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Guy Holt

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  • Occupation
    Gaffer
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    Boston
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    Custom Honda generator systems for motion picture production including paralleling systems with 100A output.

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    http://www.screenlightandgrip.com

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  1. Sam, when there is a potential difference in charges between two points expressed in volts, current will flow if they make contact with each other and form a circuit. Since it takes only milliamps to electrocute someone, you can receive a lethal shock if you are the one making the contact. For this reason, the National Electrical Code (2014 NEC Article 250, Subsection 20(D)) requires that when two sources of power ("separately derived systems" in NEC parlance) are located within 20 feet of each other, or when one supplies equipment which might possibly come within 20 feet of equipment supplied by the other (unavoidable on a steel ship), the two sources of power must be bonded together so that they share a common ground point. Connecting to a common ground, creates a zero reference or zero potential difference, and eliminates touch potential, thereby eliminating the shock hazard. According to Code, the bonding conductor can be covered, insulated or bare and is not required to be installed with other circuit conductors or in a raceway. It must be solidly connected (expect the inspector to kick the connector) and metal-to-metal (so you may need to scrape off some paint.). Use the rating of the ship's largest circuit overcurrent device and 2014 NEC Table 250.122 to size the bonding conductor, keeping in mind that it cannot be smaller than 6 AWG. ANSI E1.19, Section 6.4.2 stipulates that "Class A GFCI protection shall be used on all 15 to 100 ampere 120-240 Volts AC, single and three phase receptacles and circuits where water or moisture is present or is likely to be present" which is just about everywhere on a ship. This may be the hardest requirement to comply with since, many HMI, Kino, and LED motion picture lights generate sufficient residual current to nuisance trip hardware store GFCIs and /or the GFCIs on the Honda. The solution is to use a small step-down transformer to convert the unprotected 30A-240V output of the Honda to a 60A-120V circuit, and a film-style 60A GFCI (like the Shock Stop 60-60IL.) The Shock Stop has a more forgiving trip curve and harmonic filtration to eliminate nuisance tripping from residual currents. Hardware store GFCIs and the GFCIs on the Honda do not. Another benefit to using a 60A step-down transformer/distro with the Honda is that it enables you to use standard film style distribution equipment (like 60A Bates Extensions, 60A Bates Siamesses (sp?), and 60A Bates-to-Edison breakout boxes) to distribute power around your set. And since 2020 NEC 215.9 permits an upstream feeder to be GFCI protected in lieu of the requirement for such interrupters on branch circuits (as specified in 2020 NEC210.8), a 60A Shock Stop just downstream of the transformer/distro will provide Code compliant GFCI protection of your entire distribution system. Another benefit to using a step-down transformer/distro is that it will enable you to run a 4k HMI on the Honda. For more detailed information on using small step-down transformer/distros and film style GFCIs to provide ground fault protection with portable Honda generators, I would suggest you read the article I wrote for our company newsletter on the use of portable generators in motion picture lighting. Of the article Harry Box exclaims: "Great work!... this is the kind of thing I think very few technicians ever get to see, and as a result many people have absolutely no idea why things stop working." "Following the prescriptions contained in this article enable the operation of bigger lights, or more smaller lights, on portable generators than has ever been possible before." The article is available online. The use of small step-down transformer/distros with portable Honda generators is also covered in the latest editions of Harry Box's Set Lighting TEchnician's Handbook and Blain Brown's Cinematography: Theory and Practice. Guy Holt, Gaffer, ScreenLight and Grip, Lighting & Grip Rental & Sales in Boston
  2. How do you know the switch is repaired? The switch may require adjustment after replacing the spring. The only way to confirm the safety switch is functional is to test continuity between the safety loop pins of the head pigtail with the door closed. If you read continuity, the switch is functional. If you don't read continuity, the switch needs adjustment. Guy Holt, Gaffer, ScreenLight & Grip, Lighting rental and sales in Boston
