Brian McGee

I realize that the answer to this will be different for NY vs. Calif., etc., so this is more of general inquiry. In NYC, NY, it's common practice to ground a generator to the nearest hydrant. You're putting blind faith into the network of iron pipes and unknown soil composition(s) to provide a low resistance path for your generator ground. Without taking a reading with a megger, how can you be certain you are successful? I was on a shoot with a boatload of poorly maintained lights, many of which had housing which had become live. Would we have been safer, removing the hydrant ground, thus isolating the supply from the earth?

Ground at the source only, generator ! Grounding at a distro point can defeat the main breaker on generator.

For verification, put one end of your volt meter on a hot leg and the other to the ground rod, It will show line voltage if it is right.

Also, a good ground will show less than 200 ohms to anouther "known Ground" at 6 feet .

None of this is used but this is the real deal:

 

Grip & Lighting Stands - American Grip makes the best Grip Equipment & Lighting Stand Equipment on the planet. Lousy website.. phenomenal equipment!

 

Tungsten Lighting - Mole-Richardson

 

HMI - Well, that's another story.

 

Kinos - Well, Kinos are Kinos...

 

Carts - Noma Fab ... just received three Carts from them.. Phenomenal Carts!!! #1

Regenerators in Dallas Texas sometimes has used generators and distro equipment

www.regenerators.com

Thanks so much to everyone who responded, I really appreciate it.

 

If you fail to balance the generator correctly, what are the negative side effects? Also, when you are striking on or saving the lights, would it be best to do it simultaneously at the source, or turn it off at the generator?

Colleen, I wanted to answer you question a little further:

Lets say you have a 3 phase generator{120-208volt} For this example we will use LitePower's configuration with a Basler or Marathon voltage regulator.

As the engine spins the generator around, it passes each "leg" The leg's are spaced equally in a circle, as it passes the leg that is loaded heavy, the engine has to work hard to produce enough power to satisfy the demand{engine slows down a little}, then it passes a leg that is loaded light it doesn't have to work as much so it passes quickly. This will cause engine speed to vary wildly{Hz or Frequency}. Also , most of our 60,120,and 140kw generators use 2 legs to control voltage. The voltage regulators function is to maintain a constant voltage between phase 1 and phase 2 to our pre-set point of 208 volts. As the leg loaded heavy goes by, the regulator looks at it and says"increase" but when it see's the leg loaded light it say's "decrease". Phase 1 could be as much as 20 volts too high, and phase 2 could be 20 volts low, however measured between them you still get 208 volts, measure line to neutral and it wont be 120 volts. This is a bad thing,however some generators use a three phase voltage regulator{this is the case with our 220KW Generators} with a PMG generator{Perm. magnet generator}. This type of generator is much more forgiving in regard to balancing as each leg is adjusted separately.

Also, use the ballast, not the generator's circuit breaker, and ground properly, especially when using dimmer racks.

I'm a graduate film student at FSU and have acted as BBE and here we balance our genny truck (3 legs) as described above with no issue.

Other practical advice:

1) Stay informed about how many lights are going up and how many amps ( paper amps are fine) they draw.

2) Be aware of when a light or lights are being turned off and will not be used as expected.

3) If you cannot balance the load on all the hot legs with the lights that are being used, you will have to "ghost" a light, which is what we call plugging in an extra light on the necessary leg in order to balance the load and aiming it away from the set into a safe place.

4) You can use an amp meter to make sure the loads are reasonably balanced (no more than ~10 amps of inequality).

5) Attach the ground and neutral legs of the cam lock first and unattached them last.

 

There's a lot more about safety with the genny than balancing the legs, be wary and read up on it, or ask a professor I suppose.

Good advice Kyle, Balance is actually 20% of Total load used, if you have 100 amps on L1 then L2 and L3 need to be 80 to 120 amps each. Ground it correctly.

I'm getting a 35kW Onan Diesel in a month or so (trade-out for some engineering work). It hasn't run in years because of disinterest but it's got very low hours on it. It wouldn't have been mothballed properly, just ignored after the battery went dead. What would you do to bring it back to life other than obviously buy a new battery.

 

Also, who makes the crystal kits for generators? I seen reference to the kits in posts by LA gaffers but don't know where to start looking.

Replace the battery and any connections that have any corrosion at all, especially the battery negative.

Fresh Fuel !

Disconnect the fuel pump actuator so engine WONT start. Change the oil, and fuel filters. Fill fuel filter half way with dexron mercon transmission fluid. Run through several crank cycles to pump up oil through engine and turbo charger and to get dexron into injection pump, this will clean it out.

Now re-connect actuator and crank it up. It will smoke for about 3 minuets or so and then shuld start to run cleaner.

It is also a good idea to inspect inside generator for dirt dobber nests and mice. Look at all rotating parts you can see, especially the fan{inside generator}.

You may also have to prime the fuel pump, Cummins engines have a bleed port for this, others you may need to crack an injector line to get all air and contaminated diesel out.

Woodward and goveners of america sell sync kits but be carefull, if you havent done this before you can easily destroy the engine. I am in Dallas but I can recomend a guy in Van Nuys who can install these units. Hope it goes well !

I see several posts here regarding portable diesel generators for motion picture use. If you have questions you would like to ask a manufacturer of some of these,let's have it.

Unfortunately for me, there is no relation. And you are right that every tool has an application. The added expense of a Honda EU6500is is not necessary if you are not recording sound and using predominantly tungsten light instruements.

