Guy Holt

Lindsey, You make some assumptions here that are based on popular misconceptions regarding the use of HMIs with Honda generators. In the interest of full disclosure I should say at the outset that, besides being a professional gaffer, I run a rental house in Boston by the name of ScreenLight and Grip where we rent and sell Honda Generators, as well as Arri, Mole, and Joker HMIs with Arri, Power Gem, or the new Power to Light Ballasts. Based upon my extensive experience with HMIs and Honda generators, I would like to take this opportunity to correct some of the popular misconceptions regarding their use and answer a few of your questions. If you plan to use HMIs with portable generators there are a number of factors to bear in mind. You won't have flicker problems if you use one of Honda's EU series Inverter Generators. Honda's sine-wave inverter technology provides much higher quality power than conventional (non-inverter) generators. With a waveform distortion factor of less than 2.5%, the power generated by Honda’s EU series of generators is quite often better than what you get out of the wall outlet. The power these machines generate is rock solid with a frequency variance of only hundredths of a cycle - which eliminates the need for costly crystal governors. The Honda EU series generators provide true sine wave power with low enough distortion, and frequency stability, to power HMI's without problems. There is a popular misconception that you should only use electronic ballasts with portable generators. Where that is true with conventional generators without crystal governors, it is not true of inverter generators for the reasons above. In fact, besides the extra bulk and weight of magnetic ballasts, the smaller magnetic ballasts (575-2500W) offer the distinct advantage of being less expensive and drawing less power (once they have come up to speed) than the commonly available electronic equivalents. One down side to using magnetic ballasts is that you are restricted to using only the safe frame rates and shutter angles. Where this topic is discussed extensively elsewhere in this forum I won’t get into it here. Operating at 120V, a 1.2kw HMI with non-power factor corrected electronic ballast will draw 18-19 amps verses the 13.5 amps of a magnetic ballast. Another downside to magnetic ballasts is that you can’t load the generator to full capacity because you must leave “head room” for their higher front end striking load. When choosing HMIs to run off portable generators, bear in mind that a magnetic ballasts draws more current during the striking phase and then they “settle down” and require less power to maintain the HMI Arc. By contrast, an electronic ballasts “ramps up”. That is, its’ current draw gradually builds until it “tops off” - but it “tops off” with a considerably greater draw than a magnetic ballast “settles down” to. Insufficient head room can be a problem when striking a 1200Watt HMI on a EU2000is, or on one of the 20A circuits of a EU3000is or EU6500is, when other thing are already plugged into the generator as well. Without an additional load on its 20A circuit, any one of the Honda EU series generators will power either an electronic or magnetic ballast. A magnetic ballast offers the slight advantage that you can power another tungsten or fluorescent light on the generator once the HMI has already struck. While older HMIs with magnetic ballasts are less expensive to purchase or rent, there have been some very recent advances in HMI electronic ballast technology that make the newest ballasts worth the extra money when it comes to lighting with portable generators. For example the HMI ballast manufacturer Power to Light has introduced Power Factor Correction (PFC) into 1200 & 800 Watt ballasts. We are pairing these new ballasts with the Joker 800 and Mole 1200 pars. The Power to Light PFC 1200W electronic ballast draws only 11 Amps verses the 18 Amps required by standard electronic ballasts and the 13.5 Amps required by magnetic ballasts after they have struck. And, like conventional electronic ballasts the Power to Light PFC 1200W electronic ballast “ramps up”, but it “tops off” with a considerably less draw than a magnetic ballast. Where a Kino Flo Parabeam 400 draws only 2 amps, that 8 Amp difference between using the new Power to Light PFC 1200W electronic ballast and a standard 1200W electronic ballast, can mean the difference of running four Parabeam 400s on a portable generator or not. I think you would have to agree that being able to run four Parabeam 400s on top of a 1200W HMI is a major boost in production capability. It is a popular misconception that a Honda 6500 can run no more than a couple