R

ron sterba

Well Known Member
Its that time to wire up the panel. Have a 16 position fuse holder. (ATC type auto) Its split into 10 positions on first set of fuse holders and 6 on the other set of fuses.

I have a Dynon 10" and 7" skyviews., One com radio,Garmin GRT200, Pitot heat, defroster fan, boost pump, nav, strobe, taxi, landing lights, flaps, transponder,ADS-B unit.. I need a 60 amp breaker or fuse that can go either by starter relay or a breaker by ignition switch.,

I'am open for your thoughts. Always much appreciated!
Ron in Oregon
 
Opinions will vary with this one.
This is what I did but will be somewhat different than yours due to me running Dual Garmin G3X.
I consider the E-Buss as a quick save my -ss load shedding feature in an emergency. I only have to turn off one switch, the main and then I am on the E-Buss since that switch is already on.
In less of an emergency I can load shed individual components with their knobs and switches but I don't want to spend time doing that in a real emergency.
So my E-Buss is emergency use only.
PFD (MFD is on the main buss)
Avionics pieces to keep the PFD running (AHARS, magnetometer and engine module.
ELT
Xpndr
P-MAGS
GTN650 com, nav and GPS

I also have a IBBS for when the E-Buss goes dark and a Dynon D6 with internal battery.

Hope that helps.
 
I also don't know how you will get away with only 16 fuse positions.
I have a
(6) Battery Buss 4 - used
(6) E-Buss 6 - used
(16) Main Buss 16 - used

The E and Main are full.
 
You'll need around 30 fused runs. The difference between normal and emergency is the ability to shed loads. Nothing fancy. Everything should have its own power switch. A lot of our "modern" avionics abandoned this important feature.

Consider a battery buss hot wired to the battery so you can shut off the current-sucking master contactor that supports most loads through a main buss. On the battery buss are things that start and keep the engine running (with the exception of the starter contactor on the main buss - don't like surprises!); e.g., electronic ignitions, boost pump, maybe a few cockpit LEDS. Just keep in mind the more you put on the battery buss, the more diligence needed to assure everything is indeed off before you go home.

John Siebold
 
I'm very similar to MarkW ... main bus (16), E-bus (10), battery bus (6). In accordance with Nuckolls' philosophy, the E-bus has just the critical items I want/need to get to an airport (ideally my intended destination). That would include both EFIS displays, EIS4000, SL-30, audio panel, x-ponder, and similar. Since the E-bus has limited ampacity, heavier loads stay on the main bus (e.g. strobes, flaps, etc.)
 
Rupester said:
I'm very similar to MarkW ... main bus (16), E-bus (10), battery bus (6). In accordance with Nuckolls' philosophy, the E-bus has just the critical items I want/need to get to an airport (ideally my intended destination). That would include both EFIS displays, EIS4000, SL-30, audio panel, x-ponder, and similar. Since the E-bus has limited ampacity, heavier loads stay on the main bus (e.g. strobes, flaps, etc.)
Click to expand...
Hello Marks,John and Terry! In this distribution I can't see how you would use more fused items. Sounds like I missed some items to fuse. I have listed only 14 items that I think need fusing. Maybe you all have more radios than me. Now, I maybe missing something here. I just started reading Aero Electric but can't figure why 25-30 fused items would be needed? Are you doubled fusing off two different busses? As I dig deeper into my manuals (just skimming top now) on the Dynon Skyviews it was my impression that my one power feed to the EFIS supplied power to the servos and AHARS. My audio panel is built into the Garmin radio. My ELT has a battery, I don't know if I will have to supply power to it. So at this point based on actual wiring you folks have done I would load my busses as:
MAIN: Six positions
1- Boost pump
2- Nav lights
3- Strobes
4- Taxi
5- Landing
6- Flaps

Endurance 10 positions
1- Skyview 10"
2- Skyview 7"
3- Transponder
4- Ahars
5- Defroster Fan
6- Pitot heat
7- GRT200 Com Radio
8- Engine monitor


? My main buss will be fed off the master relay
? my endurance buss would be fed from two ways.
Alternator feed and a battery feed
Alternator feed would have Shoutsky diode preventing back voltage into alternator thus feeding off the battery MASTER Switch. (Split master switch just like the one in our Cessna 172, Since I have the split switch BATT/ALTERNATOR would I still need a diode? Bear with me I feel I'm in a overcast to broken layer looking for a block altitude higher to get out of the soup!

