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Old Sep 19, 2012, 06:53 PM
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Arngeir Blakseth's Avatar
Molde, Norway
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Why not simply try to run the fan yourself, then you'd find out how it performs. Much easier than getting a straight and true answer out of JD.
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Old Sep 20, 2012, 12:44 PM
Xtreme Power Systems
Lake Havasu, AZ
Joined Jun 2005
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You need the higher amperage controller because the power requirement is exponential. The amperage increases dramatically. 18S is closer to 240 amps (at 3.70v per cell using 70C batteries). The motor will handle 20Kw itself, but it is limited to 18S in voltage. The wind (and wire) would have to change in order to use more voltage and less amperage to achieve the same wattage. Make absolutely sure that you test your setup with a ballastics shield over the fan system in case there is a blade failure. Keep in mind the 3.7v per cell is from fully charged (4.2v), under full load, using 10,00mAh batteries. The more capacity you have the lower the voltage drop will be and the higher the wattage output. At this type of load, it doesn't take long to drop from 3.7v per cell to <3.0v per cell. So, you need to be careful not to destroy your packs. Don't expect long flight times at full throttle! For my Starfire setup, I need about 35 seconds of full throttle to make the two passes required and then some low throttle for take-off and landing.
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Last edited by JimDrew; Sep 20, 2012 at 12:54 PM.
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Old Sep 20, 2012, 07:11 PM
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Ballistic Shield?

What thickness plexiglass do I need?

20Kw PRO VERSION! Only $549 ready to install!

So I read this as the fan is now limited to 18S and on that it will pull 240 amps
this adds up to 15984 watts.

I do not see any way that this 20kW setup can run at 20kW if I understand all this. Yes I read the motor will handle 23kW before the windings break down but I read that we are limited to 18 cells so I am only 4000 watts short of 20kW

Do I get the picture?
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Old Sep 21, 2012, 04:55 AM
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Son, Norway
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xxS is not a good way to define max voltage for an application. Voltage will vary depending on current and cell IR (depends on C-rating, capacity and temperature). Only testing can tell if a battery will limit power to a safe level (<20kW).
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Old Sep 26, 2012, 11:33 AM
Xtreme Power Systems
Lake Havasu, AZ
Joined Jun 2005
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Quote:
Originally Posted by Air Head View Post
What thickness plexiglass do I need?

20Kw PRO VERSION! Only $549 ready to install!

So I read this as the fan is now limited to 18S and on that it will pull 240 amps
this adds up to 15984 watts.

I do not see any way that this 20kW setup can run at 20kW if I understand all this. Yes I read the motor will handle 23kW before the windings break down but I read that we are limited to 18 cells so I am only 4000 watts short of 20kW

Do I get the picture?
The fan system as always been limited to 18S. You can exceed 20Kw with the proper battery setup. If you could have only a .2v drop at full load, you would have 18x4.0 = 72 x 300A = 21600 watts.

The problem is that the voltage sags under load. If you used 50000mAh of capacity there would likely be very little sag.
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Old Sep 26, 2012, 12:05 PM
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Ill try it out Jim - Thanks

I am planning on using a 12,000 mAh battery, 50,000 would be a bit heavy. Is that how it was run at 20kW? Your spec list shows 16 cells @ 205 amps and then the jump to 18 cells is 300.

Picking up the controller after work today and almost finished with the test stand. (Update) (They sent the wrong controllers)

Thanks

Rick
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Last edited by Air Head; Sep 26, 2012 at 09:05 PM.
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Old Sep 26, 2012, 02:57 PM
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Is the current $549 fan the only available option right now?
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Old Sep 26, 2012, 06:20 PM
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Oh and if I were to purchase one what ESC are people running that works well? I saw talk on here of HV escs but I haven't seen anything on the XPS site.
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Old Sep 26, 2012, 09:09 PM
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what ESC are people running that works well

That would be the problem.

Id like to see this actually run up on 16 cells, and also the 20kW as advertised.
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Old Sep 27, 2012, 03:03 PM
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So what in the mean time? I see some running on ICE2 160 HV but I also see people talking about them burning up. Castle Cremations... you know.
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Old Sep 27, 2012, 05:59 PM
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I think I was wrong about them actually being in stock. Wasn't apparent from the site but someone posted they weren't in stock. Tried adding to cart and sure enough it said no inventory.

Soo......

JD any timetable?
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Old Sep 27, 2012, 06:41 PM
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Arngeir Blakseth's Avatar
Molde, Norway
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Jeti Spin 300, or a MGM Compro X-series 25063 will get you going on up to 15S, above that is a problem now that the Fightercat series of esc's seems to be gone, and XPS does not have their HV series out as promised.
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Old Sep 27, 2012, 07:15 PM
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I got the jeti spin 200 as a recommendation as well. 200 is probably good enough for me. I might be happy with 12S and if not perhaps 14 would be plenty. YA F18 is my target and I think it can come in under 16lbs when RTF. Those are all "coming soon" to on espritmodels though.

Is it just me or is the high end EDF market dwindling?
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Old Sep 27, 2012, 07:44 PM
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Controller Setting Questions

Anyone know the best settings for the controllers?

I am wondering about the PWM (8 / 16 / 32) - and Motor Timing.
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Old Sep 27, 2012, 11:27 PM
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Vancouver B.C.
Joined Apr 2002
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Why not just get BVM's new fan and controller. Bulletproof service should anything go wrong.....and they actually torture test their systems before being released to the public.

http://www.bvmjets.com/Pages/EVF3_12+.htm

I don't know what application Air Head is putting this fan in - but anything above 12S and about 8000 watts is rare and probably not needed for about 99.5 percent of the modelers out there.
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