DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Photon Management (https://www.dvinfo.net/forum/photon-management/)
-   -   Powering the Outdoors- What to use? (https://www.dvinfo.net/forum/photon-management/57924-powering-outdoors-what-use.html)

Drew Meinecke January 9th, 2006 09:44 PM

Powering the Outdoors- What to use?
 
What is a good solution for powering outdoor scenes for lights and such?

Walter Graff January 9th, 2006 11:03 PM

Generator is easiest. Tough and dangerous to try to run extension cords over 150 feet.

Eric Elliott January 10th, 2006 12:52 AM

Car headlights can be surprisingly effective, particularly if you use gels, diffusers and reflectors wisely. Make sure you don't run your batteries dead, though.

You can also get inverters that will turn your car's 12volt DC power into 120volt AC and then you can use regular lights. But, again, this'll suck juice out of your batteries at an alarming rate.

But for situations where you need lots of light for a long while, nothing beats a good generator. The thing with generators is the problem. The best thing to do is build a sound box to fit over the generator and pile moving blankets over it to help further deaden the noise. If you can get a propane conversion kit, that will make the generator a lot quieter but you will lose some power.

Andy Graham January 10th, 2006 01:52 AM

I shot some scenes in woodlands around 300 feet from a mains source and one scene nowhere near a mains source, we couldn't use a generator as we were using the sound that was being recorded (no ADR). we used three methods
1)As Eric said car headlights do work well but not so good for lighting a larger area
2)we hired 600 watt battery powerd lights
3)we also hired 400 feet of heavy duty cables with the waterproof conectors and the emergency trip plug.

I'm not sure if the battery powerd lights were a custom design by the lighting co electrician or if they came that way, best idea is to ask your local lighting co if they have them. During shooting they only last 3 hours so only use them on a take. They also get progressivly warmer in colour temp as they die.

Just my 2 cents =)

Walter Graff January 10th, 2006 07:15 AM

"You can also get inverters that will turn your car's 12volt DC power into 120volt AC and then you can use regular lights. But, again, this'll suck juice out of your batteries at an alarming rate."

AND ARE DANGEROUS TO USE.

Bill Ball January 10th, 2006 09:36 AM

I am curious as to the maximum reccomended inverter load for a typical car. The car can be running in my case and I am looking at the inverters that connect directly to the battery/ground. I see ads for inverters up to 1500 watts load and above and I am thinking there must be some limit before you damage your car.

Walter what are some of the major dangers, other than frying yourself?

Andy Graham January 10th, 2006 09:55 AM

I have to agree with Walter I personaly would never use power inverters off cars, there are too many things that could go wrong.

There is danger from electric shock,

you could run down your car battery and be stuck in the middle of nowhere,

It could blow all the fuses in your car

And worse case it could go on fire.

Now im no expert of course but these are the reasons I never used one. Best stick with the genny, Heavy duty cables or battery lights

Andy.

Walter Graff January 10th, 2006 10:55 AM

"I am curious as to the maximum reccomended inverter load for a typical car. The car can be running in my case and I am looking at the inverters that connect directly to the battery/ground. I see ads for inverters up to 1500 watts load and above and I am thinking there must be some limit before you damage your car."

How about your car on fire, your alternator smoking and burning out, or your battery explodes. Seen all three happen with idiots that think electricity comes from the Gods and that you could power your house from your car.

A 1500 amp inverter requires cable to the battery that are at minimum #2AWG, that's the same size as the red cable on your battery but it is not that simple. Most common car alternators return about 70-80 amps of power to your battery. Run a 1000 watt fixture off a 110 volt house outlet (US electric) and you draw about 8.3 amps. Now draw that same current off a car electrical system and your battery needs to generate a continuos 83 amps. Watch your car lights dim, your volt meter drop to 9 volts, and the cars will actually idle at a lower RPM because of the energy you are sucking out of the car. After about five minutes your alternator becomes super hot. After 15 the battery cable in the car become too hot to touch. Using a regular car battery with an inverter will decrease it's life 100 fold. Only deep cycle marine batteries should be used with inverters over 500 watts. Alone a typical 150 amp/hour non deep cycle car battery will run a 1000 watt light for a little over an hour.

Very simply inverters over 300 watts are DANGEROUS!!! AND NO INVERTER OVER 300 WATTS SHOULD EVER BE CONNECTED TO A CAR BATTERY THAT IS HOOKED UP TO YOUR ELECTRICAL SYSTEM WITH THE CAR RUNNING!!