of 1200 HMIs. This misconception stems from the fact that there is just enough room on the 20A circuits of the generator for either a 1200W electronic ballast or “head room” for a 1200W magnetic ballast; while, there is not enough “head room” on the 30A/120V Twist-lock receptacle to accommodate the high front end striking load of a 2500W 120V magnetic ballast. While that is true when plugging the lights into the generator’s 120v receptacles, it is not true when plugging the same lights into the generator’s 240V twist-lock receptacle through a 240V-to-120V step-down transformer. A step down transformer gives you access to the full power of the generator in a much larger 120V circuit that is capable of powering larger lights or more smaller lights than you can power off the generator’s 120V receptacles. For example, we have developed a 60A full power transformer that doubles as a distribution panel, that when used with a Honda EU6500is we modify, provides 7500 Watts in a single 120V circuit. Part of the reason our modified Honda EU6500is is capable of powering larger HMIs is that the larger circuit created by the transformer provides enough head room to accommodate not only the front end striking load of 2500W 120V magnetic ballasts, but also 4000W 120V magnetic ballasts as well. Our modified Honda 6500W generator can power these bigger HMIs, because the transformer splits the load evenly over the two legs of the 240V circuit of the generator. By splitting the large front end striking load of larger HMIs, the transformer reduces the impact on the generator when you first switch on the light. The load of the light is split into two smaller loads that require less “head room.” The same holds true when you switch on large tungsten lights like 5ks. Our 60A Full Power Transformer/Distro also enables you to more fully utilize the continuous rated power capacity of the EU6500is by enabling you to load it more fully. Without a transformer you can never fully utilize the available power of a portable generator because the load of a light has to go on one circuit/leg of the generator or the other. For example, when plugging lights into the power outlet panel of a Honda 6500, you reach a point where you can't power an additional 1kw light because there is not 8.4 amps available on either one of the factory installed 20A outlets/leg of the generator. With a transformer you can still add that 1kw light because the transformer splits the load evenly over the two legs (4.2A/leg) of the generator. Now that you are able to fully load the generator in a perfectly balanced fashion with the help of a transformer, you are able to not only power more smaller lights than you could without it, but also larger lights. For example our 60A Full Power Transformer/Distro is capable of powering 4kw HMIs, 6000W Molepar Six Lights, Quartz 5k, or a complete lighting pkg. When you add up the incremental savings of using only PFC HMI ballasts, and add that to the extreme power efficiency of the latest fluorescent and LED lights, you will find you can run a lot on a portable generator with a transformer. For example, our modified Honda EU6500is Generator with our 60A Full Power Transformer/Distro is capable of powering a 2.5kw Par along with a 1200 and 800 Par, plus a couple of Parabeam 400s, a couple of Parabeam 200s, and a Kino Flo Flat Head 80. Given the light sensitivity of HD Camcorders, this constitutes a complete location lighting package for HD Digital Cinema productions and more than enough light for your night exterior reshoots. Running a Honda EU6500is out of the back of your grip truck or van with the back facing away from set is usually all the blimping you need if you use the "Eco Throttle" feature of the generator. There is a popular misconception that you should turn off the "Eco Throttle" to start large loads such as HMI's. In my experience, Honda’s "Eco Throttle" can handle even 6k HMIs. As long as the light is powered by an electronic ballast, Honda’s "Eco Throttle" can handle the load of the ballast because it “ramps up” gradually over the 3-5 second striking phase as discussed above. Honda’s "Eco Throttle" has no problems handling sudden large tungsten loads when applied through a transformer like our 60A Full Power Transformer/Distro because the transformer splits the load and reduces the impact on the generator. You always want to use the "Eco Throttle" feature of the EU series generators because it is what makes the generators so much quieter than conventional portable generators. The “Eco-Throttle” automatically adjusts the generator's engine speed to produce only the power needed for the application in use. Traditional generators have to run at a