How much/what electrical danger performing on a covered stage during rain?

snipped-for-privacy@redshark.goodshow.net wrote:


For what it's worth, In Europe, a ground fault protection device *must* trigger at no more than 30 milliamps after no more than 30 milliseconds. There are`also rules about regular testing of fixed installations, & for testing temporary installations before first use.
--

Tciao for Nw!

John.

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John Williamson wrote...

Actually RCDs are available with tripping currents of 10, 30, 100 & 300mA and in time delayed versions. That's only from the MK "Sentry" catalogue - there are probably others available as well.
David
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"David Lee"

** Try reading the whole story.
MK state clearly that ONLY the 30mA models are capable of giving good shock protection.
The 100 mA models are ONLY intended where a 30 mA one cannot be used - presumably because inherent circuit leakage to ground equals or exceeds 30mA.
MK also state the a 300mA model is PURELY intended for equipment and fire protection.
http://www.tlc-direct.co.uk/Technical/Distribution/RCD.htm#Quieries
...... Phil
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From the point of view of UK wiring regs, RCDs used for protection against electrocution must be rated at no more than 30mA (and this is similar in many other countries wiring codes too). RCDs for protection against high earth fault loop impedance and not electrocution should be rated at least 100mA. 300mA and 500mA are common values too.
10mA RCDs as mentioned above are available but are rare. They are used for protection against electrocution in restrictive conductive locations (where someone may not be able to remove themselves from contact with faulty live part due to working in a location which restricts movement, such as maintenance work inside a pipeline). 10mA RCDs are also suitable for single appliances, but generally not suitable for circuits feeding many appliances, particularly Class I IT equipment.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
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"Andrew Gabriel"

** Care to explain you pompous jargon ?
The mysterious phrase " high earth fault loop impedance " don't mean jack shit to anyone.
The use of plain language is always preferred when addressing an audience.
....... Phil
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wrote:

Err that is plain language, the its the minimum impedance a fault to ground can flow through. Jack Shit will almost certainly have to high a resistance to comply with code.
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"Duncan Wood" Phil Allison "Andrew Gabriel"

** It is plan bollocks.

** Worse gobbledegook than the original verbal diarrhoea.

** Is about all you know.
...... Phil
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wrote:

It's the impedance of the entire circuit if you short the phase cable to ground, including the LV transformer & feed cable. So divide your phase voltage by the earth fault impedance & you get the maximum current that can flow. If that's still gobbldegook then you need some basic knowledge about electricity to play. Or use google.
http://wiki.myelectrical.com/index.php?title=LV_Fault_Calculation_Overview

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" William Sommerwanker Utter Shithead "
Piss off - wanker !
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Open heart surgery, defibrillator paddles are 2" in diameter and operate at 2mA.
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Its not "usually" the sound system that creates the hazard its the guitarist who has a groud fault or has snipped off the ground lug from his power plug or is incorrectly using a edison adapter wo creates a hazard condition when his improperly grounded rig meets the right condition and a properly grounded rig the current flows from his source(amp) out his guitar cable into his guitar now all he has to do is touch his strings and a mic stsand of a properly grounded system toallow the current to complete its journey to ground right through his body
"most" sound companies are accutly aware of proper electriacal protocol most musicians are not George
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Exactly! I've worked around computers (not here in the USA) where a ground was not available (a "special" adapter was used to remove the ground... funny how those adapters are sold in stores), and it *hurts* when you touch the chassis. 220V, too. We learned very quickly to shut down the computers before plugging/unplugging devices, to avoid pain.
Even when plugging my laptop into the mains to charge it, I'd get an unpleasant shock if I even touched the ground around the microphone Line Out jack.
Oh, here in the USA, the government really CARES about us! haha
Michael
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In the US, I've seen 2 types of adapters.
One has a 3 pronged outlet with a 2 prong plug and aw ground wire that is intended to be connected to the screw that holds the plate on. Assuming that there is a metal box, and it is grounded (big assumptions). If everything goes as to plan, the 3 pronged outlet should then be fine. The advantage of the wire is that you can use one in each outlet. Some people just cut off the wires and ignore the ground (bad plan).
The other style is the same thing except with a spade attached directly to the plug in such a position that it can be connected directly to the screw to provide a ground and it locks the adapter onto the outlet making it more stable. You can only use one on a duplex outlet.
If used correctly, these are fine tools, but using them to lift the ground is not allowed.

That isn't a situation that you should have to put up with. Typically a laptop floats and isn't directly connected to ground. There is probably something connected to it that isn't wired correctly, or has some other fault. A while back, the RF cable for the cable TV had quite a bit of kick when referenced to a water pipe ground. We have fiber running directly to the side of the house now. It is no longer an issue :-)

They try, but you have to remember that some of "us" are retailers and manufactures may have a different slant on what caring should be. Sometimes they have more pull than you or I.
David

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any mains powered electrical equipment operated in the rain is potentialy lethal unless it is sufficiently protected from water geting in.
it might not hurt if the microphone got wet, but if the amp it is connected to got wet ... fizzle hiss zap
do people still use mic cables much for anything larger than a pub performance ?
Colin =^.^
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Absolutely. This means putting the stage in a fairly well-protected tent (which means lousy acoustics, sorry about that), double-insulating the power system and covering all camlocks and junctions with plastic sheeting. It means careful grounding, GFIs, and it means a power dispatcher who wanders around with a meter checking ground fault currents so he has a good idea when the leakage is getting to the point where a GFI may pop.

It's easy to keep the equipment dry. But keeping the _people_ dry is the hard part.

Sure, thousands and thousands of feet of the stuff. It just works, unlike wireless systems. --scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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HiC wrote:

If its tipping down with rain, would the audience still be there? Might be no need to perform in the first place.
Just a thought...
Chris W
--
The voice of ignorance speaks loud and long,
But the words of the wise are quiet and few.
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For example, you can see the umbrellas in the audience and when you see the shots from behind Bianca - who was the warmup act for Hall & Oates, you can see it's coming down pretty good. Apparently the performance was moved to this covered stage because of the weather.

http://youtube.com/watch?v=JLHZsauQsOY

She's using a wireless, even so, could there still be any other potential hazards to her or others?
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This is why GFI's are often required for any outside power. bk

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It is absolutely essential that all the power circuits have Ground Fault Circuit Interrupter (GFCI) protection, and that these be tested during the initial installation. It's also a good idea to surge protect all the equipment plugged directly into the line. All of the handheld electricals should have a UL double insulation rating.
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"Fred Bloggs"

** Complete insanity !!!!
It is COLOSSALLY DANGEROUS to use a class 2 item after it has become WET !!!
The Bloggs goon is a complete MORON !!
....... Phil
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