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12 hours ago, David Peterson said:

2) amps and voltages (& KHz too) varies around the world (for the average household), which may impact your calculations. 
(for instance, most homes in the U.S. are wired with 15-amp 120-volt 60KHz outputs, while here in NZ they'd be 10A 230V 50KHz outlets)

Not to be a stickler, but hertz (Hz), not kilohertz (kHz). If mains was several tens of kilohertz:

- Transformers would be a lot smaller, which would be good

- Losses in distribution would be appalling due to radiative effects. The wavelength of a 60KHz sine wave is about 5000m. Even a 1250m wire would be a quarter-wave antenna at that frequency! The power grid would radiate all the energy away as radio waves!

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In my experience (I still work as a set electric for the majority of my real income) the dividing line occurs when a show or commercial is under union jurisdiction, where you need an electrician to ha

Most of my work falls into this area (running off of household circuits), so my gaffer (if I have one) is often making the call on who to hire.  I would say whenever possible, I want the most exp

That looks the same exact product that is in the kay lites link. Edit: ** It is the same product, Manufactured by AC Power  Kaylites' description: Manufacturer AC POWER Guardian's Description

On 12/26/2020 at 5:44 PM, Phil Rhodes said:

I don't know what the rules are here, but I suspect the rules there could do with a bit of an updating. I'm not sure they'd make that much sense even then. ...

Clearly Article 530 hasn’t been updated in a while.  In fact, there is a proposed update making its way through the approval process that will be part of the 2023 edition of the NEC. The intent of Section 530.1 then as now is to distinguish between professional and amateur productions and align Article 530 with Occupational Safety and Health Administration (OSHA) CFR Regulations. After all what distinguishes professionals from amateurs is that professionals get paid. Paid by whom? By their employer.

According to OSHA regulations the employer is responsible for worker safety and providing safety training, which is why it is the studios that fund the Safety Pass Program and why producers pay $1 into my local’s training fund for every day I work under a union contract.  Since it is not practical for producers to provide safety training for each project, they meet this OSHA and NEC requirement by funding such training by the unions.

The NEC and OSHA definitions of a qualified person differ slightly.  OSHA regulations contain a bit more criteria for qualified people. OSHA CFR Regulation 1910 defines a “qualified person” as “one with a recognized degree or professional certificate and extensive knowledge and experience in the subject field who is capable of design, analysis, evaluation, and specifications in the subject work, project, 
or product.” OSHA CFR Regulation 1926 defines it as “one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated his ability to solve or resolve problems relating to the subject matter, the work, or the project.”


These two definitions differ in that, for general industry purposes, OSHA defines the term as someone who has both a certification and industry experience. The construction regulation contains a bit more criteria for qualified people, including a recognized degree, certificate or professional standing, or who, by extensive knowledge, training and experience, has successfully demonstrated related abilities. The key difference is “demonstrated abilities” related to the project or work. These definitions provide the basis for the more specific definitions of qualified people contained in the NEC and NFPA 70E.

Since workers can be qualified in one area and unqualified for another, in both regulations it is the responsibility of the employer to assign qualified people to perform tasks and operations requiring specific knowledge and skill sets. Even though the employer is ultimately responsible and therefore liable in the event of an accident, employees have a responsibility to know the limits of their qualifications and to admit when they are not qualified to perform a particular task or function. Which makes it necessary for a qualified person to not only have experience, knowledge, skills, and safety training, but also have an understanding of the limits of their own qualifications.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting rentals and sales in Boston

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Guess it depends on the Insurance company.

Only time I was involved with a damage claim, the Insurance paid the claim. The so called set spark was clearly not trained.


I know of hundreds of shoots where there was no set spark and I definitely now they had not received any training but they still had insurance.

Whether a claim would be denied because of that lack of training I do not know as no accidents occurred. 


On the Grippage side I do know that insurance claims were paid on accidents involving Manlifts that happened with operators that had no business being in one. 

No life lost but serious damage to the machines.





 

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On 12/28/2020 at 5:07 PM, Guy Holt said:

After all what distinguishes professionals from amateurs is that professionals get paid.

This sort of thing always makes me suspicious.

The electrical safety hazards facing any person using a particular piece of equipment are identical regardless of whether they're being paid. When people start making exceptions for amateurs, it starts looking like job protectionism and nothing else.

