Movie Quiet® Generators – Technical Information

1. “Green” LitePOWER Generators

At Burrell Enterprises, we have been “GREEN” longer than it has been popular. Anyone can paint a generator green and call it environmentally friendly. We go way beyond that. Our LitePOWER® generators and our manufacturing processes are the epitome of being friendly to our environment. We have three environmental considerations when we design and manufacture our LitePOWER® equipment; direct impact from emissions, conservation of resources and recycling.

Direct Impact On The Environment From Emissions

Exhaust emissions, crankcase vent emissions and fuel leakage have a direct impact on the environment. Manufacturing processes can also have a direct impact:

  • We have no direct control of the exhaust emissions. The engine manufacturers build our engines to the latest available technology as dictated by the EPA. We commissioned a study comparing our old LitePOWER® 200kw with the new LitePOWER® 220kw. In a typical year of operation we saved 3.5 metric tonnes of greenhouse gases. This number will be far greater when compared to older equipment.
  • This performance is enhanced by our enclosure and packaging. In addition to operating the engine at the proper temperature (in all ambient temperatures) we create less parasitic horsepower loss by replacing the inefficient propeller-cooling fan with a centrifugal blower. The propeller fan, as supplied for our 220kw draws 43 horsepower from the engine at all times. Competitors replace that fan with one that requires even more power. We replace it with our centrifugal blower, powered by a 7.5 horsepower motor, which operates at about 4 horsepower. This is a continuous savings of 39 horsepower, a lifetime benefit. LitePOWER® generators deliver more power with fewer emissions and less fuel usage per kw.
  • All LitePOWER® generators built after June of 2007 are rated to use biodiesel fuel. Using biodiesel fuel greatly reduces exhaust emissions, is less toxic and is a renewable resource. Some LitePOWER® generators have been using biodiesel for the last 8 years with no side effects (see Biodiesel Usage in LitePOWER Generators for more information).
  • Diesel engines vent crankcase gases to the atmosphere. Crankcase emissions, or blow-by is the result of high-pressure gases and oils escaping around the piston rings into the crankcase then, via a vent, into the atmosphere. Blow-by is an oily mist comprised of aerosol and larger oil particles. All LitePOWER® generators are now fitted with lifetime filters that trap these particles and return them to the oil pan eliminating airborne aerosols and oil drip.
  • Diesel fuel spills are very common with generators mounted on trailers. This occurs because diesel fuel can thermally expand 5 percent. Most generator/trailer packages do not account for this in the design. As a result these packages spill fuel in the warm weather if they are “accidentally” filled all the way to the top. On a 160-gallon tank this can be as much as 8 gallons! This is amazing and totally unacceptable. Every LitePOWER® Generator on a LitePOWER® Trailer has either a separate expansion tank or a generous amount of air space in the top of the tank for expansion. Our LitePOWER® Generators will not leak fuel due to thermal expansion. Fill them to the top without worry.
  • LitePOWER® products, including generators and trailers, are painted with a powder coat paint process. Paint, in powder form, is electrostatically applied then baked in an oven. Every part and assembly is coated on both sides before final assembly begins. We are the only manufacturer in our industry to use this process. For the environment, powder coatings offer many benefits. Solvents are not used in the powder coating process; no damaging, volatile vapors are released during application, and powder overspray can be reclaimed for subsequent use. Powder Coatings are environmentally friendly and there is no waste.

Conservation Of Resources And Recycling

  • LitePOWER®. Our name says it all. We do more with less. Our LitePOWER® generators are engineered to weigh less and take up less space. How does this affect the environment? Our LitePOWER® generators weigh as much as 4,000 pounds less than our competitors. We use less of our natural resources to produce them. Logistically we have less infrastructure usage because we are moving less material. Our customers have less weight to haul and can use smaller, more fuel-efficient vehicles. This is a lifetime benefit and it pays off every time the generator is moved.
  • LitePOWER® Generators are designed to last 25 years. We have been building them for 16 years and all but a few that were wrecked are still in service. When the time comes to permanently take a LitePOWER® generator out of service 98% (by weight) of the generator and trailer can be recycled.

Summary

There is no specific definition of a “GREEN” generator. We have no rules or guidelines to follow but we have a responsible attitude about our LitePOWER® products’ impact on the environment. We take this responsibility seriously and are proud of the results.


2. Biodiesel Usage in LitePOWER Generators

Every LitePOWER generator delivered after June 2007 can be fueled with biodiesel fuel without any modification. All other LitePOWER generators can be fueled with biodiesel with one minor modification that can be done at a nominal charge. We have experienced LitePOWER generators running on biodiesel fuel for the last 8 years with no negative side effects.

Biodiesel has many benefits and is becoming very popular, especially in the motion picture and entertainment industries. Our purpose here is not to “sell” anybody on the benefits of biodiesel but to inform our customers of the proper use of this fuel.

We use Cummins diesel engines in our LitePOWER generators and most of the information we have gathered about biodiesel is from their engineering department. Following are several bulletins and articles we have gathered while learning about the use of biodiesel that we would like to share with you.

