Well to connect your inverter wires get some ring connectors big enough to accept 1/4" bolts cut off the present clips you had pictured strip back your wires and attach them to the proper poles of the battery (red is pos. and black neg) If you really feel the need to ground to the ground then get a clip and go to the neg. and stick your metal rod in the dirt.

You could also just plug that inverter into your cars cig lighter.

All this just to get some outdoor shots I presume- a long extension cord is another option!

hehe well when you are doing photoshoots at the beach, im not sure they make extension cords that long enough ;) but here is what i have done so far with the wiring :) the only thing im concerned about is grounding the inverter.. i hears lots of sides saying it doesnt need to be ground because its a floating type system, then i hear others say it NEEDS to be grounded to be safe. OR i could use a portable GFIC what kind of GFIC would i need for all the specs i have here?

Here are the pics of how i installed the wires.

Dear Dr Tom, you said "You could also just plug that inverter into your cars cig lighter."

NEVER EVER DO THIS !!!! At best you will blow the fuse for the Cigarette lighter socket, at worse, you could set fire to the cars wiring!!!

Most GOOD car cigarette sockets can take about 8-10 amps thru them, not more!!!!!!!!!! Cheap ones maybe only 4-5 amps.....

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To this Blog:-

This converter (probably bigger than needed, but we have little info as to what mains current is needed!) will draw 25 amps at the 12 volt level. Use normal car battery connectors with a snap-on snap off function.....sometimes sold at caming stores as well.

Even the batteries (please do not consider running them in parallel, there are even more problems that could occur!) will theoretically run for something over 1 hour at best.

BUT if the batteries are normal car batteries and you use them for the full charge, the end voltage will be well under 12.6 volts, which is the point at which damage from deep discharge starts.......so their life span will be very short, they may stop working within the guarantee time, but as deep discharging is usually not covered by the guarantee anyway, you will still end up buying new ones!

What is really required is a "Leisure" battery of largest proportions that can be handled, I would suggest at least 125 A/H.....also switch off converter when not needed.

Leisure batteries handle deep discharge much better than car batteries, but are more expensive as a result.....

If converter is "too large", buy a smaller one to conserve battery power!

I have only touched on a few important points, not all of them.......

Next problem, what sort of charger did you buy???? Cheap ones damage batteries!!!!! They are only good for a short charge before starting the car, not more!!!!

I would use the wires with the spring clips that came with the inverter. The manufacturer should know the current draw of the inverter and have designed for it. I have a 300 watt inverter and it runs just fine that way.

The wires included with the inverter is all you need. They should be greater than 22g most likely 14g. The amps of the Strobes will dictate the size of the inverter. Amps * 100V to 120V = Watts needed. A 15amp circular saw needs at least a 1500 Watt inverter with 2100 Surg Watts. A 1500 Watt inverter requires 10g wire. Amps is what you need to know from there you should be able to find the correct size wire. Wire size is often listed on crib sheets at most Lowe's and Home Depots for new employees to use. This should help some. In most cases no ground rod is required. Some transmitters need to be grounded for tuning purposes. I don't see you needing to take the time and effort to drive a rod at least 2 feet down every time you need to use the inverter.

see that is what i thought... but people keep freaking out saying YOU NEED TO GROUND IT!!!! so im just trying to be safe but sometimes i cant drive a frickin stake in concrete.. so im just trying to make sure i do things safe though.

The battery you're looking at is about the size of a motorcycle battery... My thought here is have you made sure that when you get this all together, you'll have enough power to run your flash unit? I have a Speedotron that would eat that inverter for lunch.

Just make sure you check everything in the opposite direction. In other words, check what the required operating power of your flash supply is and make sure your battery and inverter can give it the power it needs.

Also, since your inverter and your flash unit both use three-prong plugs, I think all you really need to do is make sure the "case" of the inverter is grounded.

Jacob wrote:

see that is what i thought... but people keep freaking out saying YOU NEED TO GROUND IT!!!! so im just trying to be safe but sometimes i cant drive a frickin stake in concrete.. so im just trying to make sure i do things safe though.

