One button blind control

I've got a job coming up and the client would like to control their blinds from a DLT unit. They would like to be able to use one button to control each blind. e.g:
press once - blind up
press again - stop
press again - blind down.

They will have a B&W C-touch controling them too.

Any ideas on how logic can help me here?

Thanks.

 

Hi SAC,

Have a look at this post from the logic code section of the forum.

http://www.cbusforums.com/forums/showthread.php?t=2283

This should help out a fair bit.

Cramer

 

Just be careful - if your motor controller needs both up and down on to stop then that code will not work for you.

Like all logic situations you need a very clear understanding of the functional flow before you start thinking about logic code.

If you need further help - you should explain the stop requirements. Also make sure you allow for a least 500mSec between driving your motor from one direction to the other again your logic can help here tied in with basic C-Bus functions (ramp and on thresholds in outputs)

 

Thanks Cramer / Phil.H.

Just not sure if that logic is right for me.

If I want to stop a blind say half way up, will this do that?

Signed, Confussed SAC.

 

You need to provide a bit of info on the blind motors you are thinking of using and if any sort of motor controller is involved ??????

Blind controls are not very hard but different hardware configs require very different controls.

If you are thinking of standard motors with some sort of basic electrical interlocking then there are a couple of options - let us know

 

Thanks Phil,

From what I've been told by the electrician installing the C-bus gear, they are somfy motors wired directly into 12 channel relays. Appearently, the owners don't want to install changeover relays due to cost. (disclaimer has been added to contract by electrician).

I have the same setup at home but my blinds are controlled by CTC's only.

I will be setting up a test board to try this out on seeing that there is only software interlocking on site. (Don't want to be the one that said I told you so!)

Thanks again Phil.H.

 

If it's a Somfy CD4 Controller connected to the motor, the changeover relay wont work anyway. This controller needs a up command and down command at the same time to stop the motor.

The simplest way is to have the common and up on one channel (i.e short between common and up sends blind up) and have the common and down on another.

Don't forget the B&W c-touch does not have Logic. I can't think of a way of doing it via one button other than logic however.

 

The best way to control any motorised device is to use three buttons - UP, DOWN and STOP.

 

Wow !

No electrical interlocking - pretty sure this one will end in tears. The electrician getting a disclaimer added to his contract should have woken up the client to the importance of this issue, more on that later. I would strongly recommend trying to get a least an aux relay in for each motor - one of the cheap plug in units that plugs into a din base providing a single change over set of contacts. Someone who puts C-Bus in then has expensive motorised blinds etc then won't spend a few bucks to protect their investment must have rocks in their head.

There are a few precautions you can take "in addition to interlocking". Make sure the local override buttons on the relay module are disabled. For this reason try to keep all the relay channels on the one unit. Make sure relay channels are programmed for "off" in power up options. Make sure there are no logic groups programmed for channels connected to motors and make sure no area address is programmed for relay units that have motors connected.

Now single button operation requiring up, stop, down, (three press functions) is going to be messy. A better solution will be a C-Bus button set up for "Timer" function with a time period a couple of seconds longer than it takes for the blind to travel its full range. Each time the button is pressed (GA on) trigger one of two scenes (via logic below) that starts with the opposite function - eg if it is the "up" scene then first function is to turn the corresponding down relay "off", Then ramp the ""up" relay on over 4 seconds. {Note - Program your relay channels with 15% on thresholds this will result in a little over half a second delay in the new channel turning on.} The ?down? scene is the opposite arrangement eg - up relay off - ramp down relay on over 4 seconds.

You then need an ?Off? scene. This is simply a scene with off commands for both channels. This scene is triggered directly from the GA on the button turning off. It will obviously turn off if the button is pressed a second time after being turned on or when the programmed time runs out. The beauty of using these scenes is other functions / processes can use them as well eg, good-bye or welcome programs etc.

The last thing is the toggle scene control based on the GA on the button, so you can use one button to alternate between the up and down scenes. The logic is simple ? to get the equivalent of a an alternating flag I used to increment a counter when the controlling GA is turned on. The counter counts 1, 2 then 3 goes back to 1 again. The counter for value 1 or 2 is a condition for which scene is triggered ? quick and simple. If any of the above makes sense drop a line and I will post some sample code

PS... Maybe the electrician can tell the client he is going to contact Somfy to find out if a motor does have power connected to both up and down circuits for a extended time, when the motor blows is there any chance of a fire hazard.

