Gennies

Walter Graff · January 7, 2009

Just bought a 3500 watt genny as a backup for my home. We loose power on occasion due to ice storms, etc. Of course it will not run the whole house, but enough of what I need when the power is out. And if I need it for location, I have it. I remember just a few years back such gennies where in the range of 1800. I got it new for $479. Can't beat that. Just set up a bypass on my breaker box and ready to switch over if the power goes out.

Adrian Sierkowski · January 7, 2009

I have seen some 1800W ones for around $200 off of walmart.com and I think sears.

HomeDepots smallest was also an 1800 I think, but was priced around $250.

Any leads on which genny is the quietest for sync? I'm talking on put-puts here.

Steve London · January 7, 2009

I have seen some 1800W ones for around $200 off of walmart.com and I think sears.
HomeDepots smallest was also an 1800 I think, but was priced around $250.

Any leads on which genny is the quietest for sync? I'm talking on put-puts here.

The Honda EU series. They run from 1000 to 6500 Watts use inverters so produce clean sine wave AC for electronics and are quiet - 49 -58 db(A)

But putting one a little distance from the set, around the corner of a building and tenting with some furnies and you can do pretty well on noise with any putt putt.

Walter Graff · January 7, 2009

The Honda EU series. They run from 1000 to 6500 Watts use inverters so produce clean sine wave AC for electronics and are quiet - 49 -58 db(A)

But putting one a little distance from the set, around the corner of a building and tenting with some furnies and you can do pretty well on noise with any putt putt.

Or use a transient voltage surge suppressor with any non locked genny and get pure ac.

Michael LaVoie · January 16, 2009

Does anyone custom baffle put put genies anymore or modify them to run crystal sync? Seems like a thing of the past.

David Rakoczy · January 16, 2009

Having lived off my Genny for 7-10 days.. TWICE.. due to Hurricane Ivan and Hurricane Dennis, I can tell you my 5500 went through about 10 gallons a day running a window air conditioner unit, refrigerator, lamps, TV, DVDs and stereo..... it all depends on how many amps you are pulling... They are great to have on hand for home emergencies as well as using for night exteriors ;)

Matthew Buick · January 16, 2009

Sort of off-topic but I'll say it anyway. On boxing day we had an awful power cut in my area, and since we've been suviving on the power generated by a white 'Aggreco' box about 8ft x 10ft x 6ft. Anyway, this is a huge area, proabaly around 250 houses! It's amazing how efficient it is, and the only noise you hear is a light diesel thrum!

freddie bonfanti · January 16, 2009

Sort of off-topic but I'll say it anyway. On boxing day we had an awful power cut in my area, and since we've been suviving on the power generated by a white 'Aggreco' box about 8ft x 10ft x 6ft. Anyway, this is a huge area, proabaly around 250 houses! It's amazing how efficient it is, and the only noise you hear is a light diesel thrum!

id love to know how much diesel was used in total...ive seen an Aggreko 500Kw gennie once, coolest thing ever

Michael Collier · January 16, 2009

Not to hijack the thread but has anyone used a propane genny?

I have been seeing small ones at Fred Meyers lately and I think they are new. The one I saw was 3500 watt and maybe 300-400 bucks. I don't know much about them but it seems like they would be super quiet, and they might be xstall sync.

Or more accurately I think they might not have an alternator, but rather a generator (DC) that goes to a high-watt inverter. At least thats what it looked like, it had 12v full rated load out, and it didn't seem like a transformer/rectifier assembly (why have 12v out unless thats what the generator produces natively) If it is native 12v then the 120v AC lines would almost certainly be xstal clocked, and work with magnetic ballasts?

Walter Graff · January 17, 2009

Not to hijack the thread but has anyone used a propane genny?

I have been seeing small ones at Fred Meyers lately and I think they are new. The one I saw was 3500 watt and maybe 300-400 bucks. I don't know much about them but it seems like they would be super quiet, and they might be xstall sync.

