Up grade a D20E dimming panel to LED lighting for a GYM

It will all depend on the technical details of the fixtures, particularly the drivers. Are you replacing just the tubes, removing the ballast, or doing the whole fixture. Your best bet is to inquire about the dimming preferences of equipment.

The good news is that there is a strong possibility the D20 will work, maybe with some settings changes. You could replace the D20 with an ELV module if it needs 'electronic' dimming. Or if dimming is needed at all then an R20 module will run almost anything, it's just a switch.

Regardless, call tech support to get help in changing the rack settings. They also have tested a wide range of fixtures so might have the specific info you need.

I would like to replace the whole fixture. And dimming is a requirement.

Then you should consider the dimming type when selecting the fixture! The fact that it is LED really doesn't mean much.

There are many technologies; 2 wire forward phase cut (standard dimming), 2 wire reverse phase cut, 3 wire (line voltage), relay + 0-10, relay + DMX, and Dali. Unison racks can handle them all, Sensor racks can do most of them.