The primary connector specified in ESTA DMX512A standards https://tsp.esta.org/tsp/documents/docs/ANSI-ESTA_E1-11_2008R2018.pdf is a 5-pin XLR connector. Clause 7 allows for a 8-position modular connector. There are a lot of deviations.
The diagram is a portion of Barbizon Lighting Things You Should Know about DMX, Art-Net, Streaming ACN, and RDM. https://www.barbizon.com/literature/
3 pin XLR connectors are primarily for audio use. Audio wiring is
Pin 1 Ground
Pin 2 Positive (+) audio not DC
Pin 3 Negative (-) audio not DC
Martin used 3 pin XLR for its initial series of lighting using DMX BUT the 3 pin DMX wiring is the same as audio !
Pin 1 Ground
Pin 2 Data +
Pin 3 Data –
Modern budget lighting uses 3 pin XLR which is not the professional standard:
Pin 1 Ground
Pin 2 Data –
Pin 3 Data +
Big Clive DMX Tester is described at http://www.bigclive.com/dmxtest.htm .
The Unit Load of an RS485 node is 1mA https://e2e.ti.com/blogs_/b/analogwire/archive/2016/03/08/rs-485-basics-how-to-calculate-unit-loads-and-the-maximum-number-of-nodes-on-your-network . The standard allows two 120 ohm termination resistors. Use high intensity low current LED’s to allow you to determine different DMX Statis, of a bicolout LED for simplicity.
Page updated 30 January 2021
DMX-Ethernet Adaptor cable
, http://nebula.wsimg.com/0c47e1771b420ed8da58cec68b0d3cc9?AccessKeyId=E9F99C3F22E876201E3C&disposition=0&alloworigin=1
You can also download an extract from the EKO dimmer user manual, with details of the ANSI E1.11 standard wiring for DMX using both XLR5 and RJ45 connectors from the LSC website https://s3-ap-southeast-2.amazonaws.com/downloads.lsccontrol/HelpCentre/XLR%2B5%2B%26%2BRJ45%2BPin%2BOuts%2Bfor%2BDMX%2Bv%2B1%2B2013%2B01.pdf
Updated 4 February 2021