  3. Then you might consider paralleling two Honda EU7000s and using a step-down transformer to convert the combined 240V output to a 100A circuit at 120V, which is enough to power a 10K. Paralleled Honda EU7000s can also power an ARRIMAX 9k. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston
  4. For example, I have used this same package repeatedly at historical house/museums like the Ames Estate in Easton MA that has served as the location for numerous American Experience PBS historical biographies. A popular state fee free location, the Ames Estate, like many historical house/museums does not permit tie-ins and the electrical wiring is so antiquated that it is unusable. Fortunately, they have a 50A/240V circuit in the carriage house for a welder they use to repair the mowers they use at the park. Our standard mode of operations when shooting there is to run 250V extension cable from the 240V receptacle to a 60A HD Plug-n-Play transformer/distro in the entry hall of the house. Using a 60A Siamese at the transformer/distro, we then run 60A 6/3 Bates extensions, down to the library, to the second floor, and back to the maid's pantry. At the end of each run we put another 60A Siamese. A 60A snack box on one side of the Siamese gives us 20A branch circuits. The other side we leave open for a large HMI or tungsten light. Now we can safely plug HMIs up to 4K or tungsten up to 5k into our own distributions anywhere in the house to balance the interior levels to the exteriors and maintain continuity. A good example of this approach is an American Experience program titled "The Most Dangerous Women in America" about Typhoid Mary that I lit for PBS. For part of her life, Typhoid Mary was quarantined on an island in New York's East River. Because New York's East River today looks nothing like it did when she was in quarantine, we used a 30' blowup of a picture of the East River at the turn of the century rigged outside the windows of the house. We had to strike a delicate balance between the interior and exterior levels. We wanted to overexpose the exterior by one stope so that it would look realistic and hide the fact that the exterior was a blown-up picture. We rigged a 20x20 solid over the porch windows and the blow-up to keep the sun off both. That way we could light the blow-up and interior so that it remained consistent even though the sun moved on and off the porch in the course of the day. To take the edge off the blow-up, we used a single scrim outside the window to help throw it out of focus. To maintain continuity between shots, we brought a 4kw HMI Fresnel in a window on one side of the room as a sun source and a diffused 1200 par through a window on the other side as a northern light source. We powered both heads off the 240V receptacle in the garage using one of our 60A transformer/distros. The two 2.5k W Par lights used outside to light the blow-up were powered by a Honda EU6500 through a second 60A transformer/distro. Since the Honda could be placed right on the lawn, we were saved from running hundreds of feet of feeder back to a tow generator. I have been able to use this same basic package at numerous museums and historical houses throughout New England. Fortunately for us, to make ends meet, many historical houses rent themselves out for events and weddings. For that reason, they usually have at least one updated service with 30 or 50A 240V circuit for the warming ovens of caterers. For production stills from this show and other PBS and History Channel historical documentaries shot entirely , or in part, with just a couple of transformer/distros and a Honda use these links: http://www.screenlightandgrip.com/html/tmintro.html http://www.screenlightandgrip.com/html/unhisintro.html http://www.screenlightandgrip.com/html/franklinintro.html In my experience, every show requires slightly different lights but they all benefit by the additional power that can be accessed through 240V circuits with a step-down transformer, so you might consider investing in distribution equipment that you will use on every shoot rather than lights that you will only use on some. Besides, these days the older HMI Fresnels and Pars can be rented very cheaply. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Sales and Rental in Boston
  5. Don't impose artificial limitations on yourself. If by the "maximum I can work with in terms of power" you mean what you can plug into household electrical outlets you are imposing artificial limitations on yourself. If you expand your horizons to include 240V range and dryer plugs you can safely and legally power much bigger lights like tungsten 5ks and 4k HMIs. Regardless what LED manufacturers claim, I have yet to see a LED fixture that can match a 2.5 HMI Par. And as Aapo Lettinen correctly stated, LEDs can't match a tungsten light for color rendition at 3200K - especially skin-tones. As you get into lighting dramas you will need these larger lights to maintain continuity. You can safely and legally power any tungsten 5k or 4kHMI on a 240V wall outlet if you use a 240V-to-120V step down transformer like the one we manufacture for