In this project we look at how to control a Ceiling Fan that allows for standard rotary switch control and doesn't require an automation controller to coordinate multiple Z-wave switches through scenes.
One of the principles I apply to any project is that your device should continue to be operable in an intuitive way that doesn't require a smartphone. In other words the automation should enhance, not replace, familiar control schemes that can be used by visitors, kids or the people you eventually sell your house to.
For ceiling fans, this means being able to use the common rotary switch interface that sits on the wall. This project provides a means of maintaining fan operation independent of the automation controller, while still giving full automation control over the fan.
Disclaimer - this project involves high voltage electricity. The project demonstrated here was powered by a 240VAC inverter connected to SLA Batteries. The GOAP Dimmer and Digital Relay modules are 24VDC devices. The wiring diagrams are examples only and it is the responsibility of the installer to validate and confirm the wiring, applicable safety standards and regulations that apply to all components. All domestic 240V wiring must be performed by a licensed electrician.
- Fan can be operated via wall control using a 4 position 360 degree rotary switch or Potentiometer which translates to 3 speeds.
- Support for OFF-HIGH-MED-LOW and OFF-LOW-MED-HIGH control schemes for fans which require high startup current.
- Wall control works even if the automation controller is offline.
- Hardware based Digital Relay control ensures correct non-crossover switching with configurable delay.
- Uses the existing Fan speed capacitor to maintain existing speeds with no motor hum.
- Interface on controller as a standard dimmer or using a Vera Plugin which provides a Fan interface, configures the Z-wave Module and updates fan status if activated from the wall control.
The initial version of this fan controller requires a rotary switch that turns full 360 degrees continuously. That is because the OFF position effectively becomes the HIGH speed, and HIGH is effectively OFF. This means that rotating the switch mechanism 90 degrees to the knob makes the existing speed markers line up.
This won't be possible if you have a switch that only goes from left to right positions and not full turns.
Alternately, you can use a potentiometer to provide the speed control. It will still translate to OFF and 3 speeds via the relays, but obviously lacks the tactile "click" the rotary switches have.
Of course there's no obligation to have a wall switch to work with this setup. If you don't have an existing wall switch, don't want to wire one up and want to use a Z-wave remote, or voice control by Amazon Alexa that's not a problem either.
In this example we used:
- 3 Stage Digital Relay Module*
- GOAP 0-10V Z-wave Dimmer
- The LiveHouse Fan Control Plugin (Optional)
- Fan Speed control capacitor
- Fan Rotary Switch with 360 degree rotation or a 100k Potentiometer
- 24V DC Power Supply
- 15k and 47k resistors (if using rotary switch)
- Hookup wire and optional screw terminals
- Plastic Enclosure or Project Box
*Important note: In this project we switched our test bench 240VAC supply through the relay contacts as a proof of concept. However, these relay modules are not Australian certified for use with voltages exceeding 50VAC or 120VDC and should be used as dry contacts for control switching. For domestic use, consult your electrician regarding the use of appropriate external contactors or relays if you need to directly connect to or switch mains power for an AC fan.
In this video we demonstrate how the fan switching works in practice from the wall control and how it appears on the Vera Controller using the LiveHouse Fan Plugin.
- Can I control a 6 speed Fan?
Yes, if you connect 3 speeds. If you really need 4,5 or 6 speed control we can get Digital Relay Modules that have extra relays.
- Will this work on Z-wave Controllers other than Vera?
Yes, the GOAP Module shows as a standard dimmer. You won't be able to use our plugin, but that doesn't stop you controlling the dimmer directly via scenes.
Wrapping it up
As you can see, this is a very flexible solution that can be adapted to almost any application that needs to emulate a 4 position switch/control scheme. You may also note that the relay modules support other operating patterns such as Heat/Cool or cumulative Sequence which makes them suitable for controlling Airconditioners, Heaters and other devices with different switching patterns.