davisju1;675260 wrote: I don't thank the base unit has a rs232 port that the ai led cable needs.
	The vdm adds that and 4 more 1-10v ports
	 
	The Variable Speed/Dimming module (shown above) allows for the control of the Aqua Illuminations LED lighting systems as well as adding an additional 4 0-10V variable speed ports.:
	 
	•Independent control of the white and blue Aqua Illumination LEDs.
	•Simulate Sunrise/Sunset, Lunar Cycle, Clouds, and Lightning with the Aqua Illumination LEDs.
	•Adds 4 independent 0-10V variable speed ports to the Apex system.
	•Plug and Play. Automatically recognized when installed into the system.
	•Pumps can be dynamically added/removed from the system.
	•Two AquaBus connectors for flexible expansion via AquaBus.
	•Comes with 3' AquaBus cable.
	•Fully upgradeable.
	•Led Status indicator.
	•Compatible with Apex and Apex Lite systems.