I looked and looked for the answer to this question and found nothing but a lot of unanswered posts like yours. I was able to figure it out after a lot of hours on the internet but I never found it all in one place. So here is my cobbled together How To... I hope it helps.
What I am showing you here is how I did it... the step by step might not be perfect or how someone else has done it; but it works.
This also assumes that you are trying to dim Reef Brite Lumi Lite Pro's. (Non-Pro do not dim)
Step one, create ramp profiles. Click the gear on your dashboard, click the file icon and you will see a list of PF numbers; we need 2 of these, I used 1 and 2. Select PF1and change the name to whatever, I used Lite_RampUp. Next select Type RAMP. Under configuration Ramp Time = how long in minutes you want the ramping to take. Default is 60 minutes. Start and Stop intensity are self explanatory and are represented in percentages of 0-100%. I used Start of 0 and End of 100. <Send it to the Apex>. go back to the list of PF's and select PF2. This will be the opposite of the ramp up we just created. Name it Lite_RampDn and enter Time = 60 Start = 100 End = 0. <Send it to the Apex>.
Step two; you need an open 0-10V control port (There are 2 RJ45's on the Apex Base Unit or you can use a VDM module from Neptune which also has 2 RJ45 plugs). This is where you plug in the male RJ45 that came with your Reef Brite Channel Controller.
Next; you need to configure the 0-10V ports that you just plugged the RJ45 into (lets assume apex base unit v1/v2... 1 RJ45 = 2 control channels). First check your new tiles and look for tiles with the prefix VarSpd... You need to program two of these and it doesn't matter which two; for this exercise we will use the _1 and _2. Move them down to your dashboard and click the gear icon on _1. Change the name and the icon if you wish and select control type "Advanced". This is where we tell the LEDs when to ramp up and down using the Lite_RampUp and Lite_RampDn profiles we built back at Step 1. We will make sunrise start at 7AM and it will take 60 minutes to ramp up from 0-100% intensity. Sunset will begin at 8PM and will take 60 minutes to ramp down from 100-0% intensity. We will accomplish this by entering the following code: (I am leaving the line numbers off for easier copy and paste. This will start on line 1.)
Set OFF
If Time 7:00 to 20:00 Then Lite_RampUp
If Time 20:00 to 2100 Then Lite_RampDn
<Send it to your Apex>.
Go back to your dashboard and click the gear icon for _2. Rename and click the copy icon next to the "send to apex" cloud icon. Copy configuration (whatever you renamed _1) and <Send it to your Apex>.
Now clap the dust off your hands and admire your handy work.
P.S. have a look here before you cable up your Reef Brite Channel Controller to your Lumi Lite Pro's...
I bought a pair of @Reefbrite 72" LumiLite Pro's and the Apex Dual Channel Interface. I programmed everything perfectly on the Apex/VDM/Profile and installed the lights and channel interface per the manufacturer instructions. Here is the pertinent portion: "Simply plug the interface inline...
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