Have you ever put together a studio power supply?

[beeman458]

Has anyone put together their own high power, 12v, auto style,

battery pack power supply with power inverter? I'm curious what your

experience has been.

 

I'm in the process of putting together a portable power supply for

studio power pack/flash heads. The system is being designed to

handle a pair of Speedotron D402's and a pair of Speedotron D1204's.

Each unit is 10amps.

 

Currently I have a pair of gel cell technology, Optima, 1050 CA @ 32

degrees F, redtop, batteries. To keep the batteries at full charge,

I've attached a 5W solar panel, Solargizer Solar Charger

by "PulseTech". To the top of the battery I'll attach a Tsunami

battery topper. (Way cool toy. It has #1ga/#8ga wire clamps lugs and

a digital read out for voltage.) Lastly, I'll attach the

battery/topper to a power inverter. I think the usable energy of

each battery will be about 75amp hours.

 

I realize the redtop Optima battery isn't a deep cycle battery and

will eventually pick up either a pair of yellow top or blue top,

which are deep cycle, to replace the red top batteries that I

currently have.

 

The system won't be as pretty as, say, an Elinchrom, battery pack but

I suspect that the power supply, one battery, will hold a lot more

capability at about half the price. Batteries are about $130.00

(US). The battery topper I picked up at e-Bay auction for a $120.00

(US), including shipping. The Solargizer solar charger sells new for

$250.00 (US) but picked it up at e-Bay auction for about a hundred

bucks. So for the pair of 12v gel cell Optima batteries, Tusanmi

battery topper and Solargizer charger, I've spent about, round

numbers, $480.00 (US). If you throw in a decent power inverter at e-

Bay auction, 5000w/10000w, which runs an additional $500.00 then a

rounded thousand dollars.

 

After all this expenditure and effort, one will have about 150amp

hours of on site energy for a full four light, 3200ws, portable

studio lighting. Will I be happy with the final package or will I be

whining that it wasn't enough portable power:)?

 

I'm curious what your experiences have been with putting together

your own portable power supply for your studio lights. Any short

falls that I should be made aware of? Will two batteries be enough

or do I need four in the kit? Any insight will be appreciated.

 

Thanks! And looking forward to reading your personal experiences or

professional insights.

[bill c.]

Thomas-- That sounds like a really cool kit, though I'm not certain the steppers will be able to keep up with the drain during recycle. You sound competent enough to have spec'ed it out properly, but sometimes the recycle current drain can be momentarily awsome. The manufacturers sometimes count on sucking the AC 120 in high-amp pulses that can go as high as 25 or 30 amps but won't blow a household circuit because they're so short in duration.

 

But one important thing I can point out to you is that you may be re-inventing the wheel, albeit for a different brand of strobe. Paul C. Buff and the techs at White Lightning (and also Alien Bees) have a 12-volt battery powered AC conversion kit quite similar to what you have put together, but it works only for the Bees/White Lightning equipment. If memory serves it's about $130 for the smaller configuration. Check it out at www.alienbees.com. Basically, you can buy two 1600 WS equivalent Bees and the battery AC kit for about what you're paying to put together your power supply. If you want things better built, you can move up to White Lightning for about $150 bucks more.

 

Will 3200 WS be enough? That's hard to say, as it depends on what you do. If you're cranking out catalog shots at the rate of 100 rolls a day, probably not. But if you're shooting 5-10 rolls at a time of some location fashion, you probably won't need much more than f5.6 or f8, which should keep power requirements to a moderate level.

 

Frankly, for extensive location shoots where no AC120 is available, I've just brought along a quiet gas-powered generator. My Comet strobes can be set to five levels of recycle draw, so I can dial them down to accommodate nearly any watt output. The battery kit you're putting together seems quiet and nice, but I'd wonder how much time it'd give you on the modeling lights. Depending on the conditions, the modeling lights may draw as much power as the strobes.

 

Best of luck with the system. -Bill C.

