The EPANL uses a 0-10V dimming circuit.
There will be a set of purple and gray wires which extend from the driver inside the fixture. This is a 0-10V dimming circuit. You will need to run a low voltage wire (typically 18 gauge) from these wires to a 0-10V dimming switch. You can install the wiring from the dimmer switch to the first fixture, then to next, etc. (in a daisy chain fashion). You do not need to homerun each wire. The dimmer switch will also have an input to switch the 120-277V as well as the low voltage inputs for the 0-10V dimming circuit. This will ensure you can turn the fixture off as it will only dim down to 10%.
In theory, any 0-10V dimmer switch is compatible, but Acuity recommends using the SPODMRD.
Attached is a spec sheet for the SPODMRD dimming switch.