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On 1/6/2021 at 5:17 AM, Phil Rhodes said:

The electrical safety hazards facing any person using a particular piece of equipment are identical regardless of whether they're being paid.

While that is true, paid professionals are more likely to use equipment that warrants safety training than do unpaid amateurs.  NEC Article 520 makes a similar distinction between what is and is not safe for an amateur to use – just in a different way.  Section 520.53(P) permits an untrained person to use only listed plug and cord connected distribution systems of less than 150A.  The operative words being “listed“ and “plug and cord connected.”  A listed plug and cord connected system is a turnkey system whose components are compatible by design, equipped with over current protection sized to connected conductors, and tested to a UL standard. Where there are no exposed live parts and connections are designed to make the Equipment Grounding Conductor first and break it last, listed plug and cord connected systems are extremely safe and almost dummy proof and therefore suitable for unpaid amateurs.  Professional productions that pay their employees are more likely to use such things as feeder taps, single-conductor (CamLok) feeders that can be connected in the wrong order, and over-size breakers by 400%, and so require the services of a trained qualified person.

The Code article pertaining to motion picture studios, NEC Article 530, does not make an exception for listed plug and cord connected systems of less than 150A, but instead draws the line at whether the production is using a professional format or not (Section 530.1 Scope.) Productions using a professional format are more likely to pay employees and use such things as feeder taps, single-conductor (CamLok) feeders that can be connected in the wrong order, and over-size breakers by 400%, and so require the services of a trained qualified person.  Productions using amateur formats are more likely not to pay their crew and use only listed plug and cord connected equipment (a listed extension cord plugged into a listed wall receptacle backed up by listed overcurrent protection.) Since listed plug and cord connected systems are extremely safe and almost dummy proof, they are suitable for unpaid amateurs.

The bottom line is that if you pay someone to plug-in a light, you enter into an employer/employee relationship with that individual. According to the U.S. Occupational Safety and Health Administration (OSHA) you are therefore responsible for their safety and for providing the safety training required by NEC Article 530.  If you are not prepared to provide that training to your crew, your best recourse is to hire a union crew and contribute to the union's training fund.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting rentals and sales in Boston

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On 1/6/2021 at 5:17 AM, Phil Rhodes said:

... When people start making exceptions for amateurs, it starts looking like job protectionism and nothing else.

I agree that job protection is written into the Code, but not the type you think.  NEC Section 530.6 is, to my mind, one of the most important code articles because it creates our job. Without that single article, what we do would likely be the jurisdiction of some International Brotherhood of Electrical Workers (IBEW) Local and require a state license. But, unfortunately, the NEC is not the final word on this issue. Despite its authoritative position and national title, NEC standards are merely a template local government uses to create and enforce their own electric code. Since the NEC provides the minimum requirements for electrical safety it is fairly common for jurisdictions to have local codes or amendments that modify or supplement the minimum rules in the NEC.  These are generally of a nature that makes the rules more restrictive and are usually necessary due to unique or adverse conditions within a particular jurisdiction.

For example, even though Article 530’s definition of a “Qualified Person” does not require a state license, the Massachusetts Board of State Examiners did not adopt it without change. The Examiners, according to the state website “assist local wiring inspectors in mediating code disputes between licensees and wiring Inspectors.“ In a code dispute in 2003, the Examiners added their own requirement, based upon Massachusetts General Laws, that Qualified Persons must operate under the supervision of a licensed electrician.

The history of how we got here is worth exploring in detail because it is indicative of the significance of the Code to local authorities and goes something like this: In 1948, in Maria v. State Examiners, (362.Mass.551,552-555 (1974)) the Board of Examiners petitioned the Attorney General of Massachusetts to rule whether the wires and apparatus used in television installations (CamLok and Bates connections) constituted the use of “electricity for light, heat, or power purposes”, which under Massachusetts General Law requires a license. The Attorney General ruled that it did not require a license. In doing so, he affirmed the role of a Qualified Person as envisioned by the Code.

