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Crafting N112DR

Well Known Member
I want to run my avionics for a extended period of time to test different things. Can anyone suggest to me what you guys use for powering the RV-12iS with the earthX battery to keep the battery from running down. I have a Tecmate OptiMATE Lithium 4s 9.5A TM-275 Battery Charger but it will only charge the battery and not power the avionics long term.

Thanks.
 
I want to run my avionics for a extended period of time to test different things. Can anyone suggest to me what you guys use for powering the RV-12iS with the earthX battery to keep the battery from running down. I have a Tecmate OptiMATE Lithium 4s 9.5A TM-275 Battery Charger but it will only charge the battery and not power the avionics long term.

Thanks.

According to charger recommendations page on EarthX's site this 25A batter charger will charge and maintain the EarthX battery (but it won't reset it if it drains completely down). This is a combination GPU, charger and maintainer device.

We are building a 14 with a lot of avionics in it and my plan is to get one of these, cut the Piper plug off of it and hard wire the connector to the battery and extend it where I can get to it without removing the cowl.

While I haven't tested this yet, I did have a very similar unit that I used on my previous plane, a Cirrus SR22 with dual Garmin Perspective units, and it worked just fine. 25A should be more than enough to supply ground power supply to our airplanes.
 
Any 25 amp or above Switching Power Supply that you can adjust the voltage to 14.4V could be used.

http://www.megawattpowersupplies.com/

Down at the bottom, you can get a unit for $50. S-350-12 is the model. It provides good clean power, noise free, a lot of ham radio operators use them with their radios. Plenty good for your sensitive avionics.
 
Any 25 amp or above Switching Power Supply that you can adjust the voltage to 14.4V could be used.

http://www.megawattpowersupplies.com/

Down at the bottom, you can get a unit for $50. S-350-12 is the model. It provides good clean power, noise free, a lot of ham radio operators use them with their radios. Plenty good for your sensitive avionics.

My concern with a regular switching power supply with overcharging. Here are the requirements from EarthX's site. Does anyone know if a switching power supply would meet these requirements or not?

EarthX%20Requirements.jpg
 
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According to charger recommendations page on EarthX's site this 25A batter charger will charge and maintain the EarthX battery (but it won't reset it if it drains completely down). This is a combination GPU, charger and maintainer device.

We are building a 14 with a lot of avionics in it and my plan is to get one of these, cut the Piper plug off of it and hard wire the connector to the battery and extend it where I can get to it without removing the cowl.

While I haven't tested this yet, I did have a very similar unit that I used on my previous plane, a Cirrus SR22 with dual Garmin Perspective units, and it worked just fine. 25A should be more than enough to supply ground power supply to our airplanes.

Thanks for the recommendation I will look into it
 
My concern with a regular switching power supply with overcharging. Here are the requirements from EarthX's site. Does anyone know if a switching power supply would meet these requirements or not?

EarthX%20Requirements.jpg


You stated that you wanted to run your avionics for an extended period of time.


If that's what you want to do, then disconnect your battery and use the PSU. Non issue.

Or leave it connected, and adjust the PSU to 13.7V output instead of 14.4V.

If you want a battery charger, then buy a battery charger for your batteries specific chemistry. Most of the LiFePO4 batteries that I am familiar with have built in balancing charging for cells and cutoff circuitry. Look up Bioenno.
 
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I want to run my avionics for a extended period of time to test different things. Can anyone suggest to me what you guys use for powering the RV-12iS with the earthX battery to keep the battery from running down. I have a Tecmate OptiMATE Lithium 4s 9.5A TM-275 Battery Charger but it will only charge the battery and not power the avionics long term.

Thanks.

You already might have exactly what you need. The Optimate 4s 9.5A charger has a special battery support mode for tuning, diagnostics or to run systems. It only works if you are starting with at least 13.3volts. After hooking up battery to charger you press the "Tuning" button for 3 seconds unitl LED #1b and LED #6 light together. See your Optimate Manual top of Page 7 "Tune" for more information.