 

 

 

In my experience, when you do need to power HMI & Kino ballasts and record clean audio tracks a Honda EU6500is can do the job. It comes down to how you use the generator. If you know how to use it, it is possible to record location audio without picking up generator noise - especially if you use them with a transformer. The Honda EU6500is inverter generator to begin with is much quieter than the older movie blimped Honda EX5500. Part of what makes the new Honda EU6500is so quiet is it's "Eco-Throttle." The Eco-Throttle's microprocessor automatically adjusts the generator's engine speed to produce only the power needed for the applied load. It can do this because the inverter technology of the Honda EU6500is enables it to run at different RPMs and maintain a constant frequency and voltage. Where conventional generators like the Honda EX5500 and ES6500 have to run full speed at a constant 3600 RPM to produce stable 60 hertz (cycle) electricity, a Honda EU6500is only needs to run as fast as required to meet the load demand. Since their engines do not have to run at full speed, and given the fact that an inverter generator generates 20% more power per revolution of the engine, makes the Honda EU series of inverter generators substantially quieter than conventional models.

 

The net result is that the EU6500is operates between 34 to 44 dBA at 50 ft. - half as loud (ten decibels) as the comparable EM7000is and ES6500 generators and comparable to our Crawford 1400A. But you can't park a Crawford right on set and record sound without picking up the generator either. With sound specs this good all you need to record sound without picking up generator noise is a real distro system that will allow you to move the EU6500is off set (like you would a Crawford), minimize line loss over a long cable run, and provide plug-in pockets conveniently close to set. That is where the transformer comes in.

 

My company, ScreenLight & Grip (SL&G), has developed a Gen-set that is designed to provide clean quiet set power from a modified Honda EU6500is. What we do is tap the Honda EU6500is inverter generator as it is designed for 230/240V markets like the UK, EU, Australia, & India (to name just a few.) By doing so, we gain access to the full 7650 Watt power capacity designed into the generator for these 230/240V markets, but not available in generators manufactured for 120V Markets like the US. We then use a proprietary step-down transformer/distro we have developed to convert the full 240V power into a single 60A/120V circuit (7500Watts) capable of powering large lights. And, where PWM inverter generators, like the Honda EU6500is, generate a nearly pure power waveform, our modified Honda EU6500is is capable of reliably powering more lights than has been possible before. Finally, to record sync sound without picking up any generator noise, all you need to do is add 100' - 150' of heavy duty 250V twist-lock extension cable between the generator and our Full Power Transformer/Distro. This is usually enough cable to place the generator around the corner of a building, or to run it out of a van or truck - which is usually all the additional blimping you need with these generators. The heavy-duty 250V twist-lock cable eliminates multiple long cable runs to the generator and minimizes line-loss; as well as, eliminates the voltage drop you would have using standard electrical cords.

 

A Distro System consisting of a 60A Full Power Transformer/Distro, 2-60A GPC (Bates) Splitters, 2-60A Woodhead Box distributes power from a modified Honda EU6500is. Even though the generator is 100' away to reduce noise, plug-in points remain conveniently close to set.

 

To assure full line level (120V) on set, our 60A Full Power Transformer/Distro is designed to compensate for the slight line loss you will have over an extended cable run. That is, it is designed to slightly boost the voltage on the load side (secondary) so that if you were to feed the supply side (primary) of the transformer 240 volts from the generator, 127 volts would come out on the secondary side where you plug in the lights. This slight boost enables you to place the generator further from set where you won't hear it, yet assure that the supply voltage on set does not drop too low. Our 60A Full Power Transformer/Distro is equipped with a 60A Bates and three 20 A Edison circuits so that you have plug-in pockets conveniently on set.

 

60A GPC (Bates) Splitters and Woodhead Box.

 

Our new 60A Full Power Transformer/Distro offers a number of other benefits as well. Without our Transformer/Distro you can never fully utilize the full power of the 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 factory installed power outlet panel of a Honda EU6500is, you quickly reach a point where you can't power an additional 1200W HMI because there is not 11.5 amps (w/ a PFC ballast) available on either one of the factory installed 20A outlets/leg of the generator. With our Full Power Transformer/Distro you can still add that 1200W HMI because the Transformer/Distro not only accesses more power (7500 Watts) through a higher rated circuit (60 Amps), but it also splits the load evenly over the two legs (5.75A/leg) of the generator. The end result is that the generator is capable of handling a larger load more easily because it is a perfectly balanced load.

 

60A Woodhead Box running Power-to-Light PFC 800W ballast (left) and PFC 1200W ballast (right.)

 

Another benefit to using our Transformer/Distro is that it greatly simplifies set electrics by splitting the load of what ever you plug into it automatically. This means you no longer have to carefully balance the load over the generator's two 20A/120 circuits/legs as you plug in lights because the Transfomer/Distro does it for you. With our modified Honda EU6500is you simply plug in lights until the load wattage displayed on the generator's iMonitor reaches 7500 Watts. Now that you are able to fully utilize the generator's available power, you are able to power larger lights, or more smaller lights, than you could without a transformer/distro. For more details on the use of transformers for set power, I suggest you read the article I wrote for our company newsletter (mentioned above) on the use of portable generators in motion picture production. Use this link - www.screenlightandgrip.com/html/emailnewsletter_generators.html for more information about using inverter generators with transformers for motion picture lighting.

 

Guy Holt, Gaffer, ScreenLight & Grip , Boston

Guy, Thanks for the detailed response,over the top! In short if you want to be a professional, use professional equipment, not a toy from home depot.