our modified Honda EU7000s inverter generator. A transformer converts the 240 volts supplied by industrial and household 240V receptacles back to 120V in a single circuit that is the sum of the two legs of the circuit. For instance, a transformer can make a 60A/120V circuit out of a 30A/240V dryer circuit that can power a 4k HMI or tungsten 5k. What makes it safe to plug a 4k HMI into a 240V outlet is that a transformer automatically splits the load of whatever you plug into it evenly over the two legs of the 240V circuit so that you have 100 percent phase cancellation. I use transformers not only to power big HMIs (2.5-4kW) and big tungsten (5kW), but also more smaller lights, in situations where a tie-in is not an option, and the budget doesn't permit for a tow generator. If you outfit the transformer like our HD Plug-n-Play Transformer/Distro, with a 60A Bates receptacle, you can use 60A Bates extension cables, 60-to-60 splitters, and fused 60A Bates-to-Edison breakouts (snack boxes) to run power around set - breaking out to 20A Edison outlets at convenient points rather than running stingers all over the place trying to find a separate circuit so that you don't trip a breaker. The best part about using a transformer/distro with a 240V receptacle in this fashion is that no matter where in the distribution system you plug in, the transformer automatically balances the additional load, so that you don't have to be an experienced spark to distribute power on set. Guy Holt, Gaffer, ScreenLight & Grip, Lighting & Grip Equipment Rental and Sales in Boston
  6. Time to revive this thread with some indie tricks-of-the-trade for lighting large rooms with drop ceilings. You don’t necessarily have to go to the expense of bouncing big HMIs into the ceiling. One of the biggest challenges in situations like this is getting light into the eyes of your talent. If you don't, your talent's eye will look dark and bruised because a very toppy bounce won't dig into their eyes. As an alternative, the OP may want to consider the approach we took on a short film called "Act Your Age" that takes place in a senior center (use this link to see production stills.) We hung 4'-4 Bank kinos with Opal coved below the fixture to make a "Bay Light." Coving the Opal under the light, redirects it so that it will dig into the talent’s eyes. And you can skirt the fixtures to keep the light off the white walls (something you won’t be able to easily do with a bounce source.) You may also want to consider using a combination of hard and soft light as we did here to create contrast in a situation where the practical lighting is usually very flat. For a hard light source, we powered a 4k Fresnel off the wall. Most schools have a 240V receptacle of some kind. Common 240V circuits in schools include, Copier receptacles, range receptacles, and special receptacles installed for air conditioners. The latest generation of 2.5/4k HMI ballasts will operate on either 120V or 208-240V and fit comfortably in these circuits. If you are using an older ballast that runs only on 120V, you can step-down a 240V circuit to 120V with a transformer. A step-down transformer will convert the 240 volts supplied by 240V receptacles to 120 volts in a single circuit that is the sum of the two single-phase legs of 30/50 amps each (60A usually). Now that you have a larger 120V circuit, you can operate larger lights like 2.5 or even 4k HMIs, or more smaller lights, than you could otherwise. A step-down transformer can do the same with the enhanced 7500W/240V output of a Honda EU7000is Generator. By giving you access to more "house power" through common 240V household outlets, a Transformer/Distro can eliminate the need for dangerous tie-ins or expensive tow generators (use this link for details.) As you can see from the production stills, we used a special drop ceiling hanger that enables you to use a drop ceiling like a studio grid. Use this link for more pictures of productions that used drop ceilings on location as if they were a studio grid. Another alternative is to cut ¼” Luan plywood to the size of the ceiling tiles and screw a baby wall-plate into it. Then replace the ceiling tiles with the plywood wherever you want to hang a light. Guy Holt, Gaffer, ScreenLight & Grip, Lightng Rental & Sales in Boston
