For my IoT home automation project I’ve chosen to use a Siemens LOGO!. This smart relay makes it possible to create a system that works on its own but can interact with the IoT world.
Typical applications of the LOGO! are automatic doors, traffic lights, basic heating/cooling/ventilation systems, pumps,…
Since version 7 the LOGO! has an Ethernet connection by default. This means that this relatively cheap unit is capable of controlling the light as it was build with teleruptors but with the power of network communication.
To program the Siemens LOGO! you’ll need the LOGOSoft Comfort software. Programming the LOGO! isn’t complex and actually fun and straight forward. (this opinion might be influenced by my automation/programming background)
The first thing that needs to be configured is the network on the Siemens LOGO!. After configuring the controller the settings can be downloaded to the device and an IP address will be assigned.
Because I want a setup that will make it possible to switch on lights even during network or server outage I’ll create a basic system that works with ordinary light bulbs and push buttons. This can be realized with the diagram below:
- I1 is a digital input, connected to the push button
- B001 is a ‘multiple function switch’, the default configuration of this block is OK for this application
- Q1 is the output to which the light is connected
Push the button and… huraay! light!
Listen to the outer world
Accepting a trigger from the outside (aka the network) is achieved by inserting an OR gate and connect a network input next to the switch input. The diagram now looks like this:
- NI2 is a network input connected to the local V memory V0.1
- B002 is an ordinary OR gate
You can test your ‘soft’ button using the Siemens app. This is free for a limited amount of inputs/outputs. The app is available for iOS and Android and can be found on http://w3.siemens.com/topics/global/en/industry/future-of-manufacturing/industry-apps/logo/pages/logo.aspx.
If you want automated triggers and create dashboards, buttons, alerts and other cool stuff you should definitely stay tuned for the article about connecting the LOGO! to Node RED.