mutually exclusive scenes

I have to set up a facility which will open and close a window, using cbus to control the direction of the motor. There are effectively 2 motors, so I need to provide power to one of them when opening the window, and provide power to the other when closing the window. Ideally, a changeover relay would have perhaps been the best solution, but the system only has conventional relays installed.

Clearly, it is important that only one motor is powered at any time, so I thought that perhaps using scene controls may be the answer. I seem to recall there is a way of making scenes mutually exclusive, so if one scene was powering the motor to open the window, then it would be impossible to provide power in the opposite direction. Can anybody tell me how to create mutually exclusive scenes?

Alternatively, does anybody have any other suggestions as to how I can ensure that at no time will power ever be provided to both motors simultaneously?

Thanks
Neil C

 

What is the relay unit you are using?

If it is a DIN unit, and if you put your motors on channels 1 and 2 of the relay, then you should be able to set up interlocking (in the 'Turn on' tab) for the first 2 channels. This interlocking guarantees mutually exclusive operation of the first 'n' channels.

I'm not sure when it will be released, but if you are patient, we have a special 2 channel 'shutter relay' intended for exactly this sort of work which natively enforces mutually exclusive operation of its 2 relays.

 

In most of our cases, one relay channel for Open, another relay channel for Close. E.e. GA01 is open; GA02 is close.

First of all, we will definitely install a conventional interlock relay set at the outputs. No matter how you program the relays, there will be chances that both relay channels power up together after power failure or local toggles..etc. in case the motors are not that good, the interlock relays would protect it.

porgramming with scene is the easiest choice to me, but you need three keys/scenes for Open, Close, and Stop for a single curtain. Scene is a one off command. It tells the relay to open or close once, but it wouldn't monitor and keep the setting. So, after you press scene 1 (say GA01=ON, GA02=OFF), you can go to other scene whenever you want (e.g. GA01=OFF, GA02=ON). So there is no such Mutual Exclusive issue in Scene. All you need is mutual exclusive channels in relays. While you can have them in the first 2 channels in a relay, there is no other way of doing it. So, the conventional interlock relays shoudl be the easiest, cheapest way of doing it.

The problem of using scene is that people will not press stop after pressing Open or Close, so one channels will always active most of time.