[beeman458]

Bill wrote<p>

 

<i>Thomas-- That sounds like a really cool kit, though I'm not certain the steppers will be able to keep up with the drain during recycle.</i><p>

 

Thanks!<p>

 

Having run that thought through my head, I figure if you're right, then I'll have to create a split system where instead of one power inverter and battery being used, I'd split the system into two seperate power inverters and batteries at the same time so the immediate capacitor recharge draw will be off two different battery/power inverter systems. That way the system would be more responsive to power demands. If need be, I've considered bring in two more batteries to create a 24v system as opposed to a 12v system. I just don't want to get too carried away with this idea and then find out, after the fact, it was really a bust in the making:)<p>

 

<i>You sound competent enough to have spec'ed it out properly, but sometimes the recycle current drain can be momentarily awsome. The manufacturers sometimes count on sucking the AC 120 in high-amp pulses that can go as high as 25 or 30 amps but won't blow a household circuit because they're so short in duration.</i><p>

 

I've read similar comments here on several recent occasions. The spec sheet for the Speedotron Brown Line of power packs, claims a 10amp max draw. The power inverters have slow blow circuit breakers which hopefully will be able to handle these momentary surges in current demands. Using four batteries to create a 24v system with a split, two inverter system, will run the final price up to close to two k (US). In the beginning I had visions of a wonderful, portable, non-gas powered supply system in the five to seven hundred dollar (US) range:) Oops! :)<p>

 

<i>But one important thing I can point out to you is that you may be re-inventing the wheel, albeit for a different brand of strobe. Paul C. Buff and the techs at White Lightning (and also Alien Bees) have a 12-volt battery powered AC conversion kit quite similar to what you have put together, but it works only for the Bees/White Lightning equipment. If memory serves it's about $130 for the smaller configuration. Check it out at www.alienbees.com. Basically, you can buy two 1600 WS equivalent Bees and the battery AC kit for about what you're paying to put together your power supply. If you want things better built, you can move up to White Lightning for about $150 bucks more.</i><p>

 

Thanks for your above as I'm not trying to reinvent the wheel. You're very correct when you comment that the wheel has already been invented. What I'm trying to do is create a realistic portable power supply that can get the job done, to blue collar, macho man, weld a battleship, steelworker, construction standards, as opposed to white collar, looks fancypants sitting on the floor in a cube farm, office worker standards:) (And people, please don't go on the offense, it's a joke.) Think "Tim", "The ToolMan", "Taylor", as in "More Power.", "Ar, Ar, Ar" :)<p>

 

<i>Will 3200 WS be enough? That's hard to say, as it depends on what you do.</i><p>

 

I might have confused you with this one. I was meaning to convey the question; Would the power supply described, be sufficient to keep 3200ws worth of power packs happy? This, as opposed to; Is 3200ws worth of lights going to be enough light? I'll try to be more articulate in my deliniations:)<p>

 

<i>If you're cranking out catalog shots at the rate of 100 rolls a day, probably not. But if you're shooting 5-10 rolls at a time of some location fashion, you probably won't need much more than f5.6 or f8, which should keep power requirements to a moderate level.</i><p>

 

I would be needing enough energy for about fifty to a hundred pops and would want, for architectural images, at least f/11 if not f/16 for decent DOF. I would be using digital and currently get a very clean ISO 200. With the next generation sensor body, I expect to get a very usable ISO 400 if not a very (by advance reports) usable ISO800. Now that would be sweet! :)<p>

 

<i>Frankly, for extensive location shoots where no AC120 is available, I've just brought along a quiet gas-powered generator. My Comet strobes can be set to five levels of recycle draw, so I can dial them down to accommodate nearly any watt output. The battery kit you're putting together seems quiet and nice, but I'd wonder how much time it'd give you on the modeling lights. Depending on the conditions, the modeling lights may draw as much power as the strobes.</i><p>

 

Believe it or not, I hadn't considered the affects of the modeling lights on power consumption:( "Doh!" From some of what I've read here, even generators have their power demand capability shortcommings. Everything says that I'd need two generators for what I'm wanting. Even so, a quiet Honda generator might still be in my very near future:) I have a tendency to ask for too much, from too little, at an affordable price:) <p>

