FAN Sweep Control with Reverse Polarity

Hi All

I noticed some ceiling fans have a switch to reverse the direction of the fan.

Is it possible to use the cBus FAN Sweep Control with a Voltage Free Relay Unit to trigger the reverse direction of a ceiling fan?


Regards

Andrew

 

Theoretically yes. If it is a standard induction motor fan the reversing switch just reverses the direction of the second winding. You would need two cbus change over relay channels to accomplish this, plus a fair bit of rewiring (or just drive a separate double pole change over relay from a single cbus relay).

 

Think about this first though

Why is the switch on the fan body itself - so you cant reverse it while the fan is spinning. If you automate the reverse switch you can potentially reverse the fan while it is in motion and then who knows what will happen then!

 

Probably because that's the cheapest and easiest place to put it.

You would want to interlock it with the run relays.

Does seem an awful lot of trouble and expense for something you operate twice a year though.

 

I don't think interlocking would work. Lets say the fan is on high and you want to reverse it. You stop it, reverse it and then start it again. Interlock relays did what they were supposed to but that fan is still spinning with quite a bit of speed in the opposite direction for that little motor to try and stop and then spin the other way!!! That was the point I was getting at - having the switch above the blades ensures it has stopped before the change of direction can be made.

 

Well, the whole point of an interlock is to take all conditions into account. So if it is running, you stop it, wait however long required, reverse it, then start it up again. Not an uncommon control system. Change a running aircon from heating to cooling and see how long it takes.

 

Thanks for all your comments, The Idea for cbus to control the fans reverse, is so the home automation can start up ceiling fans in reverse mode when the air conditioning is on Heating. There is a bit of logic Id need to include, such as if the fan is on forward mode at the time the Aircon is switch on, to turn the fan off then wait for a period to allow the fan to slow down or stop. Then switch to reverse mode. When the room gets to the set temperature, the Home automation may turn the fans off... etc etc etc
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