Bill Ball January 10th, 2006 11:10 AM

Thanks for the info on inverters. I'm not a risk taker so I'll look at other solutions.

John Hartney January 10th, 2006 02:03 PM

Plus most inverters put out a square wave, which can damage delicate lighting instruments and their ballasts. You're much better off with a quiet generator set behind a sound screen. Keep your main stingers at 10gauge and you won't have any problems. I use:

Yamaha Inverter YG2800i

Less noise, light weight and clean output...power anything with microcomputers or sophisticated electronics.

* Inverter System with Pulse Width Modulation - Industry-leading system that produces higher-quality and cleaner electricity. Results in pure sine wave as clean or cleaner than commercial power and can operate products with built in microcomputers.
* “Economy Control” electrical governor - Engine speed matches electrical needs which improves fuel economy and reduces noise.
* Sixteen-pole Alternator, Twenty-four Coil Stator - Eliminates conventional two pole rotating field & massive stator for reduced weight, compact design and an exceptional power output to weight ratio.
* Cast iron cylinder lining - Provides optimal heat dissapation, consistent performance during continuous use and long engine life.
* Oil Watch Warning System - Automatically shuts off before oil level is low and cannot be re-started until oil is added. Prevents engine damage and costly repairs while enhancing long-term durability.
* Specially designed muffler - Offers a compact design, reduced weight and noise.
* USFS-approved Spark Arrestor - Offers quiet operation and keeps sparks from exiting exhaust system, reducing chance of fires caused by an errant spark.
* AC Non-fuse Thermal Breaker - Protects AC circuit in case of an overload for added durability and peace of mind.
* DC output - Provides both AC and DC output and enables battery charging.

Eric Elliott January 10th, 2006 04:08 PM

Walter, for idiots, even using a pencil is dangerous. Everything you've said about using an inverter on a car is true but for someone who knows what they're doing it's a viable option. My field vehicle is equipped with a 600w inverter (and two batteries - one deep-cycle for the inverter) that has done me very good service from time to time. I had it installed by qualified mechanics (didn't try to do it myself) and I never use it with the engine running. (Automobile alternators aren't designed for it.) In fact, I couldn't if I wanted to: The switch that enables the inverter also isolates the deep-cycle. Besides, if I wasn't concerned with noise, I'd just use the generator.

That said, one of the quickest roads to disaster is fiddling around with any electrical system when you don't know what you're doing. Fools abound. From your post, you must have run into a lot of them.

Sean McHenry January 10th, 2006 10:46 PM

I agree with Eric. If you have common sense and can do addition, you should be good to go. The common sense thing gets most people at some time, including me.

I have used simple 150W daylight (almost) flourescent worklights off a 250W inverter in the middle of nowhere. I also powered a household strobe off said inverter to simulate a police car for a shoot. Couldn't find a cheap rotating police light in time.

The pencil thing reminds me about airport security. I have said for years (going way OT here) You could hold a plane hostage with a sharp pencil at someones throat. They going to ban pencils next? What about toothpicks? I sharp toothpick can puncture a juglar too.

Anyway, be careful, know your car and your inverters as well as what your lighting pulls and you should be OK. On the other hand, if it all burns up, you were warned.

Sean : )

Marcus Marchesseault January 11th, 2006 12:52 AM

I strongly disagree with much of what has been said about inverters and I am going to go into this, but I don't want to start an arguement. Please don't take this as flames as I generally believe in the spirit of what has been said, but I think the facts and the end result is wrong: "Thanks for the info on inverters. I'm not a risk taker so I'll look at other solutions."

Most recent inverters are not square wave these days. They supply power that even fluorescent light ballasts can happily consume.

A power inverter will not make your car's gas tank explode. This seems implied by all the fire warnings. Yes, you must know the allowable load of all devices on any circuit. Don't run a 5K tungsten on a household circuit and don't run a 2K on a car. I am not an engineer, but it is easy to find the amperage of vehicle alternators. My pickup has a 95Amp alternator. That's 95 times about 13.8Volts (cars are actually over 12V) which is 1311 Watts. The car itself needs many watts to run, but there are plenty left over for an inverter. Playing it safe, I like to stay at about half the capacity of most circuits if the load is going to be continuous. I don't know about you all, but I can do a lot with 600Watts of fluorescent light!

I ran my household refrigerator (600W) for hours off my 1000W (1200W peak) inverter when there was a power outage. Over a year later, my truck and refrigerator are just fine. My truck was at idle and never stalled or made smoke.