 

<i>Best of luck with the system. -Bill C.</i><p>

 

Thanks. Based upon your comments, it seems that I'd be better served by starting out with a 12v/24v system and a 3000w/6000w, 12v/24v power inverter. It seems I should also give Speedotron engineers a call and find out what the momentary recharge draw is. Maybe they'll be able to give me some insight as to the shortcomings of a batter/power inverter system such as the one being cobbled together as opposed to a quiet gas generator.<p>

 

Thanks for your thoughts as they've given me some excellent points to consider.<p>

[beeman458]

Been doing some more research into battery technology for this portable power supply that I'm cobbling together. It seems that car audio has pushed battery technology further down the road then at first blush, one would realize unless you're into putting high powered auto sound systems together. This is a good thing. Why? It seems the EFX line has 1700CA battery with all the fancy cabling a gearhead could want. Both the EFX line and the Rockford Fosgate line have some very well developed connectors, cabling and batteries, not to mention Rockford Fosgate has some killer capacitors in the 25, 50 to 100 farad range for instant surge power needs. I'm sure there's much more out there that some on this board are knowledgeable about as I'm just opening my eyes to the possibilities which Auto Sound Technology will provide to help complete this quest of mine:)<p>

 

Here's a link to a 1700CA battery that EFX puts out, on e-Bay that one can buy right now for $250.00 (US), plus shipping. The offical description lists the power reserve in minutes as opposed to the standard of Amp Hours, A.H. I have an e-mail into the manufacture's tech-support group to see what the A.H. reserve on this beast is.<p>

 

<a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=1498&item=3087157827&rd=1">EFX 1700 CA, 12v drycell battery</a><p>

 

Here's a link to a buy it now, e-Bay auction, for a 100 farad capacitor by Rockford Fosgate.<p>

 

<a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3085896268">Rockford Fosgate 100 farad capacitor"</a><p>

 

This is a more reasonable 4.4 farad capacitor. It has a built in buss bar and a voltage read out on the top:)<p>

 

<a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3072750648">4.4 farad capacitor with buss bar.</a><p>

 

Just wanted to share a little of what I've come up with as I research and put together a high volume/capacity, battery based, portable power supply for on site studio lighting.<p>

[beeman458]

Just finished with the phone call to Speedotron Tech Support. The tech stated that max amperage draw on their line is the stated limit. So all of the Brown Line power packs, with the sigular exception of the D202, have a peak power demand of 10 amps peak.

 

When asked, he said there isn't a momentary peak surge demand of twenty or thirty amps, as other's have suggested. There may be a momentary peak amperage demand with other power packs but this is not the case with the Speedotron Brown Line or Black Line power packs.

 

The only verbal note he made sure to bring to my attention was, the Black Line power packs needed a "true" sine wave power inverter source and the Brown Line would handle current from "modified" sine wave power inverter. Timber wrote about this point in an earlier post. When asked, he said that using a 3000w/6000w power inverter, that he didn't feel a high volume capacitor was necessary. A decent deep cycle battery, coupled to a quality power inverter by some #2 awg wire and one should be good to go:)

 

This is a good thing:)

[mike dixon]

One spec you haven't mentioned when describing the system you're assembling is weight. I noticed that just the battery in your link above was almost 60 lbs (compared to about 15 lbs for the Alien Bees or Elinchrom systems). If the locations for which you need "portable" power have stairs, sand, gravel, or other wheel-unfriendly obstacles, you're going to have a problem. Unless you or your assistant does serious weight training, carrying that kind of load for any distance is not a trivial task.

[beeman458]

Thanks for the thoughtful concern about the weight:) Being a blue collar worker bee, weight, such as a sixty pound battery, for short distances of a few hundred feet or a couple three flights of stairs is not a problem:) Wish I could say I was twenty-seven again but I'm not:(

 

I have one more spec number I need to find out; What's the standing draw of the Brown Line series of power packs when just plugged in and sitting there at the ready?

