DMX cable wiring - 2 universes

[Steve Vanciel]

Originally Posted by pilchards

So controller A can then share controller B's ground? Controller A is a Chauvet Stage Design 50;
Controller B is a JB Scan Master SM1612.

In theory, is OK ... always the posibility of a particular device not being well engineered to start with and having/causing issues.

I'd have loved to do that, but space is limited!

A second panel XLR should not take up more that a few cm of space.

Is it best to keep the amount of connectors to a minimum? like rather have one 10m cable instead of two 5m cables

Connectors introduce a variable that can be a failure point. Again, in theory, a well built and cared for connector should only add a minor amount of additional impedance to the line that will not effect performance. Yet I would personally try to avoid using ten 10 foot cables in place of a single 100 ft cable.

In regard to paralleling data (or audio) with a power cable, best to avoid if possible. Again, theory tells us that a twisted pair line will reject interference and a twisted pair power cable will not produce an significant electromagnectic field. But, when we get into real world applications, conditions are not always ideal and strange things can occur. Audio oftens blames their hum issues on Lighting when the real problem is incorrect or faulty grounding connections in the audio cables or equipment. Probably why Mike likes metal conduit.

SteveV
Orlando, FL

[pilchards]

Originally Posted by Steve Vanciel

A second panel XLR should not take up more that a few cm of space.

I should take a picture - hehe

Connectors introduce a variable that can be a failure point. ... Yet I would personally try to avoid using ten 10 foot cables in place of a single 100 ft cable.

In regard to paralleling data (or audio) with a power cable, best to avoid if possible. Again, theory tells us that a twisted ... Probably why Mike likes metal conduit.

Thanks Steve - that's what my gut feeling was!

Until our electrics are fixed, there will always be a hum with a dimmer on 3phase - shared earth. Although, with my limited "lay" knowledge of 3phase and single-phase wiring, will a separate earth fix the hum?
Each phase is for lighting, media and sound; and then those 3 phases are bundled into a 3phase socket

Cant wait till the new earth is connected - then I can connect the dimmer without worry!

[pilchards]

Originally Posted by waynehoskins

If it were me, I'd go for a multiple-output opto-splitter at a central location (control booth, dimmer rack) like an ETC Response Splitter, and then make home runs to each position. Interference from power shouldn't be an issue to worry much about, I don't think.

Our stage is temporary, so I'd rather use splitters wherever they are needed. Also a rack mount splitter and extra cable goes waaaaay above my [already depleted] official budget

[pilchards]

Originally Posted by Steve Vanciel

A second panel XLR should not take up more that a few cm of space.

so while i waited for the forum to come back online, i took a good look at how much space i have. i have cut an extra hole in the plate by the stage for a second socket. i just need to locate a box for the other side.

think i'd prefer making it simple for the person after me - 2x 5pin on both ends!