REPLY

Jacob relax! You have done a pretty good job of wiring the battery and inverter together. Only by using the system will you find out if improvements are needed. This is totally dependent on how much current your flash gun draws during recyklcing between flashed. I suspect it doesn't exceed 15A.

Concernin ggrounding:

Several companies have made packaged products very similar to what you have. Statpower was the first to package a battery and inverter this way back in 1998. Since then it has been copied my numerous competitors. These are UL certified and do not require you to drive a ground rod.

You have chosen a good type of battery that can handle deep discharge cycling. I would recommend that you buy the charger offered by the retailer you bought the battery from. I see them listed on their website.

If it turns out your flash unit requires more power as a peak surge, then change the wires to the largest size that fits the inverter terminals. From the close up pic I think these are the #8 Ga size. The factory supplied pin lugs are not the best. Get some ferrules that have a round shape before you crimp them. I get mine from AMP but I normally use the smaller sizes from #10 Ga and down to #18.

The choice of the Anderson connector between the battery and inverter is also a good one. I probably would have selected the 20 A unit instead of the 15A to lower any conductor resistance in the path between battery and inverter. But that would also have made it harder to crimp that #10 Ga wire supplied by the inverter company. If you remake the assembly to improve the surge capacity keep the cables shorter. It looks like you have about 36" of wire between battery and inverter. Statpower ( now called Xantrex) used #10 wire between battery and inverter and this wire was only 10" long. I have three of these units at home and use them for everything from starting my car to powering computers during power outages.

Your battery terminal connection os good. The only thing that might be improved on is if you got thicker lugs made of tinned copper. Thomas and Betts or Burndy make some really good ones

This is the Battery Charger i decided to get after much research and Ive heard good things about this one.. plus it seems simple and straight forward. Also I was thinking of using the same plug connector i have set up from my inverter to my battery and splice that from the charger so it plugs nicely into the battery.. whats the best way to splice and combine a wire? solider it? ( i don't have a solider ) or just twist the wires together and tape it? or is there a recommended crimp piece that most people use.. im just trying to make everything professional as possible I know it seems anal but I dont wanna burn down my condo lol

BatteryTender 021-0128 Plus 12v 1.25 amp

All Battery Tender battery chargers are designed to fully charge and maintain a wide range of styles of lead acid batteries in ways that avoid the potential damaging effects that can be caused by most trickle chargers. All Battery Tender battery chargers have the five following characteristics:

• Fully Automatic: At the end of the regular charger cycle, every Battery Tender battery charger automatically switches its output voltage to a safe, storage or float level that eliminates the need to constantly check on the conditions of the battery.
  
  
• Full Output Power at Low AC Line Conditions: Battery Tender battery chargers will deliver full output power with input AC line voltages as low as 90 VAC. (Excluding chargers with output current of 2 amps or less).
  
  
• Zero to Minimal Current Draw from Batteries: When the AC power is disconnected, most Battery Tender battery chargers draw zero current from the battery. A few of the higher power models draw less than 1 milliamp from the battery.
  
  
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Jacob, the charger already comes with a plug and socket adaptor complete with ring connector. Use it. You are only dealing with a trickle charge of 1.25A if I read the spec corectly.

Don't waste your time modifying the other plug. Just wire this adaptor in parallel. From the photo it looks like you plug in either the clip-on or the permanent ring connector end.

Is there anyway to measure how long the battery will last during a shooting session if i run three strobes from it?

Power Requirements for each strobe:

120 Vac, 50–60 Hz

6 Amp Circuit Breaker

320 True Wattseconds

800 Ws effective Wattseconds

is there any other info i need?

Jacob wrote: 320 True Wattseconds, 800 Ws effective Wattseconds

WATT SECONDS!!! And here we thought you were talking about power hungry devices. There are 3600 watt seconds in one watt hour. The battery has a capacity of 35 Amp hours so 35A X 12V = 420 Watt hours. You will get approximately 10 flashes per watt hour. Even using the 800 effective watt seconds value, that means four flashes per watt hour.

