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Tie-in advice. Recources.


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Hi everybody,

 

I'll be gaffing a feature next month and yes a low budget. We don't get a real genny, a couple Honda 3000's is all, not a huge deal, mostly smaller fixtures and no need for 240. I expect to have to tie-in at several of the locations. Mostly my experiance in this is for simply adding additional breakers to the box and wiring for install. Can anyone point me in the direction of some good recources, books, websites, etc... that can provide some more film specific info. Harry Box's book is wonderful, but does not go into it enough.

 

For instance, I'd like to build a box that will tie in and give me a couple 30 amp 120 circuits. Is that not feasible? Worst case I'll just install a couple breakers (if there is room) however I'd like to have my own distro box with its own breakers.

 

What do you think? Thanks a lot!

 

Phil Gerke (Who clearly does not spell check)

Edited by Phil Gerke
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Hey Phil,

 

If you aren't familiar with doing tie is I would stay away from doing so until someone teaches you.

 

Can you get someone on your job that already has that experience or is a licensed electrician and could easily figure it out?

 

Unless you can do that I would stick to installing a few breakers to give you what you need. Installing breakers has a level of safety to it that doing tie in does not have.

 

Best

 

Tim

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If you're not comfortable doing a tie-in, I would speak with members of the production and mention that doing a tie-in is not an option, for safety purposes. Tie-ins are merely used for saving money on a small budget production and they are not worth the risk of your own personal safety and the surrounding crew. Unless you can have a qualified electrician modify a stage box for you and make the proper connections in the panel, I would STRONGLY advise against trying to learn how to tie-in via this forum or any other website.

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We've had this asked here before - it really should go in a FAQ or something.

 

The consensus has always been that if you have to ask how to do it on an internet forum, you should not be doing it. Frankly, if you have to ask specifically because you have a job, before you've learned how to do it on other jobs, you should not be doing it.

 

Nobody who posts on this forum will be willing to be responsible for telling you how to do it. Sorry.

 

P

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Even adding breakers into an existing panel isn't a "good" idea if you aren't quite certain of what you are doing. Can you tell the difference between single phase, three phase delta and three phase wye? Do you make certain that you have the phases in the panel reasonably balanced? No current or very little current on the neutral? How do you bring the new circuits out of the panel? Through a knockout in the box or hanging out the front? If the panel cover is left off, you have created a hazzard for everyone on the set.

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If you're not comfortable doing a tie-in, I would speak with members of the production and mention that doing a tie-in is not an option, for safety purposes. Tie-ins are merely used for saving money on a small budget production and they are not worth the risk of your own personal safety and the surrounding crew. Unless you can have a qualified electrician modify a stage box for you and make the proper connections in the panel, I would STRONGLY advise against trying to learn how to tie-in via this forum or any other website.

 

BIG PLUS ONE ON THIS!!!

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I'll add what I say every time this question comes up. In most, if not all, states, it's illegal to do a tie-in if

you're not a licensed electrician. Sure, lots of people do it but you don't hear about all the stuff that happens

either.

 

Even if you do everything correctly, you are liable if that house or somebody or both get fried.

 

I know it's tough to get work sometimes but it's kind of like saving money on life jackets. The company tells you that

it can't afford to get enough life jackets to meet the legal requirements of the lifeboats. Well, when the lawsuits come

in, and you were in charge of the lifeboats and you didn't follow the law, don't expect the same company that's

squeezing you now to leap to your defense.

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Thanks so much for the feedback. When tie-in was first uttered I should have put my foot down, but I did not. And popping in some breakers is a far cry from tying in and as said before still not a great idea. To be honest I am a little embarrassed, I appreciate the concern and matter of fact-ness in your responses. There is a reason that info like this is not readily available (and illegal) it keeps people from getting electrocuted. This is not a good idea no matter how I look at it. At the risk of losing some of the producers confidence in me, its just not right to be screwing around with this. I was on the fence before, needed to get chewed out a little:)

 

We will be house power and putputs only. I've done more with less. The tech scout is in a couple weeks, they alloted a day, but I will push for 2.