Hope this helps

 

Hello Pete

 

Thanks guys,

This is a very messy job. The client is very hard headed and seems to be getting advice from a 3rd party that seems to think they know it all. (University Computer Science Grad, related to the client). I think I might just walk away from this job now before I lose out big time later.

I have always programmed blinds with three buttons. It just makes sense.

Thanks again for all your help.

 

Phil,

From the information given to me from Somfy, if you use a CD4 controller, no interlocking is necessary, the worst that can happen if the channels are simultaneously turned on is that the blind will stop (not permanently ). If you're not using a CD-4 then that is another matter......

 

Chris,

You are correct a CD4 controller covers all issues regarding interlocking, however it does require a tricky up + down for a stop - no biggie, the somfy moduline bus controller is similar and as I said earlier, different hardware configs require different control options. There are several tried and tested C-Bus arrangements along these lines which we can give full info on if anyone wants it...

I think you will find from earlier posts in this thread that "the client" was not willing to pay for electrical interlocking relays let alone CD4 controllers.

 

On the Somfy Course there was a large topic on "Automation Control", and from their point of view a somfy controller should alway be used when connected to any kind of automation, and in fact I think they are getting their wholesalers to put a disclamer in if one isnt being used. Maybe you should get the guy to give Somfy a call. Otherwise this will end up with a client bagging out cbus without knowing all the fact. Or tell him to use the "Smart motors"

 

Ilt?

Hi Gents,

You guys seem to be the experienced blind automators, so im wondering if any of you have used/considered the Somfy ILT motors? They look like a nice solution to me, with seperate mains and LV control connections, removing the need for the CD4 controller.
This puts the electrical interlocking back into the hands of Somfy, so you should be able to get away with some simple software interlocking on C-Bus?

Any thoughts?

Cheers,
Mark.

 

Interesting, does that mean the Somfy switch would just go up in the ceiling if you connect C-Bus to it?

It looks like you have to have it connected for the limit switching.

 

ILT Limits

Hi,

As far as i can tell, the limits can also be set up in the motor by connecting the 'Electronic Limit Setting Tool' to the ILT motor. Once your limits are set, you are left with 3 wires: Up, Down and Common.

Cheers,
Mark.

 

Mark

is correct , you just need 3 wires up/down and common. , so they can be controlled by a cbus relay (2 channels) -change over/ interlocking not required, just a low voltage switch line

you can also parallel them up with out have limit problems (as the have built in electronic limits)

They can also have a mid way position, so at the press of one button all blinds can be made to got ot the same height etc .

 

Code for single button press

Howdy, Not reading through all the replies, but here is the code I have been using for a single button DLT press for blind control:

Code:

{Variables}
Bed3BlindMode : String;

{Initialisation}
Bed3BlindMode := "Close"; {First press will be a close}


once (GetLightingState("Bed 3 btn Blind") = On) then {the DLT button}
begin
  if (Bed3BlindMode = 'Close') then
    begin
      if (GetLightingState("Blind - Bed 3 up") = On) Then
      Begin
        SetLightingState("Blind - Bed 3 up", Off);
        Delay(1);
      End;
      PulseCBusLevel(254, 56, "Blind - Bed 3 down", 100%, 0, "0:00:50", 0);
      Bed3BlindMode := 'Open';
    end
    else
    begin
      if (GetLightingState("Blind - Bed 3 down") = On) Then
      Begin
        SetLightingState("Blind - Bed 3 down", Off);
        Delay(1);
      End;
      PulseCBusLevel(254, 56, "Blind - Bed 3 up", 100%, 0, "0:00:50", 0);
      Bed3BlindMode := 'Close';
    end;
end;

once (GetLightingState("Bed 3 btn Blind") = Off) then
begin
      SetLightingState ("Blind - Bed 3 up", Off);
      SetLightingState ("Blind - Bed 3 down", Off);
end;

The two channels are on a changeover relay for electrical interlocking, even though there is a code interlock here.

 

Somfy Motors to Building Management System

Hope this answers everyones questions

Somfy Motors to Building Management Systems

A general overview of all the options of connecting Somfy Motors to C-bus