About XLR Connectors:

The XLR connector is an electrical connector design. XLR plugs and sockets are used mostly in professional audio and video cabling applications, often for microphones and other signal processing gear.

The most common is the three-pin XLR3, used almost universally as a balanced audio connector for high quality microphones and connections between outboard equipment and audio mixerst. XLR4 (with four pins) is used for ClearCom and Telex communication headsets and handsets, DC power connections for professional film and video cameras and older versions of AMX analog lighting control. XLR5 is the standard connector for DMX 512 digital lighting control and is also used for dual-element microphones and dual-channel intercom headsets. XLR6 is used for dual channel intercom beltpacks.

Lighting control for entertainment applications is widely connected using five pin XLRs. While only three pins are used to carry the DMX512 signal, the design allows expansion with the remaining two pins considered for use with Remote Device Management (RDM) and Architecture for Control Networks (ACN) and also prevents users from confusing lighting with common XLR3 audio cables. Unfortunately, five pin XLRs still allow the use of lower-grade (non-110 Ohm) microphone cable for transmission of signals. Some manufacturers of DJ lighting and professional lighting are still using three-pin connectors as their standard.

Rechargeable devices exist that use three-pin XLR connectors. These can be found on electric powered mobility wheelchairs and scooters. The connectors carry from 2 to 10 amps at 24 volts.