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Lights - standalone battery or piggyback?

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Lights - standalone battery or piggyback?

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Old 02-11-2019, 09:20 AM
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Auburn02
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Default Lights - standalone battery or piggyback?

With the overwhelming popularity of lights on current jets these days, curious how everyone powers them. My receiver batteries are typically WAY overkill (i.e. I have a pair of 2100 mah packs in my F-86, after 3 flights they might take 250-350 mAh each). So it doesn't make much sense to me to add yet another battery just to power some LED lights. But maybe I'm just not aware of how much a light system typically draws per flight?

My thought was to power the LEDs off of the receiver packs, could even run them from a Y harness to draw evenly from both packs in parallel. Any problems to doing this?

The next question is will they need to be independently switched. The controller will get its signal input from the receiver, but obviously if the batteries are run direct to the controller I suspect it will draw at least some power even with the receiver off, so is there any better way around that or stuck adding a switch?
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Old 02-11-2019, 09:40 AM
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gunradd
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I run them off receiver when I can. It seems like allot of the controllers call for 7.4 volts now and I don't use lipos so I end up getting a small battery just for lights if they need a lipo. If it works of LIFE batts I use receiver battery.

Yes you will need to either unplug or add a switch to keep power from drawing down.
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Old 02-11-2019, 12:10 PM
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Auburn02
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That makes sense Kris - the controller I have on hand does take 7.4V input, but on the bench at least I'm running it on a 6.6 and everything lights up fine so I'm still leaning towards that route for the time being.
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Old 02-11-2019, 01:30 PM
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I use turbine battery for lights as its 2S lipo and will never run out with lights only. And rx stuff keeps working if the worst happens.
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Old 02-11-2019, 01:41 PM
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The voltage to the LEDs has to be regulated somehow. The controllers output voltage needs to be regulated or there has to be a regulator circuit typically in each LED's harness. High quality controllers have a regulator. Low quality ones do not have a regulator and count on the regulator in each LED's harness. If your battery voltage exceeds the regulators' outputs, the right colors and intensity will be displayed. Best to take a volt meter and check the output of the controller and know what you have, especially if you are mixing and matching components versus getting a complete package with instructions. I have done Nav Lights both ways.

I have mine tied to the Rxer batteries. But, I have two 4000 mah batteries and could do a couple days worth of flights on them w/o charging. Never really bothered to calculate how many Mah is used by the lights. But, there is a significant amount of heat given off from each of them. So I imagine it is significant. High quality controllers only use a tiny bit of power when the Rxer/Controller is off. I pull the batteries after each weekend for charging anyway. So there is no need for a switch in my setup.

Be careful what you buy for Nav lights/systems. There is some real junk out there. There are also some high quality setups out there too. There are also different intensity levels available. So you want to shop around and do a lot of reading.

If you tie the batteries together, they should be matched up fairly well or tied via a coupler designed for that purpose (e.g. Bat-Share or PowerSafe, Powerbox, etc.) Vastly different internal resistances coupled together can cause serious issues (e.g. melted wire insulation = short = fire, unexpected low power situations, etc.) Kind of depends on the battery though. LiFes should run most LEDs. From my experience, … LiPos are designed to deliver higher voltage. they typically need voltage regulation and appear more sensitive to internal resistance issues. But LiPos appear more predictable as you get closer to their limit. But, then, LiFes are designed to deliver higher/more current. That's why you are seeing LiFes delivered with or recommended for a lot of turbines lately.

Just some thoughts. I frogged around with Nav Lights for weeks this year trying to get the OEM package to work correctly, trashing them and trying a piecemeal setup and then finally getting a quality package.
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Old 02-11-2019, 02:30 PM
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Thanks for that reply Len - out of curiosity after all of your research, which was the quality package you ended up with? I would say Unilight seems to have the most thorough offering out there from my limited research, but for my current project which is relatively simple in terms of light needs I went with a leftover Airpower setup from Dreamworks.
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Old 02-11-2019, 02:34 PM
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Unilight is good, a bit overpriced as its a niche product.
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Old 02-11-2019, 03:07 PM
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From my experience, the perfect light set kind of depends on what you want for lights. Barincubes are very bright and work well. But the landing light does not just come on when you drop the gear. You have to switch it on. Also, their LEDs area bit more directional that I would like. But if you put them under lenses then they look good and don't seem to be hot enough to melt the lenses. The JPs I had from the OEM were a mess. Never did get them to work correctly, but their landing light setup worked off the gear channel. That worked well. ElectroDynamics stuff I tried was a bit too low of intensity. But their stuff works as advertised and the support to get you there is great. So, … For me the jury is still out on the best brand. But again, it depends on what you want to do with lights. I have learned enough with all my trials and tribulations that my next set will probably be piecemeal based on a great controller. I say this cause there are some ultrabright LEDs out there that have a wide viewing angle and they do not get very hot. I tested several of them. You just have to figure out the correct voltages to get the right colors and keep them working. That is easy enough. But, it is the great controller that still eludes me. So, … I am not the expert. Some input from other folks is welcomed!
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Old 02-11-2019, 04:19 PM
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I guess I am the outlier here. I have a separate 4s NiCd pack to power my lights.I need nose weight anyhow and I like using batteries rather than lead. So I end up with one 3500mah 2s LiPo ECU battery, one 600mah NiCd lights battery, and two 3500 LiPo Rx batteries. I can keep it plugged in all the time. the controller turns the lights on and off when the Rx is powered up. The landing light only comes on when the gear are down. I cycle my batteries once a month during the winter and the lights battery is never low even being plugged in for a month. That 600mah pack will keep the lights on for about 10 hours continuous when the jet is on display at a show.
It is easy to test your light controller to see if it draws any power when turned off.
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Old 02-12-2019, 12:05 PM
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I usually run 2s lipos so I just piggy back it. Unilight 8 channel controllers (and their lights too!) are my undisputed favorites!
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Old 02-12-2019, 03:46 PM
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I've been running my smoke pump and nav lights off the reciever pack for years without issue.
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Old 02-13-2019, 09:41 AM
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Run off the RX batteries. Having to recharge light battery on top of RX batteries is a PINA IMHO. lol. All of the new BVM jets use the RX batteries to power everything and it works flawlessly.
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