Paul C. Buff, Inc. Technical Forum

What would be the effect on recycle time and battery life if I load the VML with two Einsteins vs one at the same watt seconds ?

For example...

Setup #1
1 Einstein at 640WS

Setup#2
2 Einsteins at 320WS

Theoretically the load that the inverter sees should be identical except for additional capacitance of the cables, LCD panel backlights, and fans. I'm assuming there would be neglible difference to recycle time and battery life. However, I was wondering if there were any users who can confirm this ?

You have pretty much hit the nail on the head.

Thanks for the reply. Would pulling current through both sockets simultaneously be any different than pulling the current through a single socket ? I'm not sure how the inverter is setup but I'm just wondering if there is lower resistance when pulling current through two sockets leading to more voltage drop ?

Two units will draw twice as much current for half the time. This will cause a deeper brown out, but both the VML and the Einstein (or AB/WL) can tolerate this . . . even two Elinchrom RX600 units can, and would behave the same.

We have tested VML with five ABs at full power without problems. You may see around a 5-10% cycle time increase with two 1/2 power Einsteins vs one at full power.

So far, with over 5000 VMLs in the field we have yet to see an inverter or battery failure . . . they're pretty bulletproof with a remarkable reliability record.

Thanks for the info. I received my VML yesterday but haven't had a chance to mess with it yet. I was contemplating getting one VML for each Einstein but would like to keep the weight as low as possible for my location kit. If the cycle time penalty if only around 5 - 10% for using a single VML I think I can live with that. It's getting harder to meet airline carry on weight restrictions these days.

Don't misunderstand my explanation. Two Einsteins at the same power setting will take twice as long to recycle as two Einsteins on separate Vagabond Minis, and will provide half the number of shots per battery charge. Most power users opt to use one VML per light if they need minimum cycle times and maximum number of shots.