Fifty-five years later, a Boston Inspector of Wires cited a production company for a Code violation because their crew were connecting and disconnecting CamLok and Bates style equipment without having a company license. The production company appealed the violation to the Board of State Examiners. Citing Massachusetts General Laws Chapter 141 section 8, the Examiners ruled in a Private Letter Ruling, dated July 31, 2003, in favor of the production company over the Inspector with the caveat that “the company regularly employs electricians ...[and] such work is required to be supervised by a person licensed under this Chapter” (the underscore is mine). And, in the next paragraph, citing Massachusetts General Laws Chapter 143 section 3-L, the Examiners asserted their right, as a “matter of consumer protection”, to inspect all electrical wiring and equipment used in filming motion pictures. Including, portable and vehicle-mounted generators and portable electrical distribution systems; additions or alterations to premises wiring systems, permanent electrical infrastructure, or other fixed wiring systems regardless if it will be dismantled, abandoned, or removed at the conclusion of filming.

Where it requires a license in the state of Massachusetts to pull a permit and schedule an inspection, in their ruling the Examiners effectively subjugated Qualified Persons to licensed electricians even though the Attorney General of Massachusetts had previously affirmed the role of a Qualified Person as envisioned by the Code. So, despite its authoritative position and national title, NEC standards are merely a template that local governments use to create and enforce their own electric code.

So where does that leave you? Having to navigate a patchwork of code permutations across the country. Given the variety of code interpretations, it is important to always check with the local Authority Having Jurisdiction (AHJ) for regional differences from the national code. Depending on where the work is taking place the AHJ may be the local city electrical inspector, the fire marshal (also known as a Film Safety Officer), or the studio’s safety officer.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting rentals and sales in Boston

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Er, yeah, this is getting a bit beyond the scope I'd originally envisaged; if someone could give me all this about the UK situation I'd be pleased as punch.

In the main I suspect that the situation will be strikingly similar here, as it so often is, inasmuch as there'll be lots of laws, standards, codes and labyrinthine history, and not much guidance.

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On 1/15/2021 at 3:34 PM, Phil Rhodes said:

In the main I suspect that the situation will be strikingly similar here, as it so often is, inasmuch as there'll be lots of laws, standards, codes and labyrinthine history, and not much guidance.

That about sums it up, and I haven’t even got into half of it. For example, Massachusetts now requires GFCIs on outdoor set lighting of 150 V or less, and 50 A or less (Section 210.8 (B)(4)). Whereas the City of Los Angeles, where much production takes place, exempts outdoor sets from the requirement for ground-fault protection with GFCIs. How two AHJs, on opposite sides of the country, can come to opposing positions says a lot about the nature of the Code. Let’s explore how it came to this, its ramifications for the distribution of power on set, and what we can do about it.

The benefit of using GFCIs is indisputable. According to research done by the National Electrical Manufacturers Association, household electrocutions have fallen in proportion to the number of GFCIs being used from 1976 to 2001. So, it was inevitable that during the 2020 Code review cycle, there would be a general agreement among Code panel members that GFCIs should be used more widely. A spate of electrocution accidents—a child in Oklahoma retrieving a pet from behind a clothes dryer, a 10-year-old Houston boy playing hide-and-seek, a 12-year-old in Chicago being electrocuted when he touched an AC condenser unit with an electrical fault—sealed the deal resulting in the 2020 Code setting a higher standard across more areas of the Code. For instance, Section 210.8(B)(4) now requires GFCI protection for all outdoor outlets supplied by branch circuits rated 150 V to ground or less, 50 A or less. This update extends the GFCI requirement to include all fixed or portable power connections outdoors—even hard-wired equipment outdoors, like AC compressors.

Since there are no readily available dimmer rated Class A GFCIs, Code Panel 15 (which includes mainly LA entertainment industry representatives), sought and was granted an exemption to Section 210.8 in Article 530, motion Picture and television Studios and Similar Locations. This exemption would be good news for us if not for the fact that Article 530, is widely interpreted by AHJs outside California to mean that it does not pertain to location filming. Section 530.2 defines a “Motion Picture Studio” as:

“A building or group of buildings and other structures designed, constructed, or permanently altered for use by the entertainment industry for the purpose of motion picture or television production.”

And a “Shooting Location” as:

“A place outside a motion picture studio where a production or part of it is filmed or recorded.”

So, by definition they are not the same occupancy. Many AHJs take this to mean that the exemption to Section 210.8 permitted by Article 530 does not extend outside the confines of a stage.