constant 3600 RPM to produce the stable 60 hertz (cycle) electricity required for HMIs. Whereas, the Inverter Technology of the Honda Inverter Generators enables them to run at much slower RPMs while maintaining frequency and power for the requested load. Because the engine does not have to run at full speed constantly, the engine is much quieter. Honda's inverter generators are substantially quieter than traditional models. By utilizing a new separate triple chamber construction, a new centralized intake/exhaust system and the new Eco-Throttle design, the EU6500is achieves a noise reduction of ten decibels and is half as loud as the comparable EM7000is and ES6500 generators typically found at lighting rental houses. Honda's EU Series generators operate at 34 to 44 dBA at 50 ft. - well below what is required for trouble free location recording and quieter than our Crawford 1400 Amp “Movie Blimped” Generator. An advantage to using a step down transformer with a portable generator is that it eliminates multiple stinger runs because it puts your plug-in points conveniently close to set. To record sync sound without picking up any generator noise, all you need to do is add 100' of heavy duty 250V twist-lock cable between the van/truck with the generator and the transformer/distro. A single run of heavy duty 250V twist-lock cable will replace multiple stinger runs to the generator and eliminate the subsequent drop in voltage from line-loss from using standard electrical cords. We equip our 60A Full Power Transformer/Distro with the industry standard 60A/120V GPC (Bates) receptacle so that we can use standard film style distribution equipment. With additional 60A GPC extension cables, 60-to-60 Splitters, and fused 60A GPC-to-Edison Breakouts (snack boxes) our 60A Full Power Transformer/Distro enables you to run power around your set - breaking out to 20A Edison outlets at convenient points. The best part 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. With our modified Honda EU6500is generator, you simply plug in lights until the load wattage displayed on the iMonitor of the generator control panel reaches 7500 Watts. An overload alarm on the iMonitor display will tell you if you inadvertently overload the 60A Transformer/Distro. If it sounds like I’m hyping the Honda EU6500is generator, it is not because we rent and sell them. As a Gaffer of a lot of tight budgeted historical documentaries for PBS’ American Experience and the History Channel, it is my professional opinion that when used with step down transformers these machines are a major advance in portable power (use this link for more information about using transformers with portable gas generators: http://www.screenlightandgrip.com/html/hdfilmstrip4lg.html.) Your footage looks good given what you had to work with. But, imagine what your scene could look like if you lit it with a 2.5kw Par, a 1200, a 800 Par, plus a couple of Parabeam 400s, a couple of Parabeam 200s, and a Kino Flo Flat Head 80. - Guy Holt, Gaffer, Owner/Operator of ScreenLight & Grip – a lighting and grip equipment rental, sales, and production service company in Boston.

You have to be really careful when using dryer plugs as you have described. Yes, under certain conditions you can use them to power lights. If you look at the breaker of these circuits on the house distro panel you will notice that they use two pole breakers. Each pole of the breaker is in a sense an independent 30A/120 volt circuit. That is, if you measure the voltage from each pole of the breaker to ground it will be 120 volts, and if you measure the voltage between the two poles of the breaker you will notice that it is 240 volts. The 120 volts of the two poles adds up to 240V because the 120V circuits are on opposing legs of the single phase electrical service of the house and are therefore additive. In residential settings, this is how higher voltages are supplied to household appliances like Dryers, Electric Ranges, Air Conditioners, Motors, etc. that require more power than can be reasonably supplied by a single 120V circuit. Where each pole of the breaker is in a sense an independent 30A/120 volt circuit, you can split them out in a distro system but only under limited situations. The one situation where it is possible to use dryer plugs to power lights is when the dryer circuit is a four wire system (the receptacle has for slots: one for ground, one for neutral, and two for hot) and it is a single phase service. Where you can run into trouble is when the dryer circuit uses a three wire system (the receptacle has three slots: one for ground, and two for hot, and no neutral), or it is a three phase service. Many household and industrial 