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Whats your electrical setup?

What is your electrical setup?


  • Total voters
    134

Av8rRob

Well Known Member
Not looking to start a war but just curious to what you have on your aircraft and if you fly IFR with it.
 
IBBS = Integrated Backup Battery System
Sold by https://www.tcwtech.com

Thanks.

So, my next question is, if your EFIS has an internal battery backup, you mount a handheld GPS in the panel that has a battery backup to backup the EFIS GPS, and you have a battery powered backup EFIS such as the Dynon Pocket Panel, why would you ever need an IBBS, backup battery, or backup alternator?

I guess I won't need to answer this poll.
 
Thanks.

So, my next question is, if your EFIS has an internal battery backup, you mount a handheld GPS in the panel that has a battery backup to backup the EFIS GPS, and you have a battery powered backup EFIS such as the Dynon Pocket Panel, why would you ever need an IBBS, backup battery, or backup alternator?

I guess I won't need to answer this poll.
Because my LSE ignition doesn't have a backup battery.
 
Because my LSE ignition doesn't have a backup battery.

Good answer!

However, if you only have one LSE, then there is no requirement to have a battery as a single mag should keep you in the air until you can land and sort things out.
 
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None of the above

I didn't vote because my option isn't listed. I have two batteries but both are not full sized. The second one only runs the second Electronic Ignition system. One alternator. VFR only.
 
Good answer!

However, if you only have one LSE, then there is no requirement to have a battery as a single mag should keep you in the air until you can land and sort things out.

I have TWO LSE's, and there is no REQUIREMENT to have an alternate electrical source. But doing so makes a lot of sense.

My plan is to add a standby alternator at next annual.
 
One battery and one alternator. Backup batteries on both of the Dynon Skyview EFIS. Backup batteries on the Stratus II / iPad. Lightspeed + old fashioned Magneto.

If I lose my alternator, my main battery (PC680) has enough juice to power everything long enough to get safely to the ground.

If I lose my main battery and alternator, I can still fly using my EFIS on battery backup to stay level, my Stratus to provide GPS, and my iPad / Foreflight to provide mapping.

If I lose my IFR GPS (an Avidyne IFD440), I can use my Dynon GPS.

If I lose my Dynon EFIS / Artificial Horizon Display, I can use my Stratus / Foreflight Artificial Horizon Display.

If SHTF, I figure I have about 45 minutes of battery to figure out where the ground is.

If it's VFR, I'll go do a couple more loops, two rolls, dance with a cloud, and then head back to the airport.
 
Good timing on this thread. I just now am thinking of converting my VFR only 7A to IFR. I've pretty much decided to go with a second full size battery each with redundant ways to deliver their power to any avionics that need it. I'm with DakotaHawk. If alt quits.... the dynon will have a separate battery.... the Garmin G5 will have an internal battery.... the ifly software on my tablet driven from a stratux receiver will provide a synthetic vision capability. That would be last resort. Remember there is two full size batteries to power the important stuff too. I think I would make it back to the planet with time to spare. I'm not one that would press on! Loss of the alt would prompt me to take action to get back to VFR weather or at the least below the clouds ASAP.
 
As I?ve offered in the past, I will send my dual PC-625 power scheme to anyone interested. Just PM me your email address.

Carl
 
1 battery, 1 alternator and I occasionally fly in IMC.

But have dual self powered P-Mags, dual Skyview, a D6, a Garmin Aera, an Android tablet and a handheld radio all with internal backup batteries. Probably electrical overkill to quickly get me on the ground.

23f2.jpg


Before you ask, yes I only have 1 engine. :rolleyes:
 
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As you design redundancy into your electrical systems, be very careful.

The more complexity you add, the more likely it is something will go wrong; either you didn't take something into account with your design, you take the wrong action when SHTF, or a part fails, rendering your entire electrical system useless.

The best system is one that requires no action by the pilot in the event of an electrical failure.

Remember, Bob K's most excellent electrical design book came out before EFIS's were popular or had internal backup batteries. I wonder what he would recommend today. (I haven't looked at his book in Iver 10 years.)

If you install any type of battery backup system, schedule battery replacements every "X" years.

If you have an E-buss or other type of backup system, practice with it and if it isn't what you need, change it.

Best of luck and be safe!
 