LA County, by comparison, extends the Article 530 exemption to include location filming outdoors. that’s because the AHJs in California interpret the intent of the Code so that obtaining a location permit temporarily changes the occupancy of a location to a “motion picture studio.” This simple provision accommodates a local industry while keeping the Code in force generally. Why not grant the LA film industry an exemption? With an average annual rainfall of only 14", the likelihood of receiving a lethal electrical shock while working outdoors is much lower in Los Angeles than it is in Massachusetts where the average annual rainfall is three times greater (43"). This is just one example, of many across the country, of an AHJ modifying the code to suit the needs of a local industry. So, despite its authoritative position and having “National” in its title, NEC standards are merely a template local governments use to create and enforce their own electrical code that meets their own needs.

This leaves us here in Massachusetts with a problem: Section 210.8(4)(B)) applies to outdoor location filming—not only to craftie and video-village, but also to small cord set lighting as well. Unless the Code is revised, our dilemma will eventually become your dilemma as the 2020 Code is adopted by more states and municipalities across the country. Aware of the potential downside for motion picture production across the country, an industry trade group has formed to advise Code Panel 15 to make explicit in the 2023 Code that Article 530 exemptions extend to production on location as well as in the studio, but until then we are stuck with this Article 210 requirement to use GFCIs on small cords outdoors. This presents set lighting technicians with a challenge: the readily available inline GFCI dongles you get at hardware stores are prone to nuisance tripping with motion picture lighting loads and are only rated for 15 A, not 20 A.

The residual currents generated by the electronic power supplies used in HMIs, fluorescent luminaires, and now LEDs sensitize these GFCIs so that they are very susceptible to tripping. To improve the generally poor reliability of GFCIs, in 2003 UL published a new standard for GFCIs (UL 943) designed to prevent nuisance tripping by transient conditions that are not of a sufficient duration to pose a hazard. The new standard allows GFCIs to trip on an “Inverse Time Curve.” An inverse time curve introduces a delay that decreases as the magnitude of the current increases. The delay allows transient conditions that do not pose a hazard to pass without tripping the GFCI. UL 943 also permits GFCIs to filter high-frequency currents to eliminate residual currents and thereby further reduce nuisance tripping.

Even though the UL 943 standard was meant to enable GFCIs to operate more reliably in real world conditions, manufacturers of inexpensive Class A GFCIs, like those found in hardware stores, do not implement the UL 943 curve because it requires sophisticated micro-processors, which makes the GFCI much more expensive. For the same reason, they do not filter high-frequency residual currents. They use a more aggressive response than required by UL 943 (typically 250 ms at 6 mA where UL 943 permits 5.59 seconds).

This more aggressive trip curve and lack of filtration does not generally pose a problem in the one-tool per circuit applications for which hardware store GFCIs are designed. However, the more aggressive trip curve of this style of GFCI has proven to be a problem in applications involving non-linear lighting loads, (the lights increasingly being used in motion picture production and event staging.) So, what’s a set electrician to do?

Fortunately, NEC Section 215.9, Ground-Fault Circuit-Interrupter Protection for Personnel provides general permission for a feeder to be GFCI protected where it supplies 15 A and 20 A branch circuits requiring GFCI protection under Section 210.8. the section reads as follows:

“Feeders supplying 15- and 20-ampere receptacle branch circuits shall be permitted to be protected by a ground-fault circuit interrupter in lieu of the provisions for such interrupters as specified in 210.8 and 590.6(A).”

Since this section prescriptively identifies feeder GFCI protection “in lieu of,” it permits the use of “film style” GFCIs with 100 A Lunch Boxes to satisfy the expanded Section 210.8 requirement for GFCI protection on all branch circuits rated 150 V to ground or less, 50 A or less.

This is good news for us. Film style GFCIs, like the Lifeguard, Shock Block, or Shock Stop  are a lot less prone to nuisance tripping because they employ high-frequency filters and a trip curve that more closely approximates the inverse-time curve of UL 943. (use this link for more detailed information on the benefits to using film-style GFCIs on set).  

So, given the variety of code interpretations, it is important to always check with the local AHJ for regional differences from the national Code.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting rentals and sales in Boston

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This makes me think I should make up some small distribution units with RCDs in them, even for very small shoots that might run a couple of cables around someone's back yard.

("RCD" means "residual current device," to wit, a GFCI by any other name.)

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On 1/30/2021 at 11:18 AM, Phil Rhodes said:

This makes me think I should make up some small distribution units with RCDs in them, even for very small shoots that might run a couple of cables around someone's back yard.

("RCD" means "residual current device," to wit, a GFCI by any other name.)