My mags are NOT electronic. May add panel lights too. It was mentioned about a third buss and so did the prints in the back of Bobs book and thought that maybe this is for people with electronic mags.Weigh in if this is ok to your thinking and guidance. Trying to manifest the the big picture based on plumbing diagram. If you want to use that water analogy that would be GREAT! Since my whole home was re-plumbed. I know of every valve and elbow, sinks, outside faucets, and lawn & garden sprinkler system.

Thanks Guys.
Ron in Oregon
RV9A EAA 292 Independence Oregon
 
I pretty much followed the Bob Nuckolls Z-11 schematic which has an endurance bus. The power diode in this schematic supplies power to the E-bus from the main bus without needing to turn the E-bus on. I can't remember why he thought that was better then just always turning on the E-bus switch in addition to the master. It seems like he mentions that this was an area which was subject to different opinions with each side of the argument having equally valid points.

I have two 12 circuit fuse blocks and every slot is used. But then nearly every circuit has its own fuse. I have two radios, an audio panel and a separate autopilot in addition to what you list. I also have a separate fuse for the starter and for the alternator field, and I think the Van's capacitive senders have a fuse.

Make sure your radio doesn't have two fuse requirements. The 430W has a separate transmit 10 Amp fuse in addition to the main 12V supply.
You didn't list any circuits for 12V aux power (cigar lighter receptacles).
And I guess you have manual elevator trim?
Interior lighting?

If you have backup batteries for your SkyViews, then you should put the SkyViews on the main bus.

One thing I did was put the flaps on the E-bus. This lets me put flaps down without needing to boot up the SkyViews, which are on the main bus. But the real purpose is allowing use of the flaps when on the endurance bus. Similarly, electric trim is on the E-bus.

My ELT requires a very low current supply to drive an LED on the instrument panel. I feed this from the battery bus.
 
Thanks Chip. Ill have to check the com radio when I get out to the hangar tonite. No interior lights at this point and have manual trim. Ill look at Z-11. I missed one item,I think, manifold pressure unit. Cigar lighter i thought would be a direct in-fuse to the battery bus. i'll put something to work here after the reading a little more and the ideas you builders have posted. Getting a better idea for my design for my circuits. I'll post tomorrow about 7:30 PM PST

Thanks everybody!
This looks to be a great thread.
Ron in Oregon
 
Well I know its not 7:30pm yet, but I have to say you guys who have sent me info to my email.You all have the Bob Nuckolls books in hand. Terry thanks for the thoughts to consider in designing my busses and why. For the MOST part those items will stay on those busses mentioned . That was much appreciated. Bob in his book explains both sides of the thought process to wiring. For me having the book with just skimming it doesn't cut it. I feel sorta embarrassed I asked the question first before really reading the chapters one by one. The Book is AeroElectric Connection 12th edition 2009 ) In the back you'll find schematics of variations of design. For me it looked like a highway for ants and their hangouts. If you pull it into perspectives either analogy, ants trails or better yet water system like your house. Starting with your city's water supply to your house and then into your house. I would like to add, i'll be adding a battery buss also. Just a few items to that battery buss, panel lights and cigar lighter. Based on several builders i asked about circuits mine is a easy one! There's heated seats and a bunch more possibilities.In Bobs book i was advised to look at the Z-11 schematic for a generic plan. Also you'll find schematics for two alternators one battery, or visa-versa, Rotex engine, electronic fuel injection just to name a few. I think B & C aircraft supplies has the book for sale but offers are found in many aviation catalogs. Check amazon.

I thank you all for helping me! I'll keep in touch. My EAA chapter said I'll be flying by June. Hope their RIGHT!

Ron in Oregon
 
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