how to enable mutiple groups on a button

What is the easiest way to enable a single C-bus button on a switch to control more than one group? For example, how would you program a button to switch on both a fan (wired to a relay output) and a light (again wired to a relay output). Do you need to create a scene, or is there a simple way of using some kind of logic? Again, if the light was wired to a dimmer output, how could you ensure that the fan on the relay output was switched on whenever the dimmer channel was enabled?

 

If you used a single key to control the multiple groups using the block definitions, I presume that if you were using on group from a relay (connected to the fan) and the other group from a dimmer output (connected to the lighting), then the key would only be able to be set up to turn the groups on and off. You would not therefore be able to dim the lights up and down. Is this correct?

Is this also the case if you assigned a single group to both the dimmer output and the relay output?

I wasn't aware that you could define a single group for differnt outputs, but I suppose the issue is again that you couldn't use the switch to both dim the dimmer channel light, and switch the fan connected to the relay. Is this the case?

 

You can still dim.

If you set the turn on value int he relay to say 80%, then the relay channel wont come on until the group is 80% or more, but the dimmer channel will be on from 1% onwards.

So you could dim the light up and down, but it wont turn on the fan until the light gets really bright (80%)

Mick