How much?

Wade,

Any idea on the cost of these? I tried several of the distributor links from Nova's site, and none of them seemed to have the X1100 or prices.

thanks,
greg
 
grjtucson said:
...but expensive. $143.99 each for the clear ones:
Click to expand...

Not that expensive when you consider you don't need to buy a strobe power supply. Also, there is some weights savings when you consider you don't have to run heavy strobe wire to the wingtips.
 
Yeah $143 is the cheapest I have found.

I am going with them because, you don't need a strobe power supply, LEDs "should" never need replacement, you can select the flash pattern, and they are twice as bright as the quickstrobes with tubes (from Nova tech suppport; 12 watt flash tube puts out 40 lumens per watt "real world" which would be 480+ lumens, where as the LED is 1100 lumens).
 
Just curious if a white strobe on the tail satisfies the requirement for a white nav light on the tail.

Thanks!
 
FlyGuy said:
Just curious if a white strobe on the tail satisfies the requirement for a white nav light on the tail.

Thanks!
Click to expand...

The nav position lights on the tail (white) and wingtips (red and green) are required to burn continuously, not flash. If the LED strobe would have the ability to burn continuously at a reduced brightness to satisfy that nav requirement plus flash from dim to full brightness to accomplish the anti-collision strobe requirement, that would be interesting indeed.
 
Specs...

Does anyone know how close - or how many - these strobes come to meeting the FAA anti-collision requirements?

http://www.flightsimaviation.com/data/FARS/part_23-1401.html

I couldn't even find a light distribution curve on the Nova web site.

My initial guess is that the 1100 lumens doesn't cut it if the spread is large, and the bias may not be sufficient on the horizontal plane...:confused:

gil A
 
Seperate Nav and strobe

This sounds made to order?

In order to be bright enough would you need a seperate constant Nav and then a seperate white strobe or would a single split color red/white version meet brightness requirements?

Also what do you think folks think about potential powersupply whine?
 
Just by looking at the picture of the device, it appears the illumination pattern is somewhat directional. They might be fine for the wing tips, but maybe not the tail. Don't know.
 
Bugsy said:
This sounds made to order?

In order to be bright enough would you need a seperate constant Nav and then a seperate white strobe or would a single split color red/white version meet brightness requirements?

Also what do you think folks think about potential powersupply whine?
Click to expand...

True LED lights should not whine - the whine from a strobe is the high-frequency cycling of the high voltage power supply. LED's operate off ship voltage.
 
This appears to be the second generation of LED strobes from Nova. The first had a more limited coverage area, but this looks to do the trick. I bet they would fit in the standard Van's wingtips just fine.

However, what to do for the tail?

TODR
 
Gil
Good questions, and since you asked here are the output angles as mailed to me by Nova tech support. I also asked what the visual perception as in actually seeing and he said the LED was much brighter, yes hearsay and personal objectivity but it is all I have to go on at the moment.






I prefer having individual power supplies and the LEDs are an upgrade over the quickstrobes IMHO, so that is why I am getting them. Also the lighter smaller wire and 1.25 A each is another plus.

The only drawback as I see it now, is the built-in heatsink. It can be bent to accomodate, but that makes it unsuitable for a rudder application. But the price is about the same as the Kuntzleman tail LED light/strobe and quickstrobe power supply. Which is what I am going to use for my tail.



az_gila said:
Does anyone know how close - or how many - these strobes come to meeting the FAA anti-collision requirements?

http://www.flightsimaviation.com/data/FARS/part_23-1401.html

I couldn't even find a light distribution curve on the Nova web site.

My initial guess is that the 1100 lumens doesn't cut it if the spread is large, and the bias may not be sufficient on the horizontal plane...:confused:

gil A
Click to expand...
 
Last edited:
LED drivers may be DC-to-Dc converters

airguy said:
True LED lights should not whine - the whine from a strobe is the high-frequency cycling of the high voltage power supply. LED's operate off ship voltage.
Click to expand...

In fact, LEDs cannot operate off of ship voltage, unless it is a very narrow range. For this light, input current is specified to be roughly inversely proportional to input voltage. That virtually always means a DC-to-DC converter is used. In that case the switching frequency may cause "whine" or some interference with radios, depending on some details of the design.

Strobes are tremendously brighter than LEDs, but for a tremendously shorter period. The LEDs may be perceived as brighter because of the human eye response time. The maximum integration period specified by the FAA (don't have number at work) is too short in my opinion, and favors HV strobes with their short bright flashes.

This is what has kept me from installing LED strobes up till now. The fact that Whelen started providing them may be they are ignoring the letter of the law and going with what works.
 
mansboat said:
In fact, LEDs cannot operate off of ship voltage, unless it is a very narrow range. For this light, input current is specified to be roughly inversely proportional to input voltage. That virtually always means a DC-to-DC converter is used. In that case the switching frequency may cause "whine" or some interference with radios, depending on some details of the design.
Click to expand...