We got a couple of these 100 amp GFCI Lunch Boxes https://www.kayelites.com/osc/product_info.php/products_id/6224 on my last job and rented them to the show

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On 2/4/2021 at 10:44 PM, JB Earl said:

Phil, I use some inline 20 amp GFCI's that are commercially available  (120v)  made by Voltec

The problem with this type of industrial GFCI is that they are prone to nuisance tripping with HMIs, Kinos, & LEDs. To improve the generally poor reliability of early GFCIs, in 2013 UL revised the standard for GFCIs to allow them to trip on an “inverse time” curve. An inverse time curve introduces a delay that decreases as the magnitude of the current increases. The advantage to an inverse time trip curve is that it permits a transient imbalance that is sufficiently short in duration so as not to pose a danger to pass while keeping current through the body to safe levels. To assure the latter, UL943 requires that as fault current increases the maximum allowable time to open a circuit decreases, with an almost instantaneous response time required (no more than 20 milliseconds) if the fault current is greater than 300 mA compared to 5.59 seconds at 6 mA. In other words, the higher the current, the faster the GFCI must trip. The advantage of UL943’s trip curve is that it minimizes nuisance tripping from surges in residual current while providing protection from shocks.

The manufacturers of industrial GFCIs like these choose not to use the more accommodating UL943 safety curve because it requires sophisticated microprocessors, which makes their product more expensive. Instead, they use a more aggressive response that is lower and faster than that required by UL943 (typically 250ms at 6mA where UL943 permits 5.59 seconds at 6mA.) The more aggressive response of these GFCIs is permissible because the UL943 standard is the absolute highest current vs. time response allowed but it is not mandatory. That is, a device will fail UL testing if it responds slower than the standard requires; but will pass if the response time is less than the standard requires, even if it is a lot less. While the more aggressive trip curve of industrial GFCIs does not generally pose a problem in the one-tool-per-circuit application for which they are designed, it has proven to be a problem in electrically noisy environments like motion picture production.  “Film” GFCIs, like LifeGuards, Shock Blocks, and Shock Stops use sophisticated (read expensive) micro-processors to trip more closely to the UL inverse time curve and so are more forgiving of transient surges caused by switching on other lights, which greatly reduces nuisance tripping.

Industrial GFCIs like these are also prone to nuisance tripping with lighting loads because they do not filter out harmonic currents. Non-linear lighting loads (HMIs, Kinos, & LEDs – the predominant loads these days) by design leak a small amount of harmonic current to the equipment grounding conductor called ‘residual current.”  If the GFCI does not incorporate filtration of harmonic currents (most all industrial GFCIs do not), these residual currents will nuisance trip the GFCI. For that reason, it is important to use “film” GFCIs that incorporate low band pass filters to filter residual currents (the GFCIs you get at hardware stores do not because they make the GFCI even more expensive.) Use this link for more details.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

 

 

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On 2/5/2021 at 11:24 AM, Kyle Perritt said:

We got a couple of these 100 amp GFCI Lunch Boxes https://www.kayelites.com/osc/product_info.php/products_id/6224 on my last job and rented them to the show

This is a good case in point why electrical distribution should be left to qualified persons. As you may recall from my post above, NEC Article 530 requires that an individual using portable lighting and power distribution equipment know how to comply with NEC safety rules when performing installations. The NEC Section 100 definition of a GFCI is a “Class A device” as specified by UL943. Among UL943’s many requirements is that portable GFCIs trip if there is a break in the line side neutral conductor of a circuit. It does not require the same of GFCIs meant to be permanently installed in a wall outlet box. Since the GFCI Lunch Boxes you bought from Kayelites incorporate wall box style GFCIs without open neutral protection they do not meet the code requirement for the use of portable GFCIs outdoors.  (For the same reason Phil’s shop made RCD boxes would not pass US code.) A qualified person, trained in ground fault protection, would know the difference between GFCIs suitable for portable use and permanent installation.

The same is true of OSHA.  OSHA29 CFR 1926.404(b)(1)(i) states:

“The employer shall use either ground fault circuit interrupters as specified in paragraph (b)(1)(ii) of this section or an assured equipment grounding conductor program as specified in paragraph (b)(1)(iii) of this section to protect employees on work sites . . .”

