---
lang: "en"
title: "MR-RO-1: 1-output RELAY MODBUS Module"
sku: "FF-MR-RO-1"
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brand: "MARCOM S.r.l."
end_of_life: "false"
---

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FF-MR-RO-1: 1-output RELAY Module

The MR-RO-1 module is used as an external device that extends the relay outputs of programmable logic controllers (PLCs) or other devices where data is exchanged via the RS-485 port using the MODBUS RTU protocol.

## Technical Features

- 1 isolated NO / NC contact
- ON / OFF control
- Output status
- Timer control options: 

- delayed activation
- delayed activation for a preset time
- cyclic ON / OFF operation
- cyclic OFF / ON operation
- Memory of state after power interruption
- Automatic start of time function
- Time of last output switching
- Number of output switchings
- Number of cycles performed for time functions

#### Operation

The MR-RO-1 module is equipped with a controllable relay output (isolated contact). The output operates according to the preset operating mode and its assigned parameters. The setting and reading of the output status, operating parameters, and the adjustment of all communication and data exchange parameters are done via the RS-485 port using the MODBUS RTU communication protocol. Power is indicated by a green LED light. Proper data exchange between the module and the other device is indicated by the yellow Tx LED.

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Source: https://shop.marcomweb.it/en/remote-io/mr-ro-1-1-output-relay-modbus-module

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