 

Just curious, how often is this really done? It seems foolish, if a production cannot spring for a genny then they sure as hell can't risk an "accident" of any type right?

 

Thanks a lot guys!

 

Phil

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A guy here in town had a fireball ignite from (presumably) dust particles settling on the hot as he was tieing in. This is someone who is a licensed electrician, and who does many many tieins. He lost his vision for (luckily only) 20 hours or so. Doesnt seem worth the risk to me.

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A guy here in town had a fireball ignite from (presumably) dust particles settling on the hot as he was tieing in. This is someone who is a licensed electrician, and who does many many tieins. He lost his vision for (luckily only) 20 hours or so. Doesnt seem worth the risk to me.

 

Nothing personal Mike but that story is far from the truth. Dust particles could in no way create a fireball doing a tie in unlesss accompanied by trapped inflamable gas and then it's the gas not the dust that would explode. Making a mistake can, but not dusk particles. Sounds like the guy made a mistake.

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Tie-ins are merely used for saving money on a small budget production

 

Just for the clarification, this is not true. I have worked on all sizes of jobs and there are other factors that may come into play when deciding if a tie in is feasible aside for the technical reasons.

 

Best

 

Tim

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This link you refer to is for things such as silos and factories where high concentrations of certain combustible materials exist. No tie in in a normal situation would cause such an explosion. Please can we stop confusing knowledge with internet searches.

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Particles of the right material can certainly make a fireball, its just that conditions have to be right. A common way to make a fireball for movie stuff is using powdered naptheline in such a way that the ball of dust (of naptheline) ignites, creating a fire ball.

 

Disneyland's Fantasmic show used powdered creamer to produce fireballs. You can also take a lit candle and gently dust flour over the candle and get a nice little fireball, or do the same with sawdust.

 

That said, the only way the above story could have happened was if there was a nice concentrated cloud of particles in the air and he created a spark while doing the tie-in.

 

It really doesn't take major industrial quantities of dust to create a ball of fire.

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I would make a call ASAP and tell them that, in researching, you have concluded that you don't have the proper training or licensing to do a tie in. if they want it bad enough, they can hire a proper licensed electrician. That should be fine to any producer with a brain and will not make you look bad.

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I would make a call ASAP and tell them that, in researching, you have concluded that you don't have the proper training or licensing to do a tie in. if they want it bad enough, they can hire a proper licensed electrician. That should be fine to any producer with a brain and will not make you look bad.

 

Thanks for that! Meeting this week I am pretty sure, should not be an issue really. Besides once I mention the risk of fireball nobody will want to OK that:)

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A guy here in town had a fireball ignite from (presumably) dust particles settling on the hot as he was tieing in. This is someone who is a licensed electrician, and who does many many tieins. He lost his vision for (luckily only) 20 hours or so. Doesnt seem worth the risk to me.

Dust particles settling on the hot isn't going to do this unless there is a thick enough cloud of conductive dust particles to allow the hot to arc with the ground or neutral. Not bloody likely. A more reasonable explanation would be that the said electrician accidentally shorted a hot to ground causing a large spark that would melt metal and do other fun things that could include igniting flammable dust or vapors. Most likely just the spark by itself was enough of a "Fireball" that by the time the story got to us it required some other explanation for the exaggerated amount of flame.

 

I once accidentally shorted a hot to ground in a box. Do enough tie-ins hot in questionable boxes and it will happen to you too. I fortunately didn't loose my vision or any of those other things you hear circulate in the various film set horror stories. There was a big fu**ing spark, a bang, and it melted a good deal of metal. If there is a main breaker it will trip, unfortunately I have seen far too many boxes with no main breaker that were obviously no where near being up to code. The fact that anyone allowed them hook up to the utility in the first place often astonishes me. Moral of the story is that if a box is questionable walk away. In this particular case the box was horribly designed with very little room between the hots and grounded metal and the bus bars were basically wired directly to the transformer. It was definitely questionable but often on set we fail to use our best judgment in an attempt to get things done. This is why you shouldn't be messing around with electricity when there is any question whatsoever as to the safety of the situation. I learned a lot from that experience and treat tie-ins with a lot more respect than I did before. I knew what I was doing, but that alone isn't enough to keep poop from happening.