So you get 10 X 420 = 4200 flashes or divide by three if you use three units per photo snap. Roughly 1400 shots from a full charge. Your bloody camera will die before then. ( grin)

WOOHOO!!!! dam i love you guys!! things are certainly looking like i did the right thing here :) and i have TWO batteries!!! so i think i will be good to go for a long time :) so is my inverter powerful enough to power 3 strobes? so it looks like my rig is pretty solid then? thank you guys SOO much for all your help.. i dont know the first thing about electronics and you guys have DEF helped me out alot :) Ill post some pics i take tommorrow of this cute gal who is going to pose with her kick drum :) if anyone is interested of course

Sorry, this is more for me, than Jacob...

The Watt seconds or (joules) is the output power of the flash unit. This does not necessarily reflect the amount of power that the flash unit tries to draw from the mains. That depends more on circuit design regarding recycle time, and a lot of other things. Shouldn't Jacob be looking for the input Volt and Amp rating of the flash unit?

Vermin wrote: The Watt seconds or (joules) is the output power of the flash unit. This does not necessarily reflect the amount of power that the flash unit tries to draw from the mains.

I'm not that familiar with how flash units are rated electrically. It may well be that the 800Ws (effective) is the power consumption rating and the 300 WS is the light flash output. Which is why I did the second estimate. Either way the battery pack will provide power for a lot of photos.

As far as draw from the mains, unless this is a super high powered flash it will not draw many amps from a 120V outlet.

All th flash units I have seen professional photographes use only draw something like five amps and then only for a short while.

I used to work for Statpower as a sales/applications engineer so I had a chance to disassemble their power packs as well as a few of the competition. Typically they use a 20A-H battery. I can start my six cylinder 5 liter engine four times on that power pack.

The power pack has direct battery connection as well as a connection to a 300 watt inverter. The inverter will run a radio for a full day and a 60Watt filament bulb lamp for five hours plus.

Jacob's 35 A-H pack is more than 50% bigger so it will run for a loooong time.

Elnav

The Watt seconds is always the output power of the flash unit. It lets you know how big or small your xenon tubes should be. Typically, there is more than one cable connector for more than one flash unit to be triggered at the same time - absolute Ws is divided among these connectors in various different energy configurations. Usually there is also a value if you want to drop all the stored energy through just one big flash lamp. I think that's where the 800 Ws number comes from.

My supply can drop 2000 joules through a single lamp... Yes, I've created very expensive sand this way before. Anyway, I'm guessing that how fast you can cycle to another flash probably depends on how much current the flash supply draws from the mains.

Jacob, are there voltage and current requirements marked on the back of your flash unit?

on the back it says

105-125VAC

50-60HZ 6A

And here is the FULL specs of the units from the website

AlienBees Technical Specifications

specifications

B800

true wattseconds

320 Ws

effective wattseconds

800 Ws

lumenseconds

14,000 Ls

power range

5 f-stops
(full to 1/32)

recycle to 100%

1 second

flash duration at full (t.5 method)

1/3200th second

sync / trigger voltage

less than 6 volts

power requirements

120 Vac, 50-60 HZ,8 amps

internal cooling fan

yes

modeling lamp

150 watt max

flashtube

10mm single-ring

Quantity of electrical energy is measured in Wattseconds, also known as Joules. This rating defines the amount of electrical power discharged with each flash. While the actual amount of light produced for a given number of wattseconds varies, depending on the unit's design, the term provides a reasonable guide to comparative light output, as long as real/true wattseconds are specified. In the conversion of Watts to Lumens, or Wattseconds to Lumenseconds, the efficacy of the system determines how much light will result from a given number of wattseconds. The poor efficiency in this conversion by manufactures has given rise to the term Effective Wattseconds. If one flash system converts 400 Wattseconds of energy into 16,000 Lumenseconds of light, and another flash system converts 800 Wattseconds of energy into 16,000 Lumenseconds of light, then the first system could claim to have "800 Effective Wattseconds" as it is effectively producing the same amount of light as a system starting with 800 True Wattseconds. The Effective Wattseconds rating, however, is rather arbitrary and cannot be easily proven true or untrue, as it is merely used as a basis for inflated comparison of different flash systems.