Jim
 
Is there something that can be used for extended avionics use that does not require a nearby 120 volt outlet, and does not require the plane?s battery to be disconnected?
 
You already might have exactly what you need. The Optimate 4s 9.5A charger has a special battery support mode for tuning, diagnostics or to run systems. It only works if you are starting with at least 13.3volts. After hooking up battery to charger you press the "Tuning" button for 3 seconds unitl LED #1b and LED #6 light together. See your Optimate Manual top of Page 7 "Tune" for more information.

Jim

I have tried that exact procedure and no joy.
 
Is there something that can be used for extended avionics use that does not require a nearby 120 volt outlet, and does not require the plane?s battery to be disconnected?

You could always buy an inexpensive lead-acid battery and charger and jumper the battery into your system.
 
You could always buy an inexpensive lead-acid battery and charger and jumper the battery into your system.

I did this a couple of months ago, and then had a battery-no-longer-charging problem, about which I started another thread here on vansairforce. Eventually -- with the help of others on vansairforce -- I determined that my problem was two-fold: a bad Ducati Rectifier/Regulator, and a blown fuse hidden and soldered inside the Switch & Fuse Module.

I now wonder whether my use of a jumpered battery to operate my avionics was the initial cause of my problem. This is what I speculate; if you disagree, please say so.

1. Even though I thought my external battery was well-charged, I suspect it wasn't as fully charged as the battery in my plane. Thus, instead of the external battery feeding the internal battery as I used the avionics, the internal battery was actually feeding the external battery and was losing voltage as a result.

2. When I next started the engine in order to fly, I suspect the internal battery was weak, and thus, the Ducati worked extra hard in order to power my avionics and recharge the plane's battery at the same time. That, I suspect, is what killed the Ducati.

3. While trouble-shooting the charging problem, I pulled and replaced the visible fuses, one at a time, to see whether one of my plane's components was drawing excessive amps. I also pulled and replaced my Dynon Wifi Adapters. In order to see the effect this had on amps, my Dynon had to be on, so my Master Switch was on. I suspect this may have been why the fuse that's hidden and soldered inside the Switch & Fuse Module blew.

Again, if this doesn't seem correct, please so.

But this is why I've been looking for something that can be charged at home and then attached to my plane's battery (I have pigtail wires attached to the battery) that will -- with certainty -- charge, rather than drain, my plane's battery.
 
If you connect the external battery across the one on in the plane, the voltages will try to equalize - the one with the higher voltage charging the one that is lower. Once they equalize, they will both try to equally power the load, but due to the inevitable difference in internal resistance between the two batteries, it's unlikely to be an exactly equal amount of current, but yes, the load will eventually pull the voltage down on both batteries.

To avoid this problem, you?d need to jumpier the external battery directly across the avionics bus and not switch on the master. This would isolate the internal battery so it won?t loose its charge.
 
. . .jumpier the external battery directly across the avionics bus and not switch on the master. This would isolate the internal battery so it won?t loose its charge.
Oh, now I understand. I didn?t build the plane; I bought it from the builder. He gave me the Kit Builder?s Manual. But I don?t find anything in it that explains how I would get to the avionics bus. My plane is a -12. Can you tell me how to connect the external battery to it?s avionics bus, or what manual I should look at to find out how to do it? Thanks.
 
My plane is a -12. Can you tell me how to connect the external battery to it?s avionics bus, or what manual I should look at to find out how to do it? Thanks.
P.S. Is it possible that my -12 doesn?t have an avionics bus? My plane has dual Dynon Skyview HDXs. And I?m wondering whether they might be wired directly to the plane?s battery via the Master switch.
 