Under §1926.404(b)(1)(ii), when using GFCIs to comply with paragraph (b)(1)(i), the employer must use an "approved" GFCI. Under §1926.449, approved equipment is equipment that is "acceptable." Section 1926.449(a) defines acceptable equipment as follows:

“(a) If it is accepted, or certified, or listed, or labeled, or otherwise determined to be safe by a qualified testing laboratory (like UL) capable of determining the suitability of materials and equipment for installation and use in accordance with this standard…”

As I mentioned previously, UL requires portable GFCIs to offer protection against an open-neutral condition.

Why the different requirements for portable vs. permanently installed GFCIs? Since portable GFCIs are likely to be used on wiring of questionable integrity, such as the temporary power systems of construction sites or the portable power systems of motion picture sets, UL943 requires portable GFCIs to interrupt power to the load if there is a break in the line side neutral conductor. Given the wear and tear equipment receives in these environments, it is more likely that one of the circuit conductors could be broken on the supply side of the GFCI. If it is the energized, or Hot, conductor that is broken, no hazard exists at the GFCI, and it is readily obvious because there is no power.

If, however, it is the grounded circuit conductor, or neutral, that is broken on the line side of the GFCI, it is less obvious. The line voltage terminals would still be energized. The only indication of an open neutral would be that a load plugged into the circuit doesn’t turn on. Since the brain of the GFCI relies on a complete circuit in order to operate, under this circumstance the GFCI would not trip if there were a ground fault on its load side. Of course, the problem would be detected if the unit were tested with the test button before each use as required by Code, but we know that precaution is seldom taken.

It is because of this possible hazard that UL943 requires that the load terminals of portable GFCIs must be de-energized when the neutral is interrupted on the line side of the device. Portable GFCIs accomplish this by using “NO”, or normally open, relays rather than the more common “NC”, or normally closed, relays. With NO relays power must be complete to the relay in order for the contacts to be closed. If there is no power, such as from an open neutral, the relay contacts are opened by spring pressure. Power is necessary to overcome the spring pressure, closing the contacts.

Sorry to say that your GFCI Lunchbox is not a UL approved Class A GFCI and therefore does not meet Code where a Class A GFCI is required.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting equipment rental and sales in Boston

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What's really subjectively alarming to me is the fact that people use those shockingly feeble little 110V connectors on film sets. We're spoiled in the UK - even our domestic mains connectors are indestructible hunks of plastic and metal, almost to a fault - but we don't even use those outdoors!

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17 hours ago, Guy Holt said:

This is a good case in point why electrical distribution should be left to qualified persons. As you may recall from my post above, NEC Article 530 requires that an individual using portable lighting and power distribution equipment know how to comply with NEC safety rules when performing installations. The NEC Section 100 definition of a GFCI is a “Class A device” as specified by UL943. Among UL943’s many requirements is that portable GFCIs trip if there is a break in the line side neutral conductor of a circuit. It does not require the same of GFCIs meant to be permanently installed in a wall outlet box. Since the GFCI Lunch Boxes you bought from Kayelites incorporate wall box style GFCIs without open neutral protection they do not meet the code requirement for the use of portable GFCIs outdoors.  (For the same reason Phil’s shop made RCD boxes would not pass US code.) A qualified person, trained in ground fault protection, would know the difference between GFCIs suitable for portable use and permanent installation.

The same is true of OSHA.  OSHA29 CFR 1926.404(b)(1)(i) states:

“The employer shall use either ground fault circuit interrupters as specified in paragraph (b)(1)(ii) of this section or an assured equipment grounding conductor program as specified in paragraph (b)(1)(iii) of this section to protect employees on work sites . . .”

Under §1926.404(b)(1)(ii), when using GFCIs to comply with paragraph (b)(1)(i), the employer must use an "approved" GFCI. Under §1926.449, approved equipment is equipment that is "acceptable." Section 1926.449(a) defines acceptable equipment as follows:

“(a) If it is accepted, or certified, or listed, or labeled, or otherwise determined to be safe by a qualified testing laboratory (like UL) capable of determining the suitability of materials and equipment for installation and use in accordance with this standard…”

As I mentioned previously, UL requires portable GFCIs to offer protection against an open-neutral condition.

Why the different requirements for portable vs. permanently installed GFCIs? Since portable GFCIs are likely to be used on wiring of questionable integrity, such as the temporary power systems of construction sites or the portable power systems of motion picture sets, UL943 requires portable GFCIs to interrupt power to the load if there is a break in the line side neutral conductor. Given the wear and tear equipment receives in these environments, it is more likely that one of the circuit conductors could be broken on the supply side of the GFCI. If it is the energized, or Hot, conductor that is broken, no hazard exists at the GFCI, and it is readily obvious because there is no power.