Power Range Increase

The Power Range of all Flash Units is extended by 1.2 f-stops when the RadioRemote One wireless remote control system is used.

Flash Duration (t.5 method)

When a flash system fires, although it may appear so to humans, the light emitted does not come on and go off instantaneously. In reality, the flash tube 'turns on' very quickly and then dims gradually as the flash capacitors discharge. Short flash durations are important to prevent blurring when the subject is in rapid motion such as a pirouetting ballerina or a Michael Jordan slam-dunk. Flash manufacturers do not rate flash duration as the entire time the flash tube is emitting light however, because the end of the slowly dimming 'tail' does not contribute much to the overall exposure (or to blur). t.1 is defined as the time during which the flash lamp output is above 0.1 (or 1/10) it's peak intensity. t.3 you may guess is the time the output is greater than 0.3 (about 1/3) peak, and t.5 is how long it's above 0.5 (half) the peak value.

Sync/Trigger Voltage

When using digital cameras, it is best to check on the maximum sync voltage allowed for your specific camera. Most other brands of flash units have sync voltages much higher than ours, some as high as 50-60V, but the sync voltage on all of our AlienBees flash units is under 6 volts, safe for use with digital cameras.

output measurements B400 B800 B1600 Standard 7-inch Reflector f11 2/10 f16 2/10 f22 2/10 11-inch Reflector f22 f32 f45 48" Silver Bounce Umbrella f8 - f11 f11 - f16 f16 - f22 48" Shoot-Thru Umbrella f5.6 - f8 f8 - f11 f11 - f16 Medium Softbox f11– f16 f16 – f22 f22 – f32

The output readings have been measured with a Gossen Ultra Pro flashmeter (ISO 100) placed 10-feet from the flashtube for direct reflector specs, 10 feet from the center of the radiating fabric for umbrella specs, and 4 to 6 feet from the center of the radiating fabric for softbox specs. Measurements were taken in the center of 20' x 27' white room with 20' ceilings. Readings may vary when taken in other environments and with other meters, as different brands of flashmeters can vary by as much as 1 whole f-stop in their interpretation of "correct" exposure values.

The following accessories were used for these measurements:

7AB/R: The Standard 7" Reflector on the AlienBees Flash Units (silver field reflector, 80º beam spread); 11R: The 11" Reflector (silver long throw reflector, 50º beam spread); U48SW: 48" Silver and White Reversible Umbrella (silver side used for silver bounce reading), U48TWB: 48" Shoot-Thru Umbrella (black cover removed for diffused reading); and SB2436: 24" x 36" Medium Softbox (silver lined rectangular softbox, double-diffused with the second internal diffusion panel in place).

guide numbers B400 B800 B1600 Standard 7-inch Reflector #118 #172 #236 11-inch Reflector #220 #320 #450

The Guide Number (GN) is a standard measurement serving to indicate a flash unit's output by calculating the distance times the f-stop, with respect to the film speed. The guide number relates the film speed to the actual flash output. A Guide Number is determined by placing the flash unit at a desired distance from the subject (usually 10-feet), and metering with an accurate flash meter. The guide number can be calculated from the distance and the f/stop (GN = f/number x flash-to-subject distance).

