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[John Strzalkowski]

Quick question. Is there any positive/negative effects of connecting the shield to the ground on the XLR connector?

Is it standard practice to ground the sheild? or should I let the lights do it internally?

Any help would be nice,

Thanks,
John

[Milt Hathaway]

John Strzalkowski wrote on Mon, 07 December 2009 16:18

Quick question. Is there any positive/negative effects of connecting the shield to the ground on the XLR connector? Is it standard practice to ground the sheild? or should I let the lights do it internally?

I have never ever heard of any application that required the connector body to be connected to circuit ground (which is often different from chassis ground for many reasons.)

There are plenty of reasons not to, however, including the desire to keep from interfering with the relationship between chassis ground and circuit ground.

[Todd Black]

the shield should only go to pin 1, and should not contact the shell or ground lug in the connector. (when most of us assemble cables we put heatshrink over the shield to ensure it does not contact the shell). I have seen some expensive damage caused (including blowing up an expensive lighting console) because the shield was grounded. Fault currents take some odd paths.....

[John Strzalkowski]

Thank you both for your posts. Helped me greatly.

For some reason it seems that the some of the pre-fab DMX cable has the shield connected to the lug. It makes me wonder if the manufacturers know the dangers.

Thanks for clearing that up. This question arose after I had already made about 500ft of it without connecting pin 1 to the connector. (would have been pretty painful to re-fab all that cable)

When you heat shrink it, I usually see the heat shrink around all 3 (or 5) pins, is this the way you guys do it? or is it only around the shield.

Thanks again

John

[Todd Black]

I cant speak for others, but when I assemble XLR cables, I install clear heatshrink over the ground conductor (either drain wire, or the strands of the braid which were unbraided, twisted together, and tinned) to insulate it. Then some larger black heatshrink is used to cover the transition from cable jacket to past where this clear starts. The ground is then soldered into pin 1.