It is possible to use a single ESP32 to handle multiple relays in your IoT project. We can use MQTT to subscribe or publish multiple topics. A good real-life deployable example of IoT controlled AC appliances is our guide on . In that project, we have two status indicator LEDs and one relay connect to the ESP32. We could control the AC appliance connected with the relay either by pressing a … [Read more...]
Archives for September 2019
How to Control Multiple Relays With Single Arduino ESP32?
One regular reader of this website asked us how we can control multiple relays with single Arduino ESP32? This article will not give any direct answer. This is a theoretical article discussing how multiple channels on MQTT can be created so that we can separate matters like temperature and humidity from a DHT11 sensor. Normally we connect DHT11 with IBM Watson IoT in a raw manner. In our that … [Read more...]
ESP32 Arduino AC Motor Speed Control Module/Circuit
So far, we have shown how to control ON/OFF status of an AC powered appliance with IBM Watson IoT. That guide is important to use HTTP(S) POST request instead of using MQTT. HTTP POST and MQTT has difference of use-case. In this present article, we only restrict ourselves to discussions around ESP32 Arduino AC motor speed control module and circuit. Using an AC appliance for switch ON and … [Read more...]