We get a lot of questions asking, what is the "guide number" of your flash unit? This term is not wholly reliable because it relates more to the angle of the reflector than to the actual amount of light produced. For example, a flash unit with a given amount of light output will register a much higher guide number (f-stop at 10') if it has a narrow angle reflector (for telephoto lens) than if it has a wide angle reflector. But the actual amount of light is the same in both cases…it just covers more area with the wide angle reflector (at a lower guide number). In comparing flash units, the max GN of a flash unit is usually given for ISO 100 film. When it comes to choosing a flash unit, you have to be careful, as these measurements can be altered. It is common practice within the flash unit industry (for marketing reasons) to provide the max GN at the smallest coverage, as this will provide the longest focal length. Such a focused flash unit is more powerful, which produces a higher Guide Number, implying a more powerful output. Therefore, the max GNs of different flash units are usually not directly comparable. Studio flash units are designed to be used in many different configurations, with different accessories. The angle of coverage will be different in each case as will be the achieved guide number for a given amount of emitted light. As merely an indication of output, we publish the max guide numbers, noting that they are not true measurements of what you can do with our lights, as the real output will be determined by how you choose to modify the light.

These output readings have been measured with a Gossen Ultra Pro Flashmeter (ISO 100), placed 10-feet from the flashtube for direct reflector specs. The readings represent the output of each unit at its full power setting. Readings were taken in the center of a 20-foot x 27-foot white room, with 20-foot ceilings. Please note that readings may vary when taken in other environments and with other meters, as different brands of flashmeters can vary in their interpretation of correct values. The stated maximum Guide Numbers (GN) were calculated by multiplying the distance (10 feet) times the measured output in f-stops.

weight/dimensions B400 B800 B1600 weight 2.5 pounds 2.9 pounds 3.7 pounds dimensions 9" x 7.5" x 5.5" 9" x 7.5" x 5.5" 9" x 7.5" x 5.5"

elnav,

OK, so his flash supply uses the following:

power requirements

120 Vac, 50-60 HZ, 8 amps

Is his rig big enough to handle that? I defer to you, elnav, who is of greater knowledge than myself.

Vermin wrote: 120 Vac, 50-60 HZ, 8 amps Is his rig big enough to handle that?

REPLY: that is going to be a problem. That 300 watt inverter will not handle 8 amps for a one second duration. 300 watts at 120V = 2.5 amp draw. Even if you use the peak surge rating of 2X that's only 5 amps for a short duration of maybe 5 seconds.

In addition, the wire harness supplied by the inverter maker looks like it might be #12Ga possibly #10Ga but I would not count on it. This will cause the DC voltage at the input terminal of the inverter to drop compared to the voltage at the actual battery post.

To deliver a consistent 8 amp burst of power every time the flash recharges would require at least a 600Watt inverter. And that unit will be pushed somewhat hard. As long as the flash is not cycled at more than 10 second intervals it probably would work with a 600Watt inverter.

If the 8 amps mentioned on the rating plate refers to the peak amp draw during that one second recharge cycle time, then we are looking at 960 watts draw for one second. A 600 watt inverter can handle twice it's rated continuous output for a period of five seconds or less. The output stage will heat up. But if you do not demand this surge more frequently than 10 - 15 seconds apart the unit has some time to cool of in between. The unit will heat up faster on a hot summer day at the beach than at night or on a cool day.

Now that I know the actual AC demand, i think I would rebuild the package somewhat. Battery is ok. Wires should be #8 or better yet #6. Keep the wires very short. Perhaps no more than 18" max between battery post and inverter terminals. For disconnect purposes I would use 20Amp Anderson connectors. It looks like Jacob used 15A connectors.

Also use Burndy or T&B solid copper lugs that are at least 1/16" thick metal. Use the larger flag style connector that has more surface contact area to mate up against the flag posts on the battery.

On the inverter end, use tube ferrules that create a solid pin out of the stranded wires when the ferrule is crimped shut. Its my guess a hex crimp for an RG58 sleeve crimp or maybe one of the cellular car phone crimp tools would do if the exact crimp tool is not availabe. My ratchet crimp tool has interchangable die sets for every kind of connector crimp.

regards

Arild

I would not ground the unit, why you may ask. Well if you ground it correctly and accidently touch the phase, you will most likely get one hell of a belt from it!

But if you don't earth and only touch one of the terminals, you will probably feel nothing or just a slight tingle!

If you touch both live and neutral at the same time, you will get a good belt of course!!

Buy an ELCB...... which you will need to buy and install - if you want safety.