Are 4-way power-boards dangerous?

[Boggy]

I am rigging a small show (30 lights) in a theatre this weekend and was told by the house technician that no power boards are to be used anywhere in the lighting rig because they are dangerous. In the past I have occasionally used 4-way power-boards to connect 4 x par 56 together and asked what was dangerous about this? His reply was that he did not know why it was dangerous but that it was a standard industry practice to ban them and then went on to name several theatres that have such a ban.

In a bid to find out more, I have two questions:
1) Are power-boards banned in any of the theatres where you work?
2) Why are they considered dangerous?

Hopefully this will help me to work out where I should use them or whether I should bin them all.

[Andy Ciddor]

(1) in many places powerboards are actually specified as a preferred option to the use of piggy-back plugs, although nobody has ever been able to satisfactorily explain why.

(2) I suspect that it comes from people who don't understand the current limiting function of fuses and circuit breakers and who therefore think that a powerboard (or piggy-back plug) would enable you to overload the circuit by plugging in more than one device. It's more than a little similar to believing that black cats cause accidents to happen. (although my sister does have a particularly evil black cat).
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Andy Ciddor

[David Ashton]

And in other places double adaptors are banned because they are illegal and dangerous, it is just a case of which urban myth is in vogue at the time, the best response is,"well that's interesting, can you show me the relevent document?"
Strangely, it's never available.

[GL]

...and duck, in case aggressive (verbal) defense presents itself
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"No matter what age we are, some have never quite left the schoolyard"

[hdmcc]

I have powerboards mounted on my pin-spot bars, and untill someone gives me a better way of plugging 7 small lights on a bar into one plug im sure not gonna stop!

[djrappa]

Given a power board has a little breaker in it how is it more dangerous than a piggy back??

Crazy!

Funnily enough I work for a company where all piggy back plugs are banned because they are illegal! Well except in one property because they are "allowed in theatres only."

Gotta love Qld right Andy?
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Cheers
Clint Dulieu
vrtp

[Andy Ciddor]

[phild]

I think double adaptors went out of favour (in professional applications) because the internal construction of the pins (sockets actually) allowed them to seperate and not make good contact.
Nothing wrong with power boards, provided they comply electrically, are in good order and tagged by a licensed person.
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Never play leap frog with a unicorn

[Andy Ciddor]

As I recall it, we generally stopped using double-adaptors when the piggy-back plug became available in a non-shattering plastic. At that point most sub-2kW luminaires were supplied or fitted with a piggy-back plug and we could stop the really boring and time-consuming process of taping over every double-adaptor with PVC tape to make sure the damned things didn't come undone during the show.

<old fart reminiscence> When I started at GTV9 (1974-ish) in our OB kit we had two huge wooden ammo-boxes (later called road cases) filled with double-adaptors (in rings of 10), roughly 300 per box. Our major source of equipment failures during OBs was double-adapters that hadn't been adequately taped up to prevent the plugs coming loose. We couldn't get away from their use fast enough.</old fart reminiscence>
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Andy Ciddor

[Don Allen]

Commenting on the practice at University of Western Australia, there is no laws covering double adaptors or power boards.

There is a university ruling that double adaptors should not be used as they do not have any overload protection and the plugs can easily fall out of the angled variety.

Individually switched power boards are preferred as they have an overload protection and the plugs can be inserted and removed in a no load condition. The unswitched ones can be used but it is recommended to switch the power board off when inserting or removing plugs.

When you consider the low cost of power boards, these circuit breakers are not very good quality, however there is very few instances of any failures and it is recommended to bin the powerboards if any problems occur.
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Lighting Designer and manufacturer of Theatre Electronics

[Andy Ciddor]

Boggy.
If you want a summary answer to your original question.
The combined professional lighting experience of the people who've contributed to this discussion would amount to more than 150 years, and none of them know of any technical or safely issue with using power-boards, nor do any of us know of any regulation that forbids their use.
Some theatres may indeed have banned them, but some theatres also ban whistling in the dressing rooms and others actually paint their green rooms green. This is proof of nothing at all.
So long as your power-boards are in good condition and have been recently tested and tagged and are visually inspected immediately before you use them, then you are putting yourself in the way of no unusual harm.
If the house technician continues to make these claims, then please give them my email address and mobile number, and tell them to give me a call. It should be fun! We might even bring Allthingstheatre in on a conference call and make a party of it
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Andy Ciddor

[GL]

Woolies sell them in their electrical section beside the batteries and light bulbs, Bunnings have boxes full of them on the shelf and home theatre outlets have some beauties that can be bought for $300. Computer shops sell them with IEC plugs on the end (for PSU's).

Its amazing what urban myth, Chinese whispers and "sounding knowledgeable" can do.
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"No matter what age we are, some have never quite left the schoolyard"

[djrappa]

Yeah the term illegal really gets me going.
I often ask "are the police going to come and arrest me if I plug in this piggyback?"

It's one thing to have a venue policy, like our company does, but I can't stand it when the justification is "they are illegal."

It's like venues that tell you that you must have a license to use their scissorlift. What license? No such license exists, what, an 11m or over Boom lift ticket which covers nothing on the operation of scissor lifts??
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Cheers
Clint Dulieu
vrtp

[phild]

[djrappa]

Nope, that's a 'Trained Operator Card,' I have one myself. It shows you have been trained and most venues take that as your 'license' but it's not actually a high risk license as issued by workcover.

I know that's getting picky, but that's what we're talking about here. The yellow card shows you to be a 'competant person' (well actually it shows you have a yellow card, you could be completely incompetant which is why that term annoys me), but not a licensed operator.

Very much the same as our little powerlock debate here.
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Cheers
Clint Dulieu
vrtp