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AC Generator for Studio packs on location


timberwolf1

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I am aware of the brands for generators: Honda, Generac, Coleman,

etc. What are your working experiences with these generators and

using equipment that may have a microprocessor in it such as a

Speedotron Force 10 mono light? Are the larger 7,500 watt

units "clean power" enough to power a microprocessor safely? What do

you know about using generators on location?

 

Timber Borcherding timberborcherding

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I've not used a generator with any kind of photographic equiptment, but from experience in a former life as a system admin, I'd advise any (relatively) sensative electronics should probably not be pluged directly into a generator, as they have notoriously "dirty" (read inconsitant) power. I've never tried this with photo equiptment, but you might try a UPS system like you'd see on a computer. You'd have even, consistant power, and a few pops after you run out of gas, and goodness knows unexpected things like that _never_ happen on location.

 

Peter

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Our 4000W Generac is a 2 pole 3600Rpm unit driven by a 8Hp 4 cycle Briggs. It is loud; like a lawn mower. The output is a nice sine wave; it has been used to run power supplies that drive my ham radios; and also run my computers. I have used the home generator during blackouts to get on the internet; get email; post on this board; do Photoshop; watch local TV; fire up the microwave; and even run a dinky window AC..One can view the sinewave output with a scope. Overloading a generator will droop the voltage; usually the breaker will then trip....I try to run the generator here every other month; they need usage to prevent the carbs from getting gummed up...<BR><BR><BR>The super quiet small/dinky cute HONDA's are great for swap meets; where the provide small lightweigh portable power; without driving your neighbors nuts. They are super quiet; but are real expensive for the power output<BR><BR>larger Hondas are quiet too.
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The biggest problems I have seen with generators are; too small of wiring to the load. Size of load too big for the generator. Lack of understanding of running loads versus starting loads of AC motors. Poor and illegal grounding of generator. Lack of proper safe way to refuel hot generator. Not enough fuel to keep engine running to do the job. <b>Damage due to unplugging all of the loads from the generator at once; so that the inductive kick from other loads ruins one equipment; if they are tied together thru one circuit or extension cord. </b>
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Great responses; keep going. As for the gummed carbs: I believe that gasoline

becomes shellac at warm temperatures. Therefore it would be best to store dry.

 

A 2000ws Norman studio pack, I am told by experts, draws a 60 amp load when it

peaks. The pack is rated 15 amps, but peaks at 60 amps. This draw is similar to a

short in the line, that is, the capacitors draw the electricity so fast that it is similar to

having a short. This accounts for the 60 amp draw. Now, this draw won't pop the

fuse because it is too brief. Heat has no time to build up. You would need repetitive

pops to heat up the fuse. But what is the effect on the generator? You can't fool the

generator! How much of an over capacity do you need for a 2400ws pack? How

much for a 1200ws pack, 4800ws pack, etc.?

 

Is anyone using a generator for rapid pops, like fashion? What are your experiences?

 

Is there anyway to further quiet the Generac? Is the sine wave truly clean or is it a

square wave?

 

Keep going!

 

Timber Borcherding timberborcherding

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My local HAM radio club has a 4 kW Honda, old but reliable. The little Hondas are nice you nearly could give classic concerts on a electric quitar powered by them. But I suppose you don't need a everyday generator so get something cheaper than Honda. Maybe military surplus? I have a Sachs 2stroke driven Bosch which is damned reliable but of course to small for serious flash setups (750W). I'd suggest to add a plain minimal load to your flash equipment to have the generator runing constantly but I suppose CW PAs are worse than flashes
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  • 3 weeks later...

I talked to the tech at Speedotron regarding generators. This is what he said in a

nutshell:

 

There are two kinds of packs: transformer packs, and transformerless packs.

Transformerless packs are called "capacitor voltage multiplier" units.

 

Transformer packs are the lower end packs like the Speedotron Brownline.

 

Transformer packs do not need a sinewave, but can take the "square wave" generated

by inverters and some generators. "Capacitor voltage multiplier packs" absolutely

need a full sine wave for operation.

 

Therefore, if you are using a battery and inverter combination (no generator), you

should be using "transformer packs".

 

If you are using a generator, be sure it is a sine wave generator and you can use it on

both transformer or transformerless packs.

 

Timber Borcherding timberborcherding

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Most all AC generators that I have used generate a sine wave. There is a rotating rotor on mine at 3600 rpm; which produces the 60 hertz. At light wattage/loads; the frequency is slightly above 60Hz; say by 0.5 to 1 Hz; at full load; the frequency drops to about 59 hz.<BR><BR>The invertor units that produce a square wave are the older invertors such as my tripp lite model PV-100 power invertor; which produces a square wave. These units draw alot of power when not even loaded<BR><BR>Some of the newer more efficient invertors produce a pseudo sine wave; and have little DC input draws at low load. <BR><BR>
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  • 2 weeks later...

Regarding re-buildability:

 

All generators have a operating life. I picked up an opinion of a heavy user, a street

muscian in San Francisco at Pier 39 who puts 8-10 hours on his Honda Generator

Eu3000si.

 

He says that the plastic, smaller EU 1000 and EU 2000 are "discardable generators".

Why? Well, he had one rebuilt, and it was never the same. it came back with variable

Hz, etc. The larger generators of the 3000ws and above are rebuildable in his

opinion.

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  • 3 years later...

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