  7. Not necessarily. One of the biggest challenges in situations like this is getting light into the eyes of your talent. If you don't, your talent's eye will look dark and bruised because a very toppy bounce won't dig into their eyes. As an alternative, you may want to consider the approach we took on a short film called "Act Your Age" that takes place in a senior center (use this link to see production stills.) We hung 4'-4 Bank kinos with Opal coved below the fixture to make a "Bay Light." Coving the Opal under the light, redirects it so that it will dig into the talent’s eyes. And you can skirt the fixtures to keep the light off the white walls (something you won’t be able to easily do with a bounce source.) You may also want to consider using a combination of hard and soft light as we did here to create contrast in a situation where the practical lighting is usually very flat. For a hard light source we powered a 4k Fresnel off the wall. Most schools have a 240V receptacle of some kind. Common 240V circuits in schools include, Copier receptacles, range receptacles, and special receptacles installed for air conditioners. The latest generation of 2.5/4k HMI ballasts will operate on either 120V or 208-240V and fit comfortably in these circuits. If you are using an older ballast that runs only on 120V, you can step-down a 240V circuit to 120V with a transformer. A step-down transformer will convert the 240 volts supplied by 240V receptacles to 120 volts in a single circuit that is the sum of the two single-phase legs of 30/50 amps each (60A usually). Now that you have a larger 120V circuit, you can operate larger lights like 2.5 or even 4k HMIs, or more smaller lights, than you could otherwise. A step-down transformer can do the same with the enhanced 7500W/240V output of a Honda EU7000is Generator. By giving you access to more "house power" through common 240V household outlets, a Transformer/Distro can eliminate the need for dangerous tie-ins or expensive tow generators (use this link for details.) As you can see from the production stills, with the right rigging equipment, you can use drop ceilings like a studio grid. Use this link for more pictures of productions that used drop ceilings on location as if they were a studio grid. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston
  8. If you are looking for a Power Quality Analyzer there are a number of options. At a list price of $1495, the Fluke 41B Power Quality Analyzer was Flukes’ entry level single-phase scope meter. It combined the ease of use of a digital multimeter, the visual feedback of an oscilloscope and the power of a harmonics analyzer in a single instrument. It provided numeric values for rms, peak and total harmonic distortion (THD) for the complex voltage and current waveforms generated by motion picture lights. A bar graph showed the distribution of harmonics in complex waveforms, while its scope provided a graphic representation of both voltage and current waveforms. I use the past tense because, unfortunately, the 41B has been discontinued. Flukes’ entry level scope meter is now the 43B Power Quality Analyzer which sells for about $3800. Besides offering all the same capabilities of the 41B, the 43B trends voltage, current, frequency, power harmonics and captures voltage sags, transients, and inrush current. As far as I know (Fluke’s product line is constantly changing) the 43B is the only instrument that combines the capabilities of a Power Quality Analyzer, a 20 MHz oscilloscope, a multi-meter and data recorder in a single tool. The next step up in Power Quality Analyzers in Fluke’s product line is the 434-II, which sells for about $6900. It offers all the same capability as the 43B, but for all three phases simultaneously. It also offers a cool bar graph screen that combines power quality parameters (RMS Voltages, Harmonics, Flicker, Dips, Interruptions, Rapid Voltage Changes, Swells, Unbalance, Frequency, Mains Signaling) all on one screen. The length of a bar increases if the related parameter is further away from its nominal value. The bar turns from green to red if an allowed tolerance requirement is violated. These two options have several drawbacks. They are expensive but are available for rental in major markets. Their screens are poorly designed and exhibit dead scan lines after a while. The dead scan lines don’t affect their measuring capability, so they are just a nuisance. The screens can be swapped out for a couple hundred bucks at independent service shops (Fluke charges a lot more). The final drawback is that they are cluttered with features that have no benefit to set lighting technicians. The latest in metering technology designed specifically for set lighting technicians is GenNet IoT. Employing the latest Internet of Things (IoT) technology, GenNet IoT provides an unprecedented level of accessibility to the critical information required to manage generators and power distribution by delivering it to an operator’s phone, tablet, or laptop via 4G LTE wireless technology. It has an embedded web server that can display not only comprehensive power quality measurements but also engine data using standard internet browsers and allows for device configuration from the browser. To help you interpret the vast amount of information it generates (such as phase loading, voltage and power levels, power factor, and power quality measurements), its embedded web server presents real time, historical, and event information in easily understandable browser-style graphic displays. If a generator is equipped with InteliVision 5, GenNet IoT will also display critical engine data such as oil pressure, fuel level, and water temperature. To alert