If, however, it is the grounded circuit conductor, or neutral, that is broken on the line side of the GFCI, it is less obvious. The line voltage terminals would still be energized. The only indication of an open neutral would be that a load plugged into the circuit doesn’t turn on. Since the brain of the GFCI relies on a complete circuit in order to operate, under this circumstance the GFCI would not trip if there were a ground fault on its load side. Of course, the problem would be detected if the unit were tested with the test button before each use as required by Code, but we know that precaution is seldom taken.

It is because of this possible hazard that UL943 requires that the load terminals of portable GFCIs must be de-energized when the neutral is interrupted on the line side of the device. Portable GFCIs accomplish this by using “NO”, or normally open, relays rather than the more common “NC”, or normally closed, relays. With NO relays power must be complete to the relay in order for the contacts to be closed. If there is no power, such as from an open neutral, the relay contacts are opened by spring pressure. Power is necessary to overcome the spring pressure, closing the contacts.

Sorry to say that your GFCI Lunchbox is not a UL approved Class A GFCI and therefore does not meet Code where a Class A GFCI is required.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting equipment rental and sales in Boston

Good to know

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17 hours ago, Guy Holt said:

This is a good case in point why electrical distribution should be left to qualified persons. As you may recall from my post above, NEC Article 530 requires that an individual using portable lighting and power distribution equipment know how to comply with NEC safety rules when performing installations. The NEC Section 100 definition of a GFCI is a “Class A device” as specified by UL943. Among UL943’s many requirements is that portable GFCIs trip if there is a break in the line side neutral conductor of a circuit. It does not require the same of GFCIs meant to be permanently installed in a wall outlet box. Since the GFCI Lunch Boxes you bought from Kayelites incorporate wall box style GFCIs without open neutral protection they do not meet the code requirement for the use of portable GFCIs outdoors.  (For the same reason Phil’s shop made RCD boxes would not pass US code.) A qualified person, trained in ground fault protection, would know the difference between GFCIs suitable for portable use and permanent installation.

The same is true of OSHA.  OSHA29 CFR 1926.404(b)(1)(i) states:

“The employer shall use either ground fault circuit interrupters as specified in paragraph (b)(1)(ii) of this section or an assured equipment grounding conductor program as specified in paragraph (b)(1)(iii) of this section to protect employees on work sites . . .”

Under §1926.404(b)(1)(ii), when using GFCIs to comply with paragraph (b)(1)(i), the employer must use an "approved" GFCI. Under §1926.449, approved equipment is equipment that is "acceptable." Section 1926.449(a) defines acceptable equipment as follows:

“(a) If it is accepted, or certified, or listed, or labeled, or otherwise determined to be safe by a qualified testing laboratory (like UL) capable of determining the suitability of materials and equipment for installation and use in accordance with this standard…”

As I mentioned previously, UL requires portable GFCIs to offer protection against an open-neutral condition.

Why the different requirements for portable vs. permanently installed GFCIs? Since portable GFCIs are likely to be used on wiring of questionable integrity, such as the temporary power systems of construction sites or the portable power systems of motion picture sets, UL943 requires portable GFCIs to interrupt power to the load if there is a break in the line side neutral conductor. Given the wear and tear equipment receives in these environments, it is more likely that one of the circuit conductors could be broken on the supply side of the GFCI. If it is the energized, or Hot, conductor that is broken, no hazard exists at the GFCI, and it is readily obvious because there is no power.

If, however, it is the grounded circuit conductor, or neutral, that is broken on the line side of the GFCI, it is less obvious. The line voltage terminals would still be energized. The only indication of an open neutral would be that a load plugged into the circuit doesn’t turn on. Since the brain of the GFCI relies on a complete circuit in order to operate, under this circumstance the GFCI would not trip if there were a ground fault on its load side. Of course, the problem would be detected if the unit were tested with the test button before each use as required by Code, but we know that precaution is seldom taken.

It is because of this possible hazard that UL943 requires that the load terminals of portable GFCIs must be de-energized when the neutral is interrupted on the line side of the device. Portable GFCIs accomplish this by using “NO”, or normally open, relays rather than the more common “NC”, or normally closed, relays. With NO relays power must be complete to the relay in order for the contacts to be closed. If there is no power, such as from an open neutral, the relay contacts are opened by spring pressure. Power is necessary to overcome the spring pressure, closing the contacts.