HERE IS HOW YOU USE AN INVERTER TO POWER LIGHTS:

1. Learn about your vehicle and battery's capabilities. Many compact cars have insufficient alternators for their own needs, nevermind the loads of an inverter. A Geo Metro with a tiny alternator and a miniscule battery will not suffice.

2. Get a powerful inverter with stepped sinewave or pure sinewave output. These make power most like that coming from the grid. Don't mix the two together. Plug any devices that are electrically connected to each other on similar power. For instance, it might be a good idea to power both a computer's CPU and monitor from the same source since they have a metal wire connection between them. It is probably best to keep things homogenous, even though it likely wouldn't cause a fire. My best guess would be a ground fault that would cause noise in the power and maybe voltage drops.

3. Get a GFCI (Ground Fault Circuit Interrupter) protected extension cord or a stand-alone protector that goes in between the inverter and cord.

4. With the vehicle running, connect it's terminals directly to the battery and not to the cigarette lighter. High-power inverters will tell you this in the instructions. If your inverter does not have a fuse, build one inline with it's positive (red) cable.

5. Keep the inverter away from water and don't short it's cables.

6. Don't overload the inverter. Most devices only work continuously at half to 3/4 of their full load. My inverter has a chart of the run times at various loads.

7. Don't overload the vehicle's power system. If you are running 600Watts on the inverter, don't think you can then turn on the headlights to get extra light.

8. If the car complains in any way, stop. You might have a vehicle with an insufficient alternator and battery for even it's own needs.

9. If you can't use the car, or want peace and quiet, use a deep-cycle Marine battery. Batteries are rated in AmpHours, but they can't utilize full power for a whole hour. They die faster if they are discharged quickly. If they are discharged gently, they can put out about twice the total power as if they were drained quickly.

10. Turn on loads (lights) one at a time to keep from causing a huge spike in the power draw on the inverter. Fluorescent lights and most electric motors have a higher initial draw.

Here is how I did it on Waikiki Beach with no available AC:

I have two 55AmpHour deep-cycle marine batteries. My batteries have AGM (absorbent glass matt) construction which means they do not have free-flowing acid electrolyte. They can also be run from any angle, even upside-down. I got a charger specifically for AGM batteries that does an excellent job of safely charging as well as keeping them topped-off.

With a few hundred watts of a mix of both 3200K and 5000K fluorescent bulbs and some clamp-lamps, we moved everything out onto the beach as the sun went down. I had everything in a garden wagon to keep it in one nice package. A plastic garbage bag served as backup rain protection. We then set up the light stands and clamped on the lights. With stingers going to everything, I connected the inverter with it's GFCI up to the first battery and turned it on.

Next, we shot several angles of a pivotal scene in our short movie. This is the important part.

I changed the battery after about 5 hours because 200W of draw is a challenge for even a big battery. The FX1 we shot with had no trouble with this light level. I don't think we even used any gain.

At the end, we packed up the wagon and went home (at 2:00AM). On both nights of shooting, the lights were faster to set up than the mics.

ONE NOTE OF CAUTION:

Don't bridge the gap between the positive and negative terminals of a battery. If you let a light stand slip or you fumble around with the cable and cause a short, a big lead-acid battery can put off a huge amount of power in a short period of time. The power draw can be so fast that the shorted cables or other piece of metal can melt. If you short with a piece of steel, it can heat up to the melting point and weld itself in place. DON'T CAUSE A SHORT WITH A BATTERY! There is no failsafe to prevent this but care and common sense. Always use a fused circuit and cover metal contacts with electrical tape or, better yet, heat shrink tubing.

Also, common sense with battery-generated AC or grid AC still applies. Don't be stupid and run extension cords through water. Turn off the power if it rains.

Keep a fire extinguisher handy wherever you use power. Keep one (or more) in the kitchen, the garage, and your set.

Andy Graham January 11th, 2006 06:12 AM

Quote:

Originally Posted by Drew Meinecke
What is a good solution for powering outdoor scenes for lights and such?

Well I'm not one to argue with people who clearly have more knowlage of the subject.

Back to the origional topic. Drew you could look into getting a caravan generator, they are designed to be quiet because lets face it nobody wants to hear a horrible generator when they are staying in their caravan.

My brother got one and I imediately saw its potetial for powering lights and other field equipment. I was amazed at just how quiet they are and with the one my brother had (from memory it is a 2000 watt) i could run two red heads. And there is a large range of wattages you can buy.