If you are using biodiesel and have experiences you would like to share with us please let us know. Anything new that we learn will be added to our database and added herein.

List of Articles and Bulletins


3. Knot Code for Feeder Cable

How do you tell the phases on feeder cable when it isn’t color-coded or when you are working in poor lighting conditions? Most Cam Loc 4/0 feeder cable is not color coded, the connectors are black. All lug type feeder cables are not color coded unless someone has put colored tape on them. The problem is that the tape falls off or gets so dirty you can’t tell the color.

Here’s how it’s done. Tie a sash cord on either end of the cable. Tie knots in the cord as follows:

  • Black Leg – Two knots on one side.
  • Red Leg – One knot on one side.
  • Blue Leg – No knots.
  • Neutral – One knot on each side of sash cord.
  • Ground – Two knots on each side of sash cord.

Please note that I have not identified the phases as Leg 1, Leg 2 or Leg 3. This is because there are no standards and the phase colors is different from market to market!


4. Phase Color Codes

Because there are no written standards for color-coding of the phases we have to ask the customer their preference. On all LitePOWER generators the legs are clearly labeled as Leg 1, Leg 2 or Leg 3.

If the customer has no preference we use the following colors for our LitePOWER generators. This seems to be standard in the East and Midwest. We’ve noticed that these companies use the same color-code in their distribution boxes. Indu Electric, Union Electric, Mole Richardson, Crouse Hinds, and Lex Products.

  • Leg 1 – Black
  • Leg 2 – Red
  • Leg 3 – Blue

In California, especially the LA market, the color code that is requested is as follows.

  • Leg 1 – Red
  • Leg 2 – Blue
  • Leg 3 – Black

And here is what has been requested from British Colombia.

  • Leg 1 – Red
  • Leg 2 – Black
  • Leg 3 – Blue

Obviously, it’s important to be able to identify the different legs for balancing loads. It is especially important to know the legs when paralleling generators together. The phase relationship of each generator must be matched. If not, it could ruin your day!


5. HMI Flicker

To fully understand HMI flicker you must first realize two of the basics.

The light source, HMI, is a strobe light. When using magnetic ballast, the globe is ignited 120 times per second with 60hz current.

The camera, at 24 frames per second with a 180 degree shutter, has an exposure time of 1/48th of a second.

This yields 2.5 flashes per exposure, an uneven number, and this is the problem. Imagine, better yet, draw a sine wave on a piece of paper. Make the sine wave with about three up humps and three down humps. Draw a straight line through the center. Each time the line intersects the sine wave there is 0 voltage. At the peak of every hump is the maximum voltage (typically 120V). One cycle lasts from the zero voltage point through one up hump, back to zero, through the down hump and then back to zero voltage.

The HMI ignites at maximum voltage and then decays at 0 voltage, over and over. We perceive this as continues light but obviously it is not. The film is exposed by 2 1/2 of these flashes.

Take a separate piece of paper and cut a hole in that is 2 and 1/2 flashes (humps) long. Slide it slowly along the sine wave you have drawn and try to imagine the variations in light level that will be produced as you expose different parts of the sine waves. This variation in light level is called HMI flicker. The faster the window is moved across the sine wave the more noticeable the flicker is.

Our challange is to keep the window from moving across the sine wave, or at least make it move so slowly that the change in exposure is not perceptable. This is done by controlling the camera and generator speed very precisely.

Cameras, because of independant sound recording requirements, operate at an accuracy or 50 parts per million or better. They are locked in at 24 FPS and are not a problem.

Generators are the weak link in this senario. We must control the frequency (engine rpm) to within plus and minus 2 tenths of a cycle from 60 HZ. (59.8 to 60.2) We do this with “precision speed controllers” but it requires everything in the system to be stable and operating perfectly. That is why generators are monitored so closely on sets.


6. Paralleling

PARALLELING or LOAD SHARING is where two or more generators are connected together so that they operate as one. The most common application is our national power grid that is made up of hundreds of individual generators all operating as one. The most common use in our industry is where 2 generators are connected to each to provide total redundancy for important projects like live events or live broadcasts. In this example each would be operating at no more than 50% of its capacity. Should one of the generators fail it would be knocked OFF LINE and the remaining generator would take up the load seamlessly.

To parallel two generators together they are first wired to a common buss, which is connected to the load. At this point both generators are separated from the common buss with an electrical switching devise like a breaker or contactor. The first generator is started and is connected to the buss or put ON LINE. At this point it is generally good to have a load on the buss. The second generator is then started and adjusted (manually or via electronics) so that the voltage, frequency and phase relationship are exactly the same as the first generator. The moment that all three are matched the second generator is put ON LINE. This connection can be manual or automatic, depending on the equipment you are using. From that point on the two sources will act as one. The voltage, frequency and phase will be locked together as if the two had a common crankshaft.

On LitePOWER generators the standard output panels can function as the common buss. LitePOWER generators that are equipped with the paralleling option come with a vacuum contactor to connect to the common buss. When purchasing a LitePOWER generator you can choose from any of the numerous electronic operating systems that are available.