 

Optima has a sixty pounder (D31M) that has 75 A.H. of ready reserve, with both SAE auto posts and 5/16" studs which I have found online for $147 (US) plus shipping.

 

So far, this is getting better and better. For a portable, quiet, non-gas power supply as a portable studio lighting energy source, this seems to be coming together nicely:)

[beeman458]

Just an update on where I'm at with this portable power supply.<p>

 

This morning I order up a redundant battery system. The two battery systems, each consist of an Optima D31M, 75 amp hour, deep cycle, marine environment, gel cell battery. One battery as the primary battery and then a second battery pack to back the first one up, should it be needed.<p>

 

<a href="http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=2473056592&category=31284&sspagename=WDVW">e-Bay auction for Optima D31M 12v battery</a><p>

 

A cheapo plastic marine case @ $9.50 each, will provide additional impact protection as well as serve as a carrying case with handles. In addition to the battery and case, each battery will have it's own trickle charge, battery maintainer to supplement the standard, quick charge, battery charger which most households have on hand in their garage.<p>

 

<a href="http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=35557&item=2473056769">Trickle charger, 12v battery maintainer </a><p>

 

Price of a pair of Optima, D31M 12v, deep cycle batteries with protective cases and individual trickle chargers, ordered over the phone from the company listed in the links above, with shipping, will be a grand total of about $475.00 (US).<p>

 

To the above setup, I'll add a 3000w/6000w, marine power inverter.<p>

 

<a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=32814&item=3091687215&rd=1">e-Bay auction, 3000w/6000w marine power inverter </a><p>

 

Two points. I went with the marine power inverter because it has GFI's (Ground Fault Interrupt) on the outlet plugs (safety) and construction of the unit has better weather sealing against dirt, dust, sand, vibration and or salty moisture ladened environments. This will protect the unit as it's knocked around in transport and while on windy location; beach, mountains, desert or abandoned warehouse. This is a good thing. :)<p>

 

I also am going with a split, two inverter system as opposed to one inverter. As one draws on the stored energy in a battery, the faster the draw on the stored capacity of the battery, the less available energy a battery will have to give.<p>

 

<a href="http://www.majorpower.com/inverters/battery_sizing_faq.pdf">Energy draw and requirement information sheets.</a><p>

 

If this system works out and has the capability to support two Brown Line power packs, should I have need, I'll then put together a second power inverter, battery pack combination. This is being done for cost reasons as the total on one system is about $850,00 (US) We won't mention the good money that I've thrown away, as I ran in the wrong direction with this idea:) Should the system work and I have need, I'll be happy to hit the hip for the second setup. But in the interium, I figure fiscal conservation on a whim of an idea that won't get used very much, if at all, is a good thing:)<p>

 

Two battery packs have been ordered and I should receive them in ten days or so. Once I have them in possession, I'll then be able to make the next step and order up the power inverter and proper cabling. I don't want to order the inverter until I have the batteries in possession so if the inverter supplier has any questions as to the battery, I'll be able to answer their questions so as to get the correct interconnects between the battery and inverter.<p>

 

It'll probably be another month before I finish ordering, receiving and putting everything together. At which point I'll run usage tests and post test results and pics of the final assembly under another heading.<p>

 

I'm not trying to reinvent the wheel here but I can assure you, the wheels that I do come up with are, hopefully and with high hopes, going leave tracks up and down the backs of all the other wheels out there. I expect the system idea to be universal in nature, applying to the needs of "all" studio lighting systems, at a final price that leaves a lot less green on the purchasing table, gives a lot more available easily portable stored energy and won't require gasoline or make any noise in the process. This is a good thing. :)<p>

 

The one short fall of the particular system I'm describing here and putting together is that it uses a modified sine wave as opposed to a pure sine wave electrical power inverter and so this particular system I'm putting together will, for all intents and purposes, apply only to transformer units such as those found in the Brown Line power packs. Sorry! Pure sine wave power inverters cost a whole bunch more and change the pricing curve considerably for the intent of this study. That's a bad thing. :(<p>

 

I'll post again when I have additional information to share.<p>