 

Even when you think a box is safe if you know what you are doing you should be taking proper safety measures and using the right tools. Things like safety glasses, insulated screwdrivers and a voltage tick are handy. Things like tricos are illegal and are rarely used in a safe fashion and as such should be avoided. Doing a tie-in because the production doesn't want to rent a generator is a bad idea. Doing tie-ins hot is a bad idea. Doing tie-ins when you don't know what you are doing even if you think you know what you are doing is a bad idea. Tie-ins in general are usually a bad idea. There are times when they are the right tool for the job, but those times are few and far between.

 

~Jess

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Okay all you backyard scientists. Thanks for yet more supposition. Consider that in what has become the topic, this imaginary fireball scenario, such an explosion is just that, an explosion. Not only would you be blinded but burnt, including the possibility of your lungs, hair, clothing, etc. Please spare this thread with anymore ridiculous talk about some sort of particle explosion with tie ins. It does not happen. Particles do NOT settle on a hot lead, then explode. THis story is utter fantasy!!! Have any of you done an actual tie in? I spent a career doing such. Rule number one that any idiot would know, no tie-in is done under load. Rather you secure your pigtails with sash to the box. They are not connected to anything at this point. You attach your connections. No load and there is no spark. End of story. Please whoever started this tread, know that tie ins are dangerous if you don't know what you are doing. You don't. Don't do it. You can kill yourself, and hurt others in the process. Have a licensed electrician do anything that involves opening an electrical box.

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Its not backyard science, its me talking from spending time working in pyrotechnics, and we regularly used fine particle clouds to create a fireball, none of these are really explosions, the burning is pretty slow, not rapid or confined.

 

But, as I said in the previous post, the scenario is ridiculous, the only conditions this fire could have happened in would be a large spark created from doing the tie-in wrong.

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A guy here in town had a fireball ignite from (presumably) dust particles settling on the hot as he was tieing in. This is someone who is a licensed electrician, and who does many many tieins. He lost his vision for (luckily only) 20 hours or so. Doesnt seem worth the risk to me.

 

My comment, the guy either shorted adjacent phases with his tie-in cable or shorted a phase to ground (the enclosure, etc.) . He "flashed" himself, the arc which resulted is rich in UV wavelenghts, gave him a painful but short lived burn on his corneas, making seeing difficult. Welders call this "Sand in the eyes", it clears up in a day or so, depending on the severity. If the guy had been wearing any type of ANSI approved safety glasses, the lenses (even clear ones) would have filtered out most of the UV. Another example where proper protective equipment is essential.

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The dust theory is definitely bogus. The required density of dust in the air is so high that if there was that much just in front of the box, you'd fan it away so you could see what you were doing. If that density existed in a much larger space, like the whole room, we would have heard about it on the evening news, and the guy would be dead. The particles have to be close enough to each other that one burning sets fire to its neighbors.

 

So, if anything about that story is real, it's that somebody shorted a hot to the box, or a hot to a different leg. Depending on the size of the service, you can get a goodly flash in an industrial or commercial location. Most residential locations you'll blow the positect ahead of the POCO's transformer and get a moderate flash/bang.

 

I used to start by putting gaffer's tape on the inner surfaces of the box to make it safer. I still have somewhere my set of battery jumper cable to mole pin females. We used to do tie-ins all the time. It was routine on low budget pictures 30+ years ago.

 

 

 

-- J.S.

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Just for the clarification, this is not true. I have worked on all sizes of jobs and there are other factors that may come into play when deciding if a tie in is feasible aside for the technical reasons.

 

Best

 

Tim

 

 

I understand there are other reasons for doing "safe" tie-ins, I was merely justifying the excuse for doing one on Phil Gerke's project he was speaking of.

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