Hazardous Location Class 1 Div 2, Group C, D T3C
 Suitable for use in: Class 1 Zone 2, IIB, T3


Manuals & Datasheets

Application Notes



The RIO900 GUI is a windows-based application used to configure, save and restore all RIO family device settings. It is connected to the RIO device via serial cable to COM port.


The RIO900 can be configured for wireless data communication operation.




  • High Tank Level Shutdown
  • Water Tank Level Control
  • Pipeline Inlet Shutdown





Connection Example


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