240V receptacles use a three wire system (no neutral) because they are meant to power single phase motors or heating elements that draw a perfectly balanced load and return no current because the single phase service legs are 180 degrees out of phase and cancel each other out – hence there is no need for a neutral return. You run into trouble with this kind of circuit when you start to pull an unbalanced load on your distro system. And, where under most production situations you can never perfectly balance your lighting load, the two 120V circuits that make up this 240V circuit (as described above) will not have 100% phase cancellation and the extra current of the high leg will not have a safe return path. The only way to pull power from three wire 240V circuits that meets code is to run your lighting load through a 240v-to-120v step down transformer. A transformer converts the 240 volts supplied by these industrial and household 240V receptacles back to 120 volts 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 circuit that is capable of powering bigger lights, like a 5k. What makes it safe to use a step town transformer with three wire 240V dryer/range/motor circuits is that the transformer automatically splits the load of whatever you plug into it evenly over the two legs of the 240V circuit. Where there is no high leg, the loads on each leg of the 240V circuit cancel out and there is no return that would require a separate neutral. Use this link - http://ls.cinematography.net/read/messages?id=148478 - to a recent thread on CML on this same topic. By giving you access to more house power through common 240V house outlets, a transformer can quite often eliminate the need for tie-ins or generators. Guy Holt, Gaffer, ScreenLight & Grip, Boston

Unless you have to shoot in a moving car, I would agree that your best bet would be to use a generator. Portable gas generators have come a long way since the Honda EX5500 with Crystal Sync. Honda now makes a 6500W Inverter generator (the EU6500is) which we modify to provide 7500 Watts of power in a single 120V circuit when used with a special distro we have developed. With the right lighting package that 60A/120V circuit can go a long way toward lighting your parking lot given the extreme light sensitivity of chips these days. If your shooting in a moving car, you would be better served by a “Battverter” rig. A “BattVerter” is a Battery/Inverter system designed to provide AC power from DC Batteries. Your area rental house might have the Kino Flo system. We offer a variety of BattVerters - from a compact turnkey 750W BattVerter to the 1800W battery/inverter rig we custom built to power four 4’ – 4 Bank Kino Flo Fixtures on an Airport Shuttle for the feature film “Shuttle” (use the link below for more details). You can get everything you need to build a battverter at your local marine supply store. You need a DC power source (deep cycle Marine Cells work best), a DC-to–AC True Sine Wave Power Inverter, and a Battery Charger (to top off the charge on the batteries between takes). Wire these components into an equipment case and you can put it on the floor of the back seats or in the trunk of the car. I would suggest making up a lightweight "jumper cable" that you can securely attach to the leads of the car's battery. That way the engine alternator will charge the batteries as they are being discharged by the lights. Tie–ing the BattVerter into a vehicle engine will extend the running time on your batteries so much that you may never run out of power. If you don’t require a lot of lights, a Battverter will enable you to use a car as a generator. Use the engine to run the lights through the Battverter as described above during set up and rehearsals. When it comes time to shoot a take, simply shut off the engine and continue to run the lights on the BattVerter alone. Running the vehicle engine between takes charges the batteries so that they will run lights all night. To see how to build a Battverter, use the link below for a more elaborate Battverter system that we built to run four 4' 4 bank Kinos to light a shuttle bus for the upcoming feature "Shuttle" that was shot here in Boston on the Viper. The production stills show you pretty much how we wired it into the shuttle bus. http://www.screenlightandgrip.com/html/hdfilmstrip4lg.html Word of caution: charging batteries generate Hydrogen gas. Do not use a Battverter in charging mode inside a tightly sealed car. Put the Battverter in the trunk, or rig it to the front bumper (as pictured in the “Shuttle” production stills), if you are going to use the engine to charge it while shooting. Guy Holt, ScreenLight & Grip, Rigging Gaffer on “Shuttle”