The bus where all of the fuses are mounted is what I was referring to as the “avionics bus”. I built an iS so am not the one to give you advice regarding the best way to make the physical connection. I assume you’ve got a ULS. If so, I believe you have a 12-V auxiliary outlet, i.e. “cigarette lighter”. If so, and it is not connected directly to the battery, meaning it is only hot after the master is switched on, you could simply connect the external battery there. Get a fused cigarette lighter plug and simply plug it into the outlet. A 10-A fuse should be a good size. Make sure the wire used is 18 gauge or larger for a 10-A fuse. That would be the simplest way from my perspective.

And if you do pursue this option, make sure the fuse that is protecting the aux outlet is large enough to supply the avionics you intend to power from the external battery.
 
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The cigarette lighter is fused 5 amp (POWER OUTLET) on your switch/fuse module. It would not be wise to install a higher rated fuse and try to power your avionics through this circuit. Five amps will not support all the avionics.

Be careful. Responses to your issue on the forum are all trying to be helpful but some are based on experience with other RV's. The RV-12 is kind of a different animal. Van's knows the -12. Anything you are considering should be run by Van's tech support.
 
The cigarette lighter is fused 5 amp (POWER OUTLET) on your switch/fuse module. It would not be wise to install a higher rated fuse and try to power your avionics through this circuit. Five amps will not support all the avionics.

Be careful. Responses to your issue on the forum are all trying to be helpful but some are based on experience with other RV's. The RV-12 is kind of a different animal. Van's knows the -12. Anything you are considering should be run by Van's tech support.

Oh my. I have a simple and what I think is a common problem. I need to power the Dynons in a plane that?s in a tie-down space without a nearby 120 volt outlet. But the solution gets more difficult with every post.

According to the Dynon Skyview HDX Installation Manual (page 2-4), the HDX requires 2.4 amps, and the recommended circuit protection is 5 amps. So it looks to me that even if I try to power both of my Dynons at the same time through the cigarette lighter power outlet, I?ll need just 4.8 amps of current, and the 5 amp fuse for the power outlet will be sufficient. Is that right, or is there something I don?t understand?
 
Tony is right. If it?s only a 5 A circuit it?s too small. You need more margin. If you?re willing to remove the cowl top cover, you could disconnect the negative lead from the battery to isolate it and jumper the positive terminal of the external battery to the positive battery terminal of the aircraft battery and the negative lead of the external battery to either the aircraft frame or the negative lead that was disconnected. Then you?d then still power everything with the master switch.
 
Tony is right. If it?s only a 5 A circuit it?s too small. You need more margin. If you?re willing to remove the cowl top cover, you could disconnect the negative lead from the battery to isolate it and jumper the positive terminal of the external battery to the positive battery terminal of the aircraft battery and the negative lead of the external battery to either the aircraft frame or the negative lead that was disconnected. Then you?d then still power everything with the master switch.
And what if I used the cigarette lighter but only turned on one Dynon display at a time, and nothing else ? no lights, no radio, etc.? One Dynon would draw only 2.4 amps.
 
And what if I used the cigarette lighter but only turned on one Dynon display at a time, and nothing else ? no lights, no radio, etc.? One Dynon would draw only 2.4 amps.
Never mind. Sometimes I need both Dynons on at the same time, so if I can?t do that with a 5 amp fuse in the power outlet slot, and I can?t put a 7.5 or 10 amp fuse in that slot even temporarily, then I need another solution. Taking the top cowl off is possible, but it sure is a lot of work just to use the Dynons without running down the plane?s battery.
 
Thank you Joe, Bob and Tony. The schematic in the RV-12 POH shows that the cigarette lighter socket is not wired directly to the battery; it?s connected to the Main Bus, and thus the Master has to be on for the socket to get power. I?ll confirm that at my plane by using the cigarette lighter adapter plug for my handheld radio. If it checks out, I?ll put a 7.5 amp fuse in the Power Outlet slot which shouldn?t hurt anything because the EFIS fuse is 7.5 amps, and the Dynons are the only things I?ll be using with the external battery attached through the cigarette lighter.
 
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