True - but it is a rare device indeed that uses a SWITCHING power supply (source of the whine) to drop voltage from ship voltage to the lower supply voltage that the LED's will actually be using. A simple voltage regulator or even a resistive element in series with the LED is much more common - neither of which will create any whine feedback. Switching power supplies are a near-requirement for increasing ship voltage to a higher output - but it's a simple trick to decrease it to a lower output.
 
Lacking in actual details...

RV8RIVETER said:
Gil
Good questions, and since you asked here are the output angles as mailed to me by Nova tech support. I also asked what the visual perception as in actually seeing and he said the LED was much brighter, yes hearsay and personal objectivity but it is all I have to go on at the moment.
........
Click to expand...

Wade... is that all you got?

I'm guessing that is a cone for each of the three LED planes to the 50% drop off mark.

A true beam dispersion diagram of output vs. angle would be much more appropriate in our aviation market... and to the FAA requirements.

gil A
 
Yes Gil, I am afraid that is all that I was sent, I know it wasn't everything you were looking for but thought I would share. Feel free to call or email Nova tech support and ask for whatever doc's you want.

Once I get mine and fire them up I will be happy to share my impressions, for what it is worth.:)



az_gila said:
Wade... is that all you got?

I'm guessing that is a cone for each of the three LED planes to the 50% drop off mark.

A true beam dispersion diagram of output vs. angle would be much more appropriate in our aviation market... and to the FAA requirements.

gil A
Click to expand...
 
DC-to-DC not rare at all

airguy said:
True - but it is a rare device indeed that uses a SWITCHING power supply (source of the whine) to drop voltage from ship voltage to the lower supply voltage that the LED's will actually be using. A simple voltage regulator or even a resistive element in series with the LED is much more common - neither of which will create any whine feedback. Switching power supplies are a near-requirement for increasing ship voltage to a higher output - but it's a simple trick to decrease it to a lower output.
Click to expand...

Airguy,
Dropping voltage is simple, but not at all rare to do with DC-to-DC for high power LEDs. The decision of resistive, verses linear, verses switching regulation has to do with several factors. If the LED is relatively high power (these are) and must operate at 12V & 24V (these do), then a switching regulator is the easy winner.
You missed the key clue I listed in my post: For the product under discussion, the input current decreases as a function of increasing voltage.

Input Current .......1.25 Amps @ 12.8V.......0.6 Amps @ 25.6V

In fact, apparently, the power supply is a little more efficient at higher voltage since the power drops. I'm changing my assertion from likely a switcher to definitely a switcher.

If it were done with a resistor, the current would roughly double from 12V-to-24V. Power consumed would be roughly 4x. Its actually a little worse than this, but either way its not very attractive.
If it were done with a linear regulator (voltage or current), the input current would stay the same over voltage. Therefore, the power consumption would double.
Resisters and linear regulators are virtually two sides of the same coin. They drop voltage or limit current by turning electrical energy into thermal energy.
DC-to-DC switch mode power supplies are POWER CONVERTERS. They use reactive elements (inductors and capacitors) to store electrical energy supplied at one voltage, then release it to the output at another voltage level (either higher or lower). Except for imperfections in switches, inductors, capacitors, etc, this is not a power dissipating process. Power remains constant (minus losses of course), so increasing the input voltage WILL result in a decrease in input current.
 
Steve Brown said:
Airguy,
Dropping voltage is simple, but not at all rare to do with DC-to-DC for high power LEDs. The decision of resistive, verses linear, verses switching regulation has to do with several factors. If the LED is relatively high power (these are) and must operate at 12V & 24V (these do), then a switching regulator is the easy winner.
You missed the key clue I listed in my post: For the product under discussion, the input current decreases as a function of increasing voltage.

Input Current .......1.25 Amps @ 12.8V.......0.6 Amps @ 25.6V

In fact, apparently, the power supply is a little more efficient at higher voltage since the power drops. I'm changing my assertion from likely a switcher to definitely a switcher.

If it were done with a resistor, the current would roughly double from 12V-to-24V. Power consumed would be roughly 4x. Its actually a little worse than this, but either way its not very attractive.
If it were done with a linear regulator (voltage or current), the input current would stay the same over voltage. Therefore, the power consumption would double.
Resisters and linear regulators are virtually two sides of the same coin. They drop voltage or limit current by turning electrical energy into thermal energy.
DC-to-DC switch mode power supplies are POWER CONVERTERS. They use reactive elements (inductors and capacitors) to store electrical energy supplied at one voltage, then release it to the output at another voltage level (either higher or lower). Except for imperfections in switches, inductors, capacitors, etc, this is not a power dissipating process. Power remains constant (minus losses of course), so increasing the input voltage WILL result in a decrease in input current.
Click to expand...

Steve,

You're right of course - I missed the current draw at 25.6 volts and wasn't looking at it from that side. There is no arguing with the energy conversion factors - I've got enough EE background to know when I'm wrong, and I'll admit it and shut up now! :D

We now return you to your regularly scheduled topic...
 
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