ESP32LR42
User Manual v1.02
Overview
The ESP32LR42 is a WIFI connected relay module using the popular ESP32.
It provides 4 relays capable switching up to 16Amps and 2 digital inputs with pull-ups than can
interface directly with volt free contacts. The normally open relay contacts have snubbers fitted across
them, and can drive inductive loads such as contactors and solenoids.
Power for the board is 12v dc, which can be provided by a standard universal wall power supply. A 1A
or greater supply should be selected.
Control Protocols
1. Simple plain text commands sent to the module.
2. HTML commands
3. MQTT
4. A built in webpage
WiFi
The ESP32LR42 connects via WiFi to your network. Therefore it must be located in a position where it
gets a good WiFi signal. The module should not be enclosed in a metal box/cabinet as this will shield
the WiFi signal.
You can check the signal level by looking at the RSSI figure which is reported by the ST (STatus)
command.
Configuration
The ESP32LR42 is configured by connecting a USB cable to your PC and running a terminal program.
PuTTY is a good option if you don’t have any other preferences.
The serial port should be set to 115200 baud, 8 bit, 1 stop, no parity, no flow control.
Copyright
© 2018,
Devantech Ltd.
All rights reserved.
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