Electrical System Design and Build

[leok]

A few people asked for the link to my Excel planning file that was not in the earlier link. This is the file I originally used to sort out different suppliers, switches, grouped functions etc..

Not as useful as the Power Point slides of the wiring diagram. However, they might be useful for someone in the thinking and planning stages working to get their arms around their own content

So here is the link:

https://drive.google.com/file/d/0BxZ...ew?usp=sharing

Also a second link to the Power Point file of wiring diagrams (since I now figured out how to use the Google One Drive I already had)

https://drive.google.com/file/d/0BxZ...ew?usp=sharing

Feel free to drop a line or even stop by if you are in Michigan in the future. We (My wife and I) are in the RV Hotel listing.

[444TX]

Nice work with lots of planning. There may be a few gotchas though.

1. BATTERY BUS (SWITCHED). If you are forced to shut of the master in flight you have no power to the bus and lose fuel pump and electronic ignition #1.

2. If switching the E-BUS switch from VPX to battery there may be a momentary open that would reset some of the avionics. If done in IFR or an emergency this would not be good. At least test for problems.

3. Might take the E-BUS backup power feed off the fuse and use the fuse box input stud with a fuse link. Would not use one fuse for so much important stuff. Have seen fuses melt and fuse connections get hot and distorted.

4. 7 SWITCHES. Three are down on and four are up on. The aircraft standard is all down for off and up for on. I see what you may be doing and it is you who is flying your design, but non standard can cause confusion issues when emergency decisions are made. Would recommend consistency.

5. I would remove the G5 from any external bus inputs to keep true independence. A single point failure could take out the entire set of Garmin flight instruments. I know that the Garmin experts say it can/will not happen, but do you want to bet your life on it flying IFR. True independent redundancy would be preferred.

A single large diagram of all the power circuits may find other small potential problem areas. A lot is riding on the VPX. Hope it is reliable and glitch free.

George

[tspear]

Here is a question I was asked this week, and I do not have a good answer.
I would like to use VPx, but in the last ten years they have had multiple model changes.
My next plane will be my last plane, and I hope to fly for thirty more years.
So, if you plan to fly for a long time, do you treat the VPx like your avionics and plan to replace it? Or do you abandon such advanced technology and go with simple single pole circuit breakers which have been the same for forty years and will likely still be the same in another forty?

Tim

[Carl Froehlich]

Originally Posted by tspear

Here is a question I was asked this week, and I do not have a good answer.
I would like to use VPx, but in the last ten years they have had multiple model changes.
My next plane will be my last plane, and I hope to fly for thirty more years.
So, if you plan to fly for a long time, do you treat the VPx like your avionics and plan to replace it? Or do you abandon such advanced technology and go with simple single pole circuit breakers which have been the same for forty years and will likely still be the same in another forty?

Tim

You already know the right answer - switches and breakers. Spend the saved money on avgas.

This will also eliminate the single point failure aspect of a VPX type box.

Carl

[PilotjohnS]

In my opinion, I am building a plane to take me places. I am trying to minimize anything having to do with software because I dont speak that language (pun intended). So If it doesnt make me faster, I am going old school with the exception of avionics. My electrical system is gonna be old school too, tried and true. So I guess your decision is based on what you want from the plane?

[tspear]

Originally Posted by Carl Froehlich

You already know the right answer - switches and breakers. Spend the saved money on avgas.

This will also eliminate the single point failure aspect of a VPX type box.

Carl

Originally Posted by PilotjohnS

In my opinion, I am building a plane to take me places. I am trying to minimize anything having to do with software because I dont speak that language (pun intended). So If it doesnt make me faster, I am going old school with the exception of avionics. My electrical system is gonna be old school too, tried and true. So I guess your decision is based on what you want from the plane?

Carl, John,

I am one of those software geeks
Here is the appeal for me on VPx:

• Remote management. Fewer wires through the firewall (in theory) and through the cabin (in theory).
• Less physical switches.
• Better monitoring and debug of electrical issues. You can monitor individual voltage, current or amps by circuit.
• "upgrade protection". I waffle on this one, easy to change the breaker rating if you change the end point device (e.g. from halogen to led light).

But I am now having second thoughts, and wondering if others had/have....

Tim

[Walt]

Originally Posted by Carl Froehlich

You already know the right answer - switches and breakers. Spend the saved money on avgas.

This will also eliminate the single point failure aspect of a VPX type box.

Carl

Let me just say that Carl and I agree on this one...

[rv7charlie]

Do you have a copy of Aeroelectric Connection? (hint, hint)

[PilotjohnS]

Now you got me thinking about a VPX. This could get expensive. Especially if you tell me the VPX sends data to the G3X over the CANbus.

[tspear]

Originally Posted by rv7charlie

Do you have a copy of Aeroelectric Connection? (hint, hint)

No, it is on to on the buy before I start list.
I have reviewed a few excerpts from others who have it.

Tim