Andy.

Walter Graff January 11th, 2006 07:37 AM

QUOTE "A power inverter will not make your car's gas tank explode."

I never said that. I said it can cause a battery explosion, which I have seen it do. Inverters have nothing to do with your gas tank.


QUOTE " I don't know about you all, but I can do a lot with 600Watts of fluorescent light!"

A lot safer running 600 watts (or half the potential load than trying to use 1500 watts of an inverters 1500 watts. In fact I have yet to see an operators manual for an inverter that does not say "Do not use full load for more than 15 minutes." All I have seen say to never run more than 2/3rds the max power rating for any period of time..

QUOTE "I ran my household refrigerator (600W) for hours off my 1000W (1200W peak) inverter when there was a power outage. Over a year later, my truck and refrigerator are just fine. My truck was at idle and never stalled or made smoke."

Because your refrigerator cycles it's motor it really never runs 600 watts for any period of time other than initial start, probably more like 30 amps of DC required (3amps 120 volt AC) which is far below max. But an incandescent light requires 600 watts of constant energy and will damage your cars electrical system over time.


QUOTE "HERE IS HOW YOU USE AN INVERTER TO POWER LIGHTS:
1. Learn about your vehicle and battery's capabilities. Many compact cars have insufficient alternators for their own needs, nevermind the loads of an inverter. A Geo Metro with a tiny alternator and a miniscule battery will not suffice."


More detail needed. I would say that no ordinary alternator battery system has a return current of more than 90 amps on average. Remember that where 120 volts at 1000 watts is 8.3 amps of draw, 1000 watts at 12 volts is 92 amps. So already you are drawing near the limit of the systems capacity. The formula to figure it out is AC watts divided by 12 times 1.1 equals DC amps needed. So if you want to run a 600 watt lamp off an inverter you would need 55 amps of continuous power from an electrical system.

Turn off all other draws from the car such as radio, blower, lights so that only the inverter is drawing power. Fluorescents are the safest light to use with inverters. Incandescent lights draw a lot more current. Never max out your inverter, but only use 2/3 its total capacity for continuous operation is a good rule of thumb. Any draw over 500 watts needs a solid connection with nothing less than #2AWG cables and they should be attached appropriately (not just stuck in the hole between the screw that holds on the batteries connections but properly fastened using additional battery connections appropriate for the terminals of the battery. Never leave an inverter unattended running 500 watts of light or more. Have a fire extinguisher handy. During operation occasionally feel the inverters cables to the battery and the alternator body for heat. This is a clear sign of overloading. If the car is equipped with an amp gauge check it. If it shows 9 volts or less you are overloading the cars electrical system.

QUOTE "2. Get a powerful inverter with stepped sinewave or pure sinewave output. These make power most like that coming from the grid."

This suggestion sounds a bit off. Never get a powerful inverter just because it is powerful. Overrating an inverter is abetter way to say it. So a 1500 watt inverter would be a better choice than a 600 watt inverter. BUT, you will never use 1500 watts of power (you can not on most all passenger vehicles because the electrical systems could not deal with that much draw anyway). But the heavier duty electronics on a bigger inverter run at 1/2 it's continuous load rating is going to work easier than a smaller inverter run at its max. I would also not suggest a stepped sinewave inventor. It is NOT like power coming from your wall. Only a pure sinewave inverter is. In fact the best constructed inverters have pure sinewave outputs as they require the best electronics to make so are more expensive. Modified sinewave versions are cheaper to make and have cheaper electronics in them.


QUOTE "3. Get a GFCI (Ground Fault Circuit Interrupter) protected extension cord or a stand-alone protector that goes in between the inverter and cord."

This may not guarantee anything. You would be bette to get an inverter with GFCI designed into the circuit of the inverter itself. Many inverters today offer both GFCI and alarms warnings for such things as low voltage, etc. Adding breakers after the inverter in this type of situation may not offer safety when necessary or cause trips when you don't expect them due to surges.

QUOTE "4. With the vehicle running, connect it's terminals directly to the battery and not to the cigarette lighter. High-power inverters will tell you this in the instructions."

QUOTE"If your inverter does not have a fuse, build one inline with it's positive (red) cable."

NEVER build your own fuse into an inverter, it may not do what you need it to do when it should and in fact may break when you don't want it too. Rather ALWAYS get an inverter with built in circuit protection.


All times are GMT -6. The time now is 09:06 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network