operators to problems before they can get out of hand, GenNet IoT also offers configurable event triggers. Max/Min limits can be set for any measured parameter. If any of the limits are exceeded, GenNet IoT will dispatch an e-mail alarm alerting you of the event. For example, to alert operators of a voltage unbalance that can degrade the performance of a generator and connected loads, its web server displays numerical and graphic phasor representations of the voltage of each phase, its phase angle, the average voltage, and will push an email alarm to your mobile device if the % (-) sequence harmonics (VNeg) exceeds two percent. Gen Net IoT’s email alarms can be a show saver for set lighting technicians since it is easy to miss load induced power quality issues in the thrash to get the first shot of the day. Gen Net IoT can also be used to prevent engine failure in Tier 4 generators caused by “wet stacking.” Wet stacking is the build-up of carbon in a generator’s engine caused by light loading. Generators need to operate at high temperatures to completely burn diesel fuel. When run under light loads, less heat is generated in its combustion chamber, leaving some fuel unburned. The unburned carbon coats the fuel injector nozzles, compromising their ability to adequately vaporize fuel. This, in turn, further lowers the combustion temperature and allows more unburned fuel to clog the fuel injectors. If left unchecked, wet stacking can result in premature engine failure. Operators of Tier 4 generators must be particularly vigilant. Tier 4 generators are more efficient, but they are also more vulnerable to the effects of light loading. They need to operate under higher loads (at least 75% of the nameplate rating) to reach the temperatures necessary to prevent carbon buildup and engine failure. With the reduced loads characteristic of sets lit predominantly by LED fixtures, wet stacking is an increasing concern for operators of Tier 4 generators. GenNet IoT prevents wet stacking by controlling a digital load bank to “auto-load” a generator. It does so by a Modbus control signal over ethernet that will initiate a digital load bank to automatically apply load to a generator in a step fashion if the lighting load drops below 75%, and to decrease the load it applies if the combined load begins to exceed 75%. In this fashion, GenNet IoT assures that the generator is sufficiently loaded to prevent wet stacking and premature engine failure. A tremendous benefit with Tier 4 generators when operating under the reduced load of sets lit predominantly with LED fixtures. To take one more thing off the plate of a generator operator, GenNet IoT can also automate the process of ghost loading. To maintain voltage unbalance within a narrow range when the impedance of the system neutral is high, GenNet IoT can control a companion load bank manufactured by Simplex specifically for it. If GenNet IoT senses unbalanced phases, it will trigger the load bank to apply load to the low phase in 5kVAR load steps. In this fashion GenNet IoT can maintain balanced phases thereby reducing deleterious unbalanced voltages. To further customize the load bank for film production Simplex has engineered it to apply an inductive load rather than the resistive load of standard industrial load banks. An inductive load offers several benefits in motion picture production. Without the tremendous heat generated by resistive coils, an inductive load bank eliminates the requirement for loud cooling fans and is thereby nearly silent in operation which permits the generator to be closer to set. An inductive load also corrects the leading power factor of motion picture lights these days. HMIs, Kinos, and LEDs are capacitive loads that cause voltage to lead current. Typically ghost loading is required when powering sets lit predominantly by LEDs. By applying an inductive load, Gen Net IoT corrects the power factor of the system (by pulling voltage back in phase with current) while maintaining a 75% load on the generator to prevent wet stacking. One Gen Net IoT on its own provides unparalleled access to the critical info required to manage a generator. Multiple Gen Net IoTs in a wireless 4G network, provides the ability to manage multiple generators from a central location. When there is more than one operator, Gen Net IoT enables them to share data and work in shifts – allowing them to get needed rest during overnights. One drawback to GenNet IoT is that it is only available for rental (most lighting technicians couldn’t afford one anyway.) As part of their rental model, a GenNet IoT customer support technician also receives the email alarms and is on hand to offer advice on how to correct the problem. It’s a whole new world from when I started in this business thirty years ago. Guy Holt, Gaffer, ScreenLight & Grip, Lighting equipment sales and rentals in Boston. P.S. In the interest of full disclosure I am involved in the development of GenNet IoT and so get overly excited about its features.