Sorry to say that your GFCI Lunchbox is not a UL approved Class A GFCI and therefore does not meet Code where a Class A GFCI is required.

Guy Holt, Gaffer, ScreenLight & Grip, Lighting equipment rental and sales in Boston

I completely screwed that up.... the ones on our truck are the Guardians, which are definitely Class A

The Kaye Lites just looks almost identical to it. I apologize to Phil for posting a link to a terrible product. This is the real thing 

* I'm not the one making these orders so, was easy for me to get fooled by the image of the knock off after a long day *

https://www.guardiangfci.com/products/lg520

 

 

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1 hour ago, Kyle Perritt said:

I completely screwed that up.... the ones on our truck are the Guardians, which are definitely Class A

The Kaye Lites just looks almost identical to it. I apologize to Phil for posting a link to a terrible product. This is the real thing 

* I'm not the one making these orders so, was easy for me to get fooled by the image of the knock off after a long day *

https://www.guardiangfci.com/products/lg520

 

 

That looks the same exact product that is in the kay lites link.

Edit: ** It is the same product, Manufactured by AC Power 

Kaylites' description: Manufacturer AC POWER

Guardian's Description: "
Our friends over at AC Power helping the Bender team out doing what they do best! "

 

Edited by Ed Conley
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This certainly got confusing.

Guy, you claim that the Kay Lite lunches does not satisfy the GFI requirements but it is 

UL listed

UL943 by ETL

????
 
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Well, this has got some way beyond what I was asking about, but carry on!

I'll need to consult a UK person to answer the question for here, I suspect.

Still not sure when I actually start needing sparks, though!

P

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thanks for the detailed info Guy.  I looked at the manufacturers you cited, the only product I could find that is appropriate to what I'm doing would be the one by Lifeguard, https://www.guardiangfci.com/products/lg20-line.  I use the Voltec https://www.voltec-industries.com/copy-of-04-00103  for extremely small projects involving a couple lights. I haven't had a problem with them tripping (yet).  Typically I'll plug in a parcan or a couple litemats/panels.

I appreciate your thorough explanations, but can you give a non-electrician comparison of these 2 devices, and a dealer for the LG20 if you know of one?

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6 hours ago, Ed Conley said:

That looks the same exact product that is in the kay lites link.

Edit: ** It is the same product, Manufactured by AC Power 

Kaylites' description: Manufacturer AC POWER

Guardian's Description: "
Our friends over at AC Power helping the Bender team out doing what they do best! "

 

Well that's great that a company isn't selling a completely identical knockoff that isn't up to code

5 hours ago, Phil Rhodes said:

Well, this has got some way beyond what I was asking about, but carry on!

I'll need to consult a UK person to answer the question for here, I suspect.

Still not sure when I actually start needing sparks, though!

P

I'm somewhat optimistic that by page 5 of this thread, someone is going to come along with a simple and concise answer to your original question.  

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1 minute ago, Kyle Perritt said:

Well that's great that a company isn't selling a completely identical knockoff that isn't up to code

I'm somewhat optimistic that by page 5 of this thread, someone is going to come along with a simple and concise answer to your original question.  

Heh, I don't think there really is a concise answer to the question. Like a lot of things there's a huge grey area and there will be no one-sentence answer.

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7 hours ago, Phil Rhodes said:

Well, this has got some way beyond what I was asking about, but carry on!

I'll need to consult a UK person to answer the question for here, I suspect.

Still not sure when I actually start needing sparks, though!

P

Did you mean legally? Seems like a UK producer question, really.

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8 hours ago, Satsuki Murashige said:

Did you mean legally? Seems like a UK producer question, really.

As a camera guy I do (well, did, really) get asked a lot about who we needed.

I think in reality it's more of an insurance requirement than a legal one, but the insurance we were using was silent on the subject. This was insurance of a type I'm fairly sure doesn't exist in the USA, costing a few hundred. It's intended for very small, low-budget film shoots, covering employers' and public liability and equipment.

I'm not a lawyer. I don't know. But clearly people use portable equipment outdoors without any legal requirement to have any particularly qualified person; anyone using a power tool in the back yard is doing that. I don't know the answer.

I never once actually ended up with electricians, even on a couple of occasions where I really could have done with one; we muddled through. 

P

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