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[g'bye, Dick Rees]

I once did a festival gig down in Annapolis where we had to run a snake and power 60' across a parking lot from the stage to my FOH mix position. So we put down a bunch of Yellow Jacket cable ramps and set orange traffic cones every 10 ft or so. Now this was a black and yellow striped ramp with bright orange cones you probably could have seen from space. But even before the concert began and with nobody else in the parking lot, one lady walked right up to the cable ramps, tripped over a traffic cone, and fell flat on her face. She was walking and talking to her friend and never looked down. Ouch!

Darwin.

[Ray Aberle]

It is interesting to observe how people can trip more readily over cable ramps then they will if you just laid the cable out on the pavement... it's like, "we're doing this for your safety" yet it ends up being more risky? Awkward.

[Mike Sokol]

It is interesting to observe how people can trip more readily over cable ramps then they will if you just laid the cable out on the pavement... it's like, "we're doing this for your safety" yet it ends up being more risky? Awkward.

No matter how hard you try to idiot proof something, they're always making better idiots. 

[Ray Aberle]

No matter how hard you try to idiot proof something, they're always making better idiots. 

Then the AHJ will be all like "that's nice about the cable ramps. Now put up a sign warning people about them. And make sure the sign won't fall over."

Same series of events, generator at CenturyLink Field in Seattle for the Seahawks games. Generator sitting on property until well after the game-- "Blue Thunder" drum group is playing-- and I'm there having to stop people from climbing ON the generator... sheesh. Do I climb on the bumper of your car?!?

[Mike Sokol]

and I'm there having to stop people from climbing ON the generator... sheesh. Do I climb on the bumper of your car?!?

Only the hot chicks are allowed to dance on my subwoofers in front of the stage, but I think that's a universal law or something... 

[Eric Simna]

It is interesting to observe how people can trip more readily over cable ramps then they will if you just laid the cable out on the pavement... it's like, "we're doing this for your safety" yet it ends up being more risky? Awkward.

And senior citizens are the worst when it comes to cable ramps.  I had one little old lady yell at me and say it was "stupid" to use that "bump."  She changed her mind after I explained the bump was better than if she tripped over the cables under that "bump."  I sometimes think they'd be safest if they were camouflaged.

[Stephen Swaffer]

Then the AHJ will be all like "that's nice about the cable ramps. Now put up a sign warning people about them. And make sure the sign won't fall over."

All he warning signs do is tell the AHJ that you know that you have created a hazard-and the hazard is still there.  What are you going to to do to eliminate the hazard??  Actually had an OSHA instructor point out that issue in regards to "Wet Floor" signs.  It really is a losing game.

If you borrow extension cords-even for short runs to a genny make sure you double check the ground prongs.  It seems like they are engineered to have a life expectancy of about 1/10th the power prongs.  Unless the cords are like new and well cared for they will be missing.

I agree we should not fixate on 3 wire/4 wire and it seems like the OP has already ruled out a distro.  I think the important thing for general knowledge is to understand that a 3 wire 220 V circuit is never acceptable for a distro supply; whereas, a 4 wire should be acceptable.  Doesn't matter whether it is dryer/range, resi/commercial/genny.....
 

[Mike Sokol]

If you borrow extension cords-even for short runs to a genny make sure you double check the ground prongs.  It seems like they are engineered to have a life expectancy of about 1/10th the power prongs.  Unless the cords are like new and well cared for they will be missing.

For the OP: Yes, broken off ground prongs on the extension cords are a big No-No and something you can't allow on your stage, no matter what the power source. You may be able to workaround a lot of other things, but that's the most important takeaway from this thread.

[Jonathan Johnson]

If you borrow extension cords-even for short runs to a genny make sure you double check the ground prongs.  It seems like they are engineered to have a life expectancy of about 1/10th the power prongs.  Unless the cords are like new and well cared for they will be missing.

They ARE engineered to have a shorter life expectancy, though I suspect the engineers don't realize it. The ground prongs are constructed similar to a crimp-on terminal. There's a ring the gets crimped onto the wire, then a narrow bridge to the prong, which is made pretty much identical to the crimp ring. The pin breaks at the bridge, which is just barely inside the molding. (If more of the tubular portion of the ground pin was in the molding, it would be stronger.) The power prongs are much thicker and wider where they join their respective crimp rings.

My extension cords are well cared for, and the prongs STILL break off after a couple of years. I think it should be standard practice to just replace the male end of an extension cord with the most heavy-duty plug you can buy as soon as you purchase it. Probably should do the female end, too, since the contacts on the factory molded ends tend to be weak and get loose quickly.

[Guy Holt]

That's Honda EU Inverter series.  Don't try to get by with anything else.  A "generator" is not a Honda.  Even the non-inverter Hondas won't do.

While the insistence that electrical cords have their ground pins in tact is important, in the context of power generated by Honda EU series generators, it is rather pointless. That is because the Honda EU generators have Floating Neutrals (no bond between the Equipment Grounding Conductor (EGC) and Neutral) and so fault currents will not go to the EGC as they are meant to.  In this context, any discussion of ground pins and the EGC as a low impedance path back to the power source to activate over-current protection is creating a false sense of security.

For the same reason, the test buttons of GFCIs create a false sense of security when they are used on the EU series generators.  Absent a Neutral to EGC bond, GFCIs will not operate on the Honda EU series generators.  A GFCI will only operate reliably if one side of the generator winding is grounded to the generator frame and EGC because otherwise fault current has no path back to the winding to complete the circuit. Only when Neutral is bonded to the EGC, will current go to the EGC to complete the circuit when there is a current leak. In other words, a complete circuit is required to create an imbalance and cause the GFCI to trip.

In this context, GFCI test circuits are misleading when they are used on Floating Neutral generators because the test button draws power from the Hot through its’ Current Transformer (CT) and back through the CT again to the Neutral via a Current Limiting Resister. The discrepancy caused by the Current Limiting Resister in the test circuit (illustrated above) will initiate the GFCI to trip even though there is in fact no Ground Fault Circuit for Fault Current to go to if there were a Fault. The false positive generated by GFCI test circuits on ungrounded Floating Neutral generators does nothing to eliminate faulty equipment and only creates a false sense of security.

These issues related to ground fault protection with Floating Neutral generators like the Honda EU series are well documented by The Construction Safety Association of Ontario (CSAO) in a report on a series of tests they conducted that uncovered significant problems in using GFCIs on portable generators. While the CSAO conducted their tests to determine the effectiveness of GFCIs used on portable generators in typical construction scenarios, their findings are equally applicable to motion picture and event staging production applications (for a more in depth discussion of the problem, how to correct it, and a link to the CSAO’a complete report use this link: http://www.screenlightandgrip.com/html/emailnewsletter_generators.html#anchorElectrical%20Hazard%20Protection)

In the OP's situation, I would much prefer to use the house power, even with the potential trip hazard, because I am assured that a EGC and Neutral bond at the main service panel and an intact EGC will cause over current protective devices and GFCIs to operate reliably.

Guy Holt, Gaffer
ScreenLight & Grip
[email protected]

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