  9. You are correct that without a neutral in their mains cable these ballasts will not contribute to the elevation of return current on the system neutral of a distribution system – only smaller non-pfc ballasts operating line-to-neutral will do that. But, elevated neutral current is not the only adverse effect the harmonic currents drawn by these ballasts have on a distribution system whether it is single phase or three phase. Ed has already pointed to one: they draw an excessive amount of power (72A) compared to a power factor corrected ballast (55A). Since this watt-less power does not contribute to illuminating a set, it effectively reduces the capacity of your service. But that is not all. The current they draw is severely distorted by their large smoothing capacitors, which only draw current during a very brief period as the voltage waveform peaks. Since the ballast draws power for only a brief period, it draws a spiked current waveform with a high crest factor and harmonic content. This distorted current will have an adverse effect on the distribution system whether it is single phase or three phase. First, since the load of the light is only on the peak of the voltage waveform, in high impedance systems like generators, voltage drop occurs only at the peak, resulting in the flat-topping of the voltage waveform in the entire distribution system. Which means all connected loads encounter a chopped voltage waveform. Since the switch-mode power supplies of smaller HMIs, Kinos, and LEDs also only draw current at the peak of the voltage waveform, they can be starved of power. Second, since the harmonic currents drawn by these ballasts oscillate at high frequencies they travel on the perimeter of conductors (skin effect). Since more current is traveling through less copper the effective resistance of the conductor increases leading to further voltage drop, but more importantly an exponential increase in I2R heat loss, resulting in the possible nuisance tripping of breakers, and the overheating of conductors and the generator stator. Power factor correction circuitry is expensive - adding up to 25% to the cost of a ballast. For this reason, the manufacturers of HMI ballasts only incorporate it where it is absolutely necessary. Now a days all HMI ballast greater than 4kw include power factor correction because it is essential to the reliable operation of the ballast and connected loads. Which means you will need to take several precautions in using them. First, oversize generators and transformers by a factor of two. Second, oversize your feeder cables. Finally watch out for voltage flat-topping using a digital mulit-meter or power quality analyzer like GenNet IoT that can read peak voltage as opposed to rms voltage (the rms value of flat-topped voltage is the same as a sinusoidal voltage waveform.) This is a complicated subject, I strongly recommend you read a series of articles I wrote for Protocol Magazine (the qtrly journal of ESTA) on Production Power on a Budget and Power Quality in the Age of LEDS available at our website at http://www.screenlightandgrip.com/html/hd_plug-n-play_pkg.html. Harry box cites these articles in the latest edition of his handbook. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston
  10. You can use the 1kW Iris lights without flicker. The reason that you get flicker from small filament bulbs (<5kW) is that at high speeds the camera will capture the changing intensity of the light output of the bulb as it rises and falls as the voltage waveform rises and falls. If you use three 1kW Iris where you would normally use one, and put each fixture on a separate phase of the power service, the light output between the three fixtures will be constant as each compensates for the drop in intensity of the other. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rentals & Sales in Boston
  11. No. It depends on the ballast. I have only been able to do limited testing of HMIs but for example an Arri 4k power factor corrected ballast dumps 16.22mA of current into the EGC while a Power Gems 4k non-power factor corrected ballast dumps only 2.47mA. In order to reduce the amount of RF emitted, UL permits but does not require manufacturers of electronic devices to capacitively couple high frequency harmonic currents to ground (UL1244, UL1950, UL3101.) To accomplish this, some but not all ballast manufacturers include a mains input filter to stop electrical noise from being passed in or out of the ballast via its mains lead. Such filters typically include a pair of small capacitors, one connected between the hot and earth and the other between the neutral and earth wires of the incoming mains. The value of the capacitors is chosen to snub the high frequency noise by shunting it to ground. As such, these RF filters can be a source of appreciable leakage current on the EGC. Arri shunts the noise their ballasts generate while apparently Power Gems does not (use this link for more details.) Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston.
  12. Not really supposed to market products on these boards. Contact me off list through message or at rentals@screenlightandgrip.com for details. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston
  13. Let's try this again. Use this link to Shock Stop's marketing material and training guide. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston.
  14. Use this link to Shock Stop’s marketing literature and training guide. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston.
  15. The GFCI outlets on portable generators are not portable. They are hardwired into the generator. UL943 requires open neutral protection of portable GFCIs because they are likely to be used on wiring of questionable integrity that could have an open neutral, such as the temporary power systems of construction sites or the portable power systems of motion picture sets. Where open neutrals with GFCIs can create hazardous conditions UL943 requires portable GFCIs to interrupt power to the load if there is a break in the line side neutral conductor. It is nearly impossible for the neutral conductor of a GFCI hardwired into a generator to break. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston.
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