RIO-15C I/Os

Terminal Strip Connections

RIO-15C devices connect to power and user signals via three green, screw-terminal connectors. Each pin on these connectors is labelled on the connector's front face:

AI-1, AI-2, AI-3, AI-4

analog inputs; Each input is capable of measuring a signal from 0 to 20mA. The module presents a 250Ω load on each input.

GND

ground; Negative DC power for the RIO device and electrical reference point for all inputs and outputs. All ground pins are tied together internally.

AO-1, AO-2

analog outputs; Each output is capable of driving from 4 to 20mA into a 250Ω load.

DO-1, DO-2, DO-3, DO-4

open collector, digital outputs; When the associated DO LED is lit, the output is pulled to ground. Each output is rated at 200mA max.

DI-1, DI-2, DI-3, DI-4

optically-isolated digital inputs; These inputs are pulled high internally, and suitable for connecting to most Form A or TTL outputs.

485+

positive RS-485 signal

485-

negative RS-485 signal

RTS

ready to send; a high signal indicates that the RIO-15C needs to send data

TXD

transmit data, from the RIO-15C to the user device

RXD

receive data, from the user device to the RIO-15C

CTS

clear to send; pulled high to indicate that the RIO-15C may send data

V+

positive DC power for the RIO device; Both pins are tied together internally.

Most installations do not require hardware handshaking. In such cases, you can connect the CTS pin directly to the RTS pin, or disable handshaking with the configuration utility.

Digital Inputs

Digital inputs should be driven to ground to signal "on".

Use a Debounce value of 75 for mechanical inputs and a Debounce value of 0 for digital inputs.

Digital Outputs

RIO-15C outputs are pulled to ground when "on". They can sink up to 200mA. Here is a typical configuration that uses the output to control a user load:

Analog Inputs

Analog inputs can sense a range of 4 to 20 mA. Here is a typical configuration that uses the analog input to monitor the current through a sensor.

Analog Outputs

Analog outputs can drive a range of 4 to 20 mA into a 250Ω load.