Alexa powered through Zephyr sled? Answered.

[Mark Schlicher]

Revisited one of the threads again. http://www.steadicamforum.com/index.php?showtopic=12842&pid=68884&st=0entry68884

 

Distilled:

from Eric: 22ga max current handling 4.6A

from Jerry: Lemo 0B 303 panel connector 6A

from Jerry: 100W at 26V (below battery knee) current draw is 3.85A. At nominal 29.6V, 3.18A.

 

Eric's opinion: 22ga and 0B is insufficient at 100W.

Jerry's opinion: 18ga and 0B fine at 100W/24V (didn't speak directly to 22ga)

 

Left unanswered (but math above suggests it should work): 22ga and 0B at 24V sufficient? Note 22ga handles 4.6A, 26V/100W dras 3.85A.

 

Also: I've run Red Epic at 12V with two Dionic 90's successfully on long shoot days. The Epic is 65W/14.4V nominal, plus BFD receiver/Heden motor@ "35W maximum". This equates to the neighborhood of 7A.

 

In this "real-world" situation it worked fine, though the voltage drop did cause the Epic to shut down very prematurely when using crappy old rental house batteries. Mounting a pair of fresh Dionic 90's we got excellent battery life. Also, we had to power on the BFD receiver before the camera, otherwise the Epic would shut down from the momentary voltage sag.

[Eric Fletcher S.O.C.]

Revisited one of the threads again. http://www.steadicamforum.com/index.php?showtopic=12842&pid=68884&st=0entry68884

 

Distilled:

from Eric: 22ga max current handling 4.6A

from Jerry: Lemo 0B 303 panel connector 6A

from Jerry: 100W at 26V (below battery knee) current draw is 3.85A. At nominal 29.6V, 3.18A.

 

Eric's opinion: 22ga and 0B is insufficient at 100W.

Jerry's opinion: 18ga and 0B fine at 100W/24V (didn't speak directly to 22ga)

 

Left unanswered (but math above suggests it should work): 22ga and 0B at 24V sufficient? Note 22ga handles 4.6A, 26V/100W dras 3.85A.

 

Also: I've run Red Epic at 12V with two Dionic 90's successfully on long shoot days. The Epic is 65W/14.4V nominal, plus BFD receiver/Heden motor@ "35W maximum". This equates to the neighborhood of 7A.

 

In this "real-world" situation it worked fine, though the voltage drop did cause the Epic to shut down very prematurely when using crappy old rental house batteries. Mounting a pair of fresh Dionic 90's we got excellent battery life. Also, we had to power on the BFD receiver before the camera, otherwise the Epic would shut down from the momentary voltage sag.

 

 

Yes the connector can handle 6amps that's because it's bigger than the wire that goes into the solder pocket, you circuit is only as good as the weakest link. 4.6amp for 22 gauge wire is IN FREE AIR, not in a wire bundle where it is 2.3 amps.......

 

having to power any equipment down in order to start the camera and saying that it's ok is unacceptable if you think that using tools on set will get you fired having to run a power up checklist/procedure will get you fired faster

[Mark Schlicher]

Yes, I did use the calculator back in August.

 

I'm not asking to be "spoon-fed" anything. I wasn't asking about the calculator. I was asking about the mathematical and logical assumptions underlying your conclusion.

 

I was attempting to reconcile differing opinions about the design limits of a piece of gear I use. One from you, one from the manufacturer, one from Jerry.

 

To that end, I was asking for clarification about your basis for an opinion you expressed. I was not arguing with your opinion.

 

If you believe my questions are a request to be "spoon-fed", then PLEASE feel free to simply ignore them. Your condescension is uncalled-for.

 

Seriously.

[Eric Fletcher S.O.C.]

Yes, I did use the calculator back in August.

 

I'm not asking to be "spoon-fed" anything. I wasn't asking about the calculator. I was asking about the mathematical and logical assumptions underlying your conclusion.

 

I was attempting to reconcile differing opinions about the design limits of a piece of gear I use. One from you, one from the manufacturer, one from Jerry.

 

To that end, I was asking for clarification about your basis for an opinion you expressed. I was not arguing with your opinion.

 

Mark,

 

this has been discussed before, several times, links have been provided, those links included the math (which I have done many times) You have been arguing with me, you keep coming back to "I just flew an epic" That's great, you've made it apparent that as far as you're concerned the Zephyr is the greatest sled on the planet even though you do say that you've had some power issues and those issues are why 22ga has no reason being primary power in any rig. As for Jerrys answers he has never said that 22ga is appropriate for a high current camera, his answer speaks to 18ga and that is VERY different than 22ga (18ga has twice the ampacity of 22ga)

[RonBaldwin]

Ouch. My head.