Or more accurately I think they might not have an alternator, but rather a generator (DC) that goes to a high-watt inverter. At least thats what it looked like, it had 12v full rated load out, and it didn't seem like a transformer/rectifier assembly (why have 12v out unless thats what the generator produces natively) If it is native 12v then the 120v AC lines would almost certainly be xstal clocked, and work with magnetic ballasts?

I've used propane gennys. Another "green" industry exploitation. Only difference is you can't spill gas on the generator if you are stupid enough to fill it running or without proper funnels etc. Outside of that it runs exactly the same way in terms of efficiency.

Walter Graff · January 17, 2009

id love to know how much diesel was used in total...ive seen an Aggreko 500Kw gennie once, coolest thing ever

At that size with a moderate load and that size they use around 40 gallons an hour.

Michael Collier · January 17, 2009

I've used propane gennys. Another "green" industry exploitation. Only difference is you can't spill gas on the generator if you are stupid enough to fill it running or without proper funnels etc. Outside of that it runs exactly the same way in terms of efficiency.

What about the noise? Are they quieter than petrol or deisel generators?

Walter Graff · January 17, 2009

What about the noise? Are they quieter than petrol or deisel generators?

No. Not because of the fuel as much as the manufacture. A Honda 5500 gas gen is 20 db quieter than the propane ones sold by other manufacturers. Overall, they al make noise and the bigger they are the quiter the muffler system due to alowable air expression and supression systems used.

Hal Smith · January 17, 2009

....Just set up a bypass on my breaker box and ready to switch over if the power goes out.

Walter,

Hopefully there is absolutely no way your generator tie-in can send power back out on the commercial powerlines no matter what position any switch/breaker/plug is in? National Electrical Code (NEC) requires that of any emergency generator tie-in. Also a requirement is that emergency power and commercial power can only co-existent in an automatic or manual changeover cabinet.

In Boston I designed a manually operated NEC legal emergency generator interconnect by bringing the commercial power out to a large, high current receptacle immediately after the primary disconnect breaker. I then had an SO cable cord with a plug matching the receptacle which went to the panel box with the branch breakers in it. There was an additional primary disconnect breaker and receptacle that went to the generator's output. The procedure for generator power required manually unplugging the corded plug from the commercial receptacle and into the emergency one. That met both the code requirement for the physical separation of emergency and commercial power wiring as well as the requirement that there was no possible way of feeding emergency power out onto the commercial powerlines. The extremely strict and by-the-book City of Woburn electrical inspection department signed off on that installation.

Walter Graff · January 17, 2009

It's got a one way interconnect as required.

Guy Holt · April 28, 2009

Does anyone custom baffle put put genies anymore or modify them to run crystal sync? Seems like a thing of the past.

I run a rental house in Boston by the name of ScreenLight and Grip and we rent and sell small portable generators for film production. It is no longer necessary to blimp or crystal modify generators. A lot of the conventional wisdom regarding portable generators went out the window with the recent development of inverter generators and power factor correction (PFC) in smaller (575-1200W) HMI ballasts. It is now possible to get 7500W of clean stable power in a single 120V circuit from a portable generator. And, when you add up the incremental savings in power to be gained by using PFC HMI ballasts, add to it the energy efficiency of light sources like LEDs and Kino Flos, and combine it with the increased light sensitivity of film stocks and digital imaging systems, you have what, I would argue, amounts to a paradigm shift in lighting with portable generators.

In the past, it was not possible to reliably operate more than a couple of 1200w HMIs on a portable generator even with crystal govenors. The primary factors limiting the use of HMIs on portable generators has been their inefficient use of power and the harmonic noise they throw back into the power stream. The adverse effects of the harmonic distortion generated by HMI ballasts (see power waveform below left), can take the form of overheating and failing production equipment, circuit breaker trips, overheating of the neutral wire, and instability of the generator voltage and frequency. Severe harmonic noise can also damage HD digital cinema production equipment, create ground loops, and create radio frequency (RF) interference.

