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[Stephen Swaffer]

Since you are using a 20 amp GFCI as your supply I am assuming the 10/3 is a hot/neutral/ground.  As long as there is a GEC at the genny you do have a GEC connection-bonded through the EGC.  However, it has been discussed in other threads that a ground rod is not a bad idea at the stage.  #8 to that screwed to stage would be fine-personally, I would prefer it to be connected to the same piece of aluminum as the quad box probably not a huge deal but for various reasons I think it the best practice.

[frank kayser]

Since you are using a 20 amp GFCI as your supply I am assuming the 10/3 is a hot/neutral/ground.  As long as there is a GEC at the genny you do have a GEC connection-bonded through the EGC.  However, it has been discussed in other threads that a ground rod is not a bad idea at the stage.  #8 to that screwed to stage would be fine-personally, I would prefer it to be connected to the same piece of aluminum as the quad box probably not a huge deal but for various reasons I think it the best practice.

I agree.  I'd use the same bolt and star washer to attach both to the stage at a single point.

[jasonfinnigan]

There is no need to bond to metal quad box to ground on the stage as if it is properly wired it would already be bonded inside the metal box to ground that is coming from the genny (the rod, which your stage is also bonded too).

[Mike Sokol]

I agree.  I'd use the same bolt and star washer to attach both to the stage at a single point.

+1 - I like a piece of #8 stranded bonded to a single point. That gives you the best lightning protection and a great low-impedance path for any fault currents from the stage. 

[David Sturzenbecher]

It would be nice if there were some standard hardware (made by the stage co's) that one could clamp or attach to the stage, and plug into with a piece of 2AWG with green camlocks...


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[Cailen Waddell]

So when I have 8 4x8 platforms in a parking lot, metal legs and frames, wood tops - would you ground every platform individually? 

We ground our stageline sl100 all the time but for smaller stuff, It's difficult....


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[Jonathan Johnson]

Or maybe they figure grounding anything that needs grounding to the distro is my job and they want to make a clear cut boundary between their "system" and the rest of the world, perhaps for liability reasons.

Grounding the stage ends up being kind of a "not my problem" problem.

• It's not the PoCo's problem; their responsibility ends at the meter (or in this case, the temporary power panel they provide).
• It's not the staging provider's problem (they don't do anything electrical).
• It's not the lighting or sound provider's problem (they didn't provide the stage -- and the distros are basically glorified extension cords).
• It's not the promoter's problem (it never is).

But you, now being made aware of the problem, have a social responsibility to ensure that best practices are observed to create an electrically safe environment. For the best liability protection, you don't address the issue yourself (unless you are a licensed electrician); rather, you hire a licensed electrician to do the work and backcharge the promoter. In the future, you include this in contracts and riders.

P.S. -- If there are multiple stage platforms, there should be an electrical bond of some sort between each frame in addition to the bond from the first platform back to the distro/ground rod.  I'd be careful drilling into stage frame members; drilling in the wrong spot could compromise strength. Some kind of clamp would be ideal; the kind of clamp used for grounding to water pipe may be usable -- but you must have a metal-to-metal connection. Paint or other coatings could create a high-resistance or insulating connection.

[jasonfinnigan]

So when I have 8 4x8 platforms in a parking lot, metal legs and frames, wood tops - would you ground every platform individually? 

We ground our stageline sl100 all the time but for smaller stuff, It's difficult....


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Do the legs clamp together? Ours don't.  personally I don't bond the wood stages we use at festivals with metal legs, as the stairs are wood as well so it's kinda a bit useless to bond it to ground. there's not point were could could have current on you from a conductive surface on the stage and then step on the ground to get a nice shock, since wood isn't too conductive (read: anything CAN conduct given the right circumstances, it's about how much resistance there is)

[Cailen Waddell]

Do the legs clamp together? Ours don't personally I don't bond the wood stages we use at festivals with metal legs, as the stairs are wood as well so it's kinda a bit useless to bond it to ground.

Our legs have plastic brackets so the stage sections are not electrically connected.  I feel the same as you - but in the interest of this wider discussion - I thought it an important point to raise....


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[frank kayser]

It would be nice if there were some standard hardware (made by the stage co's) that one could clamp or attach to the stage, and plug into with a piece of 2AWG with green camlocks...

Noting the silence from just about everywhere on the web, it would be nice if the stage companies (especially the all aluminum) would make some mention that their platform should be grounded...


ah, but there' liability as referenced by Jonathan...

Grounding the stage ends up being kind of a "not my problem" problem.

• It's not the PoCo's problem; their responsibility ends at the meter (or in this case, the temporary power panel they provide).
• It's not the staging provider's problem (they don't do anything electrical).
• It's not the lighting or sound provider's problem (they didn't provide the stage -- and the distros are basically glorified extension cords).
• It's not the promoter's problem (it never is).

But you, now being made aware of the problem, have a social responsibility to ensure that best practices are observed to create an electrically safe environment. For the best liability protection, you don't address the issue yourself (unless you are a licensed electrician); rather, you hire a licensed electrician to do the work and backcharge the promoter. In the future, you include this in contracts and riders.

P.S. -- If there are multiple stage platforms, there should be an electrical bond of some sort between each frame in addition to the bond from the first platform back to the distro/ground rod.  I'd be careful drilling into stage frame members; drilling in the wrong spot could compromise strength. Some kind of clamp would be ideal; the kind of clamp used for grounding to water pipe may be usable -- but you must have a metal-to-metal connection. Paint or other coatings could create a high-resistance or insulating connection.

Now you've ruined my good intentions, Jonathan. (just kidding...)
Though getting the stage sections there from the city requires an Act Of God, then the stage sections are not physically attached to each other... let alone an electrician.


Can I, in good conscience, use the stage now without proper grounding, should I just refuse the job, or stand paralyzed Waiting for the Electrician or Someone Like Him.


Would my liability be more acting to avert an electrocution, or ignoring the problem.  I know the answer.  No one can know someone else's mind.


Good deeds never go unpunished.


frank


p.s. Letter going to the city today.  Maybe they just won't supply the platforms any more!  Problem solved!

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