[Nelson Villamil]

very interesting.

 

I like the Zephyr, within its range possibilities and limitations /

 

The caliber of the internal wiring of the Zephyr, I like to read more opinions and experiences of configurations used in the Zephyr.

 

Again, within its range ... which is considered the TOP in power consumption REAL.???

 

I like this debate

 

Thanks

[Mark Schlicher]

"you've made it apparent that as far as you're concerned the Zephyr is the greatest sled on the planet"

 

You have a funny way of putting words in my mouth.

 

 

Yes, I did use the calculator back in August.

 

I'm not asking to be "spoon-fed" anything. I wasn't asking about the calculator. I was asking about the mathematical and logical assumptions underlying your conclusion.

 

I was attempting to reconcile differing opinions about the design limits of a piece of gear I use. One from you, one from the manufacturer, one from Jerry.

 

To that end, I was asking for clarification about your basis for an opinion you expressed. I was not arguing with your opinion.

 

Mark,

 

this has been discussed before, several times, links have been provided, those links included the math (which I have done many times) You have been arguing with me, you keep coming back to "I just flew an epic" That's great, you've made it apparent that as far as you're concerned the Zephyr is the greatest sled on the planet even though you do say that you've had some power issues and those issues are why 22ga has no reason being primary power in any rig. As for Jerrys answers he has never said that 22ga is appropriate for a high current camera, his answer speaks to 18ga and that is VERY different than 22ga (18ga has twice the ampacity of 22ga)

[Robert Starling SOC]

I was attempting to reconcile differing opinions about the design limits of a piece of gear I use. One from you, one from the manufacturer, one from Jerry.

 

The manufacturer and Jerry are one in the same for all practical purposes. I'm not saying that's a bad thing... just saying that he has a close business relationship with them as the co-designer and maybe even the designer of certain products. He knows what he's putting in those rigs and what their target market is for a specific rig. I don't think the Zephyr was made for the Alexa level camera platforms on a daily basis.

 

Frankly, I don't know or care squat about wire gauging other than bigger is better, but in the world I work in I have to have the best available because I never know what camera and build is coming my way the next day.

 

If you're having issues on power-up you're clearly pushing the limits of your system, the factory may not warranty that if you burned out your wiring harness though Tiffen always took great care of me and my rigs.

 

It's the same thing running arms to their max all the time; those are upper limits the mfrs specify based on the springs, bearings and gimbals that in daily use will fail sooner rather than later. Always at the wrong time. My wife's SL55 AMG sports car purportedly goes 180+ mph and I'm sure it does but it would also wear out a lot faster if either of us had the balls to run it that fast every day. Well, at least I don't. I don't know what she does on her daily commute! :D

 

Enjoy your rig but know it's limitations and design intent else you'll risk a failure that could be costly financially and to your career.

 

Robert

[Mark Schlicher]

Agreed, Robert. Every rig has limits.... The Zephyr included.

 

I've been clear and vocal about the Zephyr's limits, from my very first posts about the rig. Anyone who claims that my position is something different is, erm... mistaken.

 

I appreciate your reasonable and respectful approach. Wish there was more of it on the forum.

 

"I don't think the Zephyr was made for the Alexa level camera platforms on a daily basis."

 

I completely agree, and I've said so on other threads. The Zephyr can handle some Alexa configurations but not others, and requires careful consideration of both power and weight...making it a much better fit for someone who owns their own Alexa or is in a position to have a large degree of control over how it is rigged up.

 

I turned down an Alexa gig just last week because of that reality. Does that make Zephyr the wrong rig for me? No. I made my choice with my eyes open and my desired market in mind. If I was in your market and your position it would absolutely be the wrong rig for me. No question.

 

That said, at 24V (nominal), and assuming a derated (enclosed) ampacity of 5A for 22AWG wire, that would allow the Zephyr to power up to roughly 120 watts of Alexa and accessories from the sled. At a more conservative 4A, 96 watts. Easy enough to rig a third battery for the monitor if necessary for more "headroom". Ideal? No. Perfectly fly-able? It would seem so. http://wiki.xtronics.com/index.php/Wire-Gauge_Ampacity

[bobgilles]

Hey everyone, I know this is a old conversation, but I have to tell you all that I fly the Alexa, BFD and Super Speed primes on the Zephyr often. It is totally doable and very smooth, it actually loads the arm perfectly and comes in at around 18lbs with the Teradek on top.