If one knows how, it is possible to take advantage of recent technological advances in HMI ballast design and power generation, to create clean stable set power (like that in the power waveform above right) that is capable of reliably operating larger lights (HMIs up to 6kw or Quartz lights up to 5kw), or more smaller lights, off of portable gas generators than has ever been possible before.

For example, on a recent independent short shot on the Red, I used a modified Honda EU6500is Generator to power a lighting package that consisted of a 2.5kw, 1200, & 800 HMI Pars, a couple of Kino Flo ParaBeam 400s, a couple of ParaBeam 200s, and a Flat Head 80. Given the light sensitivity of the Red Camera, this was all the light we needed to light a large night exterior.

But, given the wide variety of generators manufactured, it is important to understand the benefits and drawbacks to each when it comes to their use in motion picture production. Especially, given that the increasing use of personal computers and microprocessor-controlled recording equipment in HD production has created an unprecedented demand for clean, reliable power on set at a time when the trend in lighting is toward light sources that can generate dirty power. For this reason, I have tried to compile a comprehensive survey of the prevalent lighting and portable power generation equipment. Test how well they work together and make the results available to the production community. Where Harry Box, the author of the Set Lighting Technician’s Handbook is interested in incorporating this material in the 4th edition of the handbook I am making it available for peer review first.

I feel the need to make this material available prior to publication in the handbook because specific details of the inner workings of the latest portable power generation equipment is in short supply and harmonic noise has only recently become an issue. Why is harmonic distortion suddenly an issue in motion picture production? Because, the power generation and electrical distribution systems developed for motion picture production were never designed to deal with the abundance of non-linear loads like the electronic HMI and Fluorescent lighting ballasts so prevalent in production today. It’s a problem that has only recently begun because of the increasing use of these types of non-linear lighting loads. The problem is being further compounded by the increasing prevalence on set of sophisticated electronic production equipment like computers, hard drives and HD monitors which are themselves sources of harmonic distortion.

In the past, attention was given to generator features such as automatic voltage regulation and speed regulation. But, given the rise in production problems associated with harmonic noise, an increasingly more important feature today is the quality of the generated power waveform and how well it interacts with today's light sources. For that reason, I did a series of tests that have resulted in oscilloscope shots of the power waveforms of different light sources on different portable generators. I have attempted to interpreted the artifacts of harmonic distortion exhibited in these power waveforms, but where this is a relatively new issue, I welcome the input of other film/video production professionals so that the material can be as complete as possible for the handbook.

To see the results of my tests, use the link below to our website where I have posted my analysis of the compatibility of the latest lighting and portable power generation technology

www.screenlightandgrip.com/html/emailnewsletter_generators.html

I welcome any and all feed back.

- Guy Holt, Gaffer, ScreenLight & Grip, Boston

JD Hartman · April 30, 2009

Not to hijack the thread but has anyone used a propane genny?

I have been seeing small ones at Fred Meyers lately and I think they are new. The one I saw was 3500 watt and maybe 300-400 bucks. I don't know much about them but it seems like they would be super quiet, and they might be xstall sync.

Or more accurately I think they might not have an alternator, but rather a generator (DC) that goes to a high-watt inverter. At least thats what it looked like, it had 12v full rated load out, and it didn't seem like a transformer/rectifier assembly (why have 12v out unless thats what the generator produces natively) If it is native 12v then the 120v AC lines would almost certainly be xstal clocked, and work with magnetic ballasts?

Not quiter as already stated, but cleaner. Cleaner in a way that a propane or natural gas operated generator will accumulate less wear on the engine components. Onan has always advocated NG for its installed backup generators. We just set up a used 1958/59 Onan 25KW generator, run by a Ford straight 6 industrial engine. Over 500 hours on the clock and the factory hone marks are still visible on the cylinder walls. You might want to look at the Onan inverter generators as well.