Paul C. Buff, Inc. Technical Forum

I have been sitting on the fence considering whether to buy the Vagabond 2 or purchase a pure sine inverter. I do like the AB product line and do have faith in it, but wonder if perhaps the Vagabond was built more for portablity (keeping it small and reasonable weight) than as a substitute utility source.

I really want to be able to take advantage and fully use the modelling lamps in my strobes when in the field. I understand the relationship of load to battery capacity and am prepared to haul a full sized deep cycle lead acid battery (or two) around for field shoots. So my question is, battery capacity aside (and solved by my use of additional batteries), is the Vagabond itself capable of running (4x) B1600 strobes with their model lamps at full power (150 watt lamp used in each strobe).

Does the carrying bag allow enough airflow for cooling? Other than havng the top flap fully open are there any additional air paths?

What gauge are the cables that come with the unit and that are intended to be used for remote / seondary batteries.


Thank you for any information you can provide,

Spyglass

4 b1600s are rated for approximately 120 full power pops. The only ventilation I see is from the the tops of the inverter. modeling lamps are a huge no. its a big draw on power to continuously use them. If you're outdoors though, the modeling lamps on the b1600's won't be visible unless its pretty dim out. I don't know what gauge the cables are though. sorry. I'd go with a generator if modeling lamps are a big deal for you.

Thanks for responding Ptlphotostan. The 20aH battery that comes with the Vagabon is probably ok for someone that wants quick easy portatbilty, something that would appeal to me at times. I have two 120AH deep cycle batteries that were purchased during a large UPS battery change out project. So DC / battery power is not an issue for me for the times when I would required it. I have designed a (hand cart) dolly system for transporting the batteries c/w large off road wheels.

My concerns are more with the continoue duty rating of the Vagabon. On most of the Inverters you can buy they indicate a continuous and a peak / surge wattage rating. I heard a rumour that the Vegabon was able to handle the inruch current required to charge the capacitors in several strobe units, but not able to sustain a high current level without over heating. I am also curious as to the nature of the slow and fast recharge rate switch. When set to Fast will is operate like a conventional inverter? What is the actual effective wattage of the Vagabon does the model number imply that it is a 1900 watt inverter? Is that Peak? Continous?

I fully aggree that the modelling lamps are not as effective in outdoor situations, but I have a project under the forest canopy were light levels are very low. There is also the option to shoot at dawn, dusk, or at night.

Any advice would be welcomed, perhaps the Alienbee techs or Paul might have some information that could help me get off the fence.


Thanks,

Spyglass

Most inverters not designed specifically for charging flash units have a peak rating approximately double the continuous . . . 600W peak for a 300W inverter. When loaded beyond the peak capability, most go into shutdown mode.

The peak power a line delivers to a single AB or WL of any WS rating is about 2000W (16A). The same applies to most competitive monoflash units. A Zeus or Dynalite power pack asks for about 6000W (50A) from an AC powerline.

Some sine inverters (such as Vagabond) current limit when a load greater than the specified peak load is presented. Without the current limit function, inverters below 1000W continuous rating will not charge one studio flash, let alone multiple units. Of necessity, when an inverter current limits, its output voltage drops to as low as 50VAC. Many flash units won't tolerate voltage drops below 90V or so, and can crash.

Neither the ability to current limit nor the characteristics of the current limit mode are normally specified for off the shelf inverters. Also, the crash-free minimum voltage is rarely specified for studio lights.

Because of this, assuming a certain inverter will power a certain flash unit, or a number of flash units is a crap shoot.

Regarding the original question, Vagabond II has a continuous power capability of about 400W and current limits at about 6A output. It can operate multiple Buff lights but we make no attempt to define if and how many lights from other manufacturers it can operate because there are so many variables.

As for the fast slow switch, we're on our third supplier of inverters and none of them have ever implemented the slow function as we have specified it. The slow function is supposed to drop the current limited output to 2.5A, (approximately the same as the original Samilex 300W inverter used in Vagabond 1) (This inverter is no longer made). The purpose of the slow function is to reduce the current drawn from the battery to allow smaller AH batteries to be used, and to gain more flashes per charge because of the resulting higher efficacy of batteries at lower output currents.

In reality, the slow switch only drops the current limiting to about 4A output and has little effect.

There is very little vendor capability in the US for effective pure sine inverters at reasonable cost so we are stuck with China vendors. The technology is rather complex and our last attempt at employing US engineers to design a cost effective and reliable inverter totally failed to achieve anything near the cost effectiveness required by the marketplace.

Lastly, there is no mention of Vagabond having a 1900W effective output. It's ability to charge a high WS flash unit is about times as many WS per recycle second as the original Samilux 300W inverter, thus it is referred to as having a 900W effective charging capability. This number is rather nebulous and is dependent on the current liming characteristics. In the real world, Vagabond II can recycle a 2500WS Zeus pack in 9 seconds VS about 27 seconds for a typical current limited inverter (if you can find one).

Thank Luap :)

This is exactly what I was looking for. I will order myself a Vagabond 2 and enjoy the benefits of a product that is specifically designed to work with my AB Strobes. I will just have to trim my dependence on the use of modeling lamps (perhaps just turn a single model light on at any one time when initially setting up to verify lighting coverage and placement, then turn it off).

I completely understand what you are saying about the lack of manufacturing of inverters in North America. Some of the quality with off shore products is a big concern. My company has kitted every vehicle up with a battery and 2000 watt continuous rated pure sine inverter to power tools and work lights and reduce the need of generators. It beats gas powered generators hands down for the times we need access to 120VAC. We even kitted up a portable system for lighting the inside of buildings when power is not available. We looked at the quite a few different models. The wave form on most of them is far from perfect, and their cooling systems where often questionable. I can understand the difficulties that you face in finding a manufacturer to build your Vagabond.


Thanks for taking the time answer my questions,


Spyglass

Please excuse me... I do not have an electrical background so this might sound abit stupid.

If I were to use for example a lower power setting on the AB or WL would the above peak power draw still be approx. 16A? I assume that it does though peak draw time will be less as it only needs to energize capacitors for the power setting selected...?

Thanks - ml

I believe that is correct.... current magnitude stays at about 18 amps peak.

Yes, this is correct.