> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# Modbus RTU 32-Ch Relay Module

**Type:** Product page · **SKU:** WS-25140 · **Brand:** [Waveshare](https://core-electronics.com.au/brands/waveshare-in-australia)
**Page:** https://core-electronics.com.au/modbus-rtu-32ch-relay-module-rs485-industrial-grade.html ([markdown](https://core-electronics.com.au/modbus-rtu-32ch-relay-module-rs485-industrial-grade.html.md))

Modbus RTU 32-Ch Relay Module, RS485 Interface, With Multiple Isolation Protection Circuits, Industrial-Grade, Rail-Mount Case

## Pricing

- **Price:** $119.95 (inc GST) — $109.05 AUD, exc GST
- **Quantity discounts:** 5+ $104.68 (exc GST) · 10+ $101.41 (exc GST)

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 2 today, and up to 300 more in 12–19 days.

## How to buy

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## Description

This product is an industrial 32-ch relay module controlled via RS485 bus, adopts Modbus RTU protocol, built-in protection circuits such as power supply isolation, magnetical isolation, resettable fuse, and TVS diode, etc. It also comes with an ABS case.

The Modbus RTU 32-Ch Relay is very easy to use. Due to its fast communication, stability, reliability, and safety, it is an ideal choice for industrial control equipments and/or applications with high communication requirements.

### Features

- Configurable device address (1~255), multi devices can be cascaded on RS485 bus
- Features flash-on, flash-off function, it is possible to turn on the relay for a while and then close it automatically via the command
- Onboard voltage regulator chip, supports 7~36V wide voltage power supply
- Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal
- Onboard unibody magnetical isolation, allows signal isolation, high reliability, strong anti-interference, low power consumption
- Onboard resettable fuse and TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, provides over-current/over-voltage proof, lightningproof & anti-electrostatic
- Onboard Optocoupler isolation, prevent the relay from being interfered by high-voltage circuit
- Onboard dedicated relay driver chip, with built-in freewheeling diode protection, the driving ability is stronger and more stable
- Reverse-proof circuit, prevent the circuit from being damaged accidentally by incorrect connection
- High quality relay, contact rating: ≤10A 250VAC/30VDC
- Rail-mounted ABS case, easy to install, safe to use
- 3 LEDs for indicating the MCU status and signal transceiving status

### Specifications

| Operating voltage | 7~36V |
|---|---|
| Communication interface | RS485 |
| baudrate | 4800, 9600, 19200, 38400, 57600, 115200, 128000, 256000 |
| Default communication format | 9600, N, 8, 1 |
| Relay channels | 32 |
| Contact form | 1NO 1NC |
| Contact rating | ≤10A 250VAC/30VDC |
| Communication protocol | Standard Modbus RTU protocol |
| RS485 address | 1~255 |
| LED indicators | STA: MCU indicator, keep flashing when the MCU normally working TXD: TX indicator, lights up when sending data RXD: RX indicator, lights up when receiving data |

### Dimensions

![](https://core-electronics.com.au/attachments/localcontent/Modbus-RTU-Relay-32CH-details-size_194093449cb.jpg)

### Resources

- Wiki for Modbus RTU 32-Ch Relay Module

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/W/S/WS-25140-2.jpg)