Ceiling Fan Control

Can some tell me if they is such a device that allows ceiling fan speed and direction control via C-bus?
If so is it a C-Bus device or is it done with a relay module and discrete capacitors?

DDirk

 

There is no native C-Bus device dedicated for ceiling fans. Most people do it using the supplied capacitor block wired into a few channels on a standard relay and then using either logic or interlocking to link the channels together.

 

Fan Direction

Thank you Newman,

I take it that to change direction on a single phase fan will require a double pole c/o relay and the rewiring of the stator windings?

Rgds
DDirk

 

It would certainly not be a simple job. Your best bet is probably to buy a fan that has a direction selector switch on it, and then wire that switch out externally (will require some mods) to a change-over relay so that you can flip the direction.

 

What good timing, just bought a fan and was going to do the reversing as well through C-bus (it does have a switch on it so I can wire that out).

I will preface this by saying that I have never wired up a fan, the instructions are absolutely crap.

I think it is like this
Speed 1 - no cap
Speed 2 - cap 1
Speed 3 - cap 2 (it could be the other way around though)

Code:

                     1.75uf
              |-----||--------- (2)
      (1)-----|
              |-----||--------- (3)
                     3.5uf

My question is, if I use a standard relay unit (not change over), one for each speed, what is the result should all three channels come on.

I suspect, that all three relays on would be slow speed (ie the cap is bypassed).

If only relays 2 & 3 came on, I think I would get a fourth speed - even faster than speed 3 (cap1 & cap 2 in parallel giving a new capacitance = 5.25uf), or will I damage the motor.

It would be great to see a small ceiling fan controller, similar size to the blind relay, with reversing functions as well.

Mick

 

DDirk

Newman is correct, in europe we use lots of ceiling fan in both direction
and to control it via an automation system is a pain.

Normally one stator is permantly wired and the other is switched,
you have to bring out all motor winding wires out and switch both with a
2 pole change over relay (as you said) that is then operated via your automation system, and is best reduced to zero speed before you change direction.

Tyrone

 

You can have 4 speeds as shown below

Speed 1 - no cap
Speed 2 - cap 1
Speed 3 - cap 2
Speed 4 - cap 1 & 2 (these are in parallel to each other)

Tyrone

 

Ceiling fans are wired so that a capacitor is in series with the fan motor at slower speeds. Full speed connects the motor directly to the mains. You cannot get more power to the motor than mains allows by just connecting a capacitor in series.

Off - Open Circuit
Low - Weedy tiny capacitor letting through a little current
Medium - Beefy capacitor letting through more juice
High - Motor connected directly to mains.

If you connected the two capacitors in parallel with each other, to the motor, you'd get a sort of Medium+ speed, a bit faster than Medium, but not as fast as High.

A number of the manufacturers use dedicated capacitor blocks, where the weedy and the beefy capacitors are inside a common package with one terminal of each connected together.

 

Well, actually you can in theory. If you add just enough capacitance to resonate with the motor's inductance at mains frequency, then the motor windings will see higher than normal voltage and the fan can actually run faster than with no capacitor.

Fortunately, fan motors are typically quite lossy so the 'Q' of any resonant circuit is not very high. High voltages might result in premature failure of capacitors or insulation so if in doubt, I would suggest monitoring the voltage across the capacitor (or the fan motor) to make sure all is within manufacturer's specifications.

I use the same arrangement as Tyrone suggests, and have for years without any problems. It gives me off, plus three distinct and useful speeds.

 

Fan Speed

Tyrone is right in what he has said,

However there are things to consider as Don indicated.

The Voltage across the caps / use good quality motor run caps not motor start.

Do not exceed the manufactures capacitance rating for the motor
so if the maximum is say 5uF then use 2uF, 3uF and both as 5uF.

There is no problem doing this.

Cheers
Automan

 

Thanks for the clarification.

There is a capacitor block, it has two caps in it (three wires) so it is feasible to run two in parallel. As long as a failure of logic wont cause an issue (ie 2 or three channels on) then there is no need for hardware protection.

Mick

 

Fan Control

"edited extract from training manual"

Fan control is commonly wired a programmed a number of different ways. In this exercise we will use fan
speed capacitors wires into a relay to control the fan. So consider that the fan was wired as shown in the figure
below.

Group Address " Fan "

12 Ch Relay
Ch 1 - Fan
CH 2 - Fan
Ch 3 - Fan


To program C-Bus to operate in this configuration, follow the steps below.
1) Open the 12 channel relay and click on the Turn On tab.
2) Change the Interlock Channels parameter to 3.
3) Configure the Turn On Threshold of Channel 1 to 0%.
4) Configure the Turn On Threshold of Channel 2 to 30%.
5) Configure the Turn On Threshold of Channel 3 to 70%.
6) Set Group Address to Fan on channels 1, 2 and 3
7) Click the OK
8) In the Input units set the Group Address ?Fan? to be a Dimmer

Credits : CIS

Personally for me though....
I prefer to wire the fan directly from the relay ( cbus on / off )
the fan crontroller is the located in the
nearest WIR Cupboard etc... (speed control)

Have 4 Fans at my place and all have been on 2nd speed for the last 2 1/2 years.....

Cheers All

 

Hi Ashleigh,

In my case about 98% correct. I manually switch our lounge fan to pos 2 in the wet season here (FNQ) but all other fan are set and forget. All speed controllers are buried in WIR, robes, closets etc so they are not an eye sore. C-Bus control the on off.

I went through all the options and chose the KISS system and it works great...I get my wife to do the switch to Pos 2 and back to 1 at the end of the wet season!! Sweet.........!

Regards,

Fleetz

 

I'M curious as to why you cant simply use a dimmer channel??

 

Hum

 

That must be the shortest complete post I have seen!

To elaborate: The problem with using dimmers for fans is that the motor windings will vibrate from the switched voltage from the dimmer. You will be able to hear a hum or buzzing noise.

 

I couldn't waste such a good opportunity

Besides, most of my responses are long-winded, so this goes a little towards balancing my contribution.

 

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