SNIP>>>

The best system is one that requires no action by the pilot in the event of an electrical failure.<<<<SNIP

Exactly correct.
Design Objective #1: Continued IFR flight (including comms and XPDR) following an element failure with no pilot action. Electrical failure is not the simple loss of the alternator as this does not result in the immediate loss of any of the panel. The more challenging single failure points are common connections (including grounds), solenoids, switches, the various diode schemes and such.
Design Objective #2: Restoration of the lost panel components following an element failure with minimal pilot action. That action not to impact flying the plane in IMC and factoring in a high pucker factor.

Carl

Carl
 
60 amp alternator, PC680, worst case 7.5 Ah alarm battery to give me 30 plus minutes of avionics buss to get out of the clouds. Diodes make it all work effortlessly.

And an alternator on the pmag, but I don?t count that really.
 
I've received Carl's schematic for dual batteries and he's reinforced to me via emails the importance of being able to get that power to the critical places with no to minimal pilot action. I absolutely agree with the previous post about making your system too complex. That in itself adds a degree of increased risk.

Here's my thinking. I'll have two batteries and one alt. If I have an alt failure, I would be notified of that by the Dynon EMS. If I confirm/agree with the EMS of an alt failure, all I have to do is flip the two switchs to get power from BOTH batteries directly to the avionics and turn off the master switch. Power from the batteries will be direct to the avionics with the only connections being 1. At the battery 2. The relay (power in and power out) 3. The avionics buss connection.

With the Dynon's back up battery and the built in G5 battery along with the two full size batteries up front, I feel this would give me best I can figure an absolute minimum of like 90 minutes to get back to VFR or below the clouds.

Discussion: Carl's stresses the importance of getting the power to the necessary equipment. I agree. That includes battery grounds. Each of my batteries will be grounded side by side to the airframe/engine block.
A thought on the relays that will be the only thing inline between the batt power and avionics buss. The connection for power in and power out of each relay from each battery to the buss. There is of course the wires running into the cockpit for the switch and switch to ground that could fail too.... as well as the switch itself. Here again, There is ANOTHER switch going through the other relay to provide power from the other battery directly to the buss. OK..... What are the odds of first an alt failure followed by a second failure of a relay/switch/wiring connection at the same time and if that WERE to happen, there is the second battery with the exact same setup to get power from that OTHER battery to the buss? Admittedly I'm just learning all this stuff and am speaking from probably the most inexperienced point of view on VAF.

Reviewing my own schematic, I see there's a single point of failure at the 25 amp pull breaker. If that did happened it would only make sense to turn off both "direct to" relay switches again and go back to the battery only side of master to get power to the avionics buss. I wonder if it would make sense to leave the batt side of master on from the beginning of the alt failure and turn on the two "direct" source switches. Of course this last would add the importance of sheding all unnecessary loads from the main. The advantage is now there are THREE ways power is getting from the batteries to the avionics buss.

Any thoughts are appreciated.
dny0cy.jpg
 
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Paul,

Good process, now take it a step further. Consider a fault on the avionics buss itself. You loose everything.

Run half of your panel on each battery by having two avionics busses. As you'll note in the material I sent you having four small 30 amp avionics relays provides option to have a normal and backup source of power for each avionics buss. Last step is to delete the avionics master switch you have that ties the avionics buss to the main buss.

On any electrical fault first immediate action is to open both master solenoids - this places panel power in the most reliable state. Once stable, then decide if you want to trouble shoot stuff or just fly the 2+ hours on the reserve electrical capacity and figure it out on the ground.

Carl
 
I didnt vote cause I'm not RV, but I'm fully Z14 architecture (some minor mods wrt switches) and a Mini-X with back up batt. I'll prob use an Ipad with FlyQ for non panel maps and planning etc. Gear list in my sig block. IFR.
 
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Thanks Carl. I'll have another look at your schematics. Sure appreciate your expert input. It helps us all.
 
I have TWO LSE's, and there is no REQUIREMENT to have an alternate electrical source. But doing so makes a lot of sense.

My plan is to add a standby alternator at next annual.

if you want the second alternator for redundancy for the airplane great, but for redundant power for the LSE i have kept it simple. a 5.5 amp/hr backup battery. two on/on switches power from each battery to the each end out to the LSE boxes on the center. down position is normal battery up is secondary battery. connect second battery to the bus through a diode and it stays charged.

bob burns
RV-4 N82RB
 
I voted 1 batt/ 2 alts but for clarity sake since the poll was very specific, I have a B&C 60 amp belt driven, primary alt, a PlanePower FS1-14 30amp gear driven backup alt on the vacuum pump pad and my batt is an Odyssey 925. My architecture is generally Bob Nuckolls with a primary and E-bus. Oh and I fly IFR.
 
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