control fan with Logic

To do anything based on time of day, you need a device that's capable of schedules for a start, so you'll need a PAC, Wiser, or Touchscreen.

Create a schedule that sets a new group, say "Night Time Level" to 30% at 12am, and another schedule that sets "Night Light Level" to 100% at 6am.

Once you have this, use the output unit logic (on the logic tab in the dimmer/relayGUI in Toolkit). Select "Night Light Level" for the logic group, and for the dimmer, select "Min" logic, and for the relay, use "And" logic.

For the relay, set the turn on threshold at, say, 50%.

What this does, is in the dimmer, the actual level applied to the channel is the *minimum* of the logic group and the channel group, so between 12am and 6am when the "Night Light Level" is at 30%, when your switch or PIR turns the group ON, the channel goes to the minimum of 100% and 30% ie 30%.

The "AND" logic in the relay works more or less the same, but because a relay can only be ON or OFF, it's just a logical AND. The turn on threshold gets applied before the logic though, so when "Night Light Level" is at 30% and the turn on threshold is set to 50%, then the channel is OFF, so the channel output is a logical AND of "ON" (from the PIR), and "OFF" from the "Night Light Level + Turn on Threshold", which results in the fan being OFF.

Hope this makes sense.

Nick