VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #81  
Old 05-15-2018, 10:01 PM
svyolo svyolo is offline
 
Join Date: Oct 2017
Location: bellingham, wa
Posts: 76
Default

Mark33;
I questioned (mostly silently) the oil pressure switch shutoff as another mode of failure. However your #4 answer, about this ONLY being active with normal operation of FP #1, and disabled with FP #2. I need to think about it a bit more, but I think I like it.

I am using a "severe service vehicle" fuse and relay panel that uses STDP relays. When I turn the key to "on", the battery contractor energizes and puts 12v to the panel. 87a is used for all normal functions. So no other relay other than the battery contactor needs to function. Switches are provided to switch to turn off FP 1 and 2, ign 1 and 2, and VR 1 and 2. Normal functions are all 87a. Shutting off the primary, and activating the secondary, are on terminal 87.

Carbs vs MFI vs EFI? I won't go in depth as it seems almost religious or political. Between MFI and EFI? The only thing I will say is that if you are using electronic ignition, you are ALREADY using the same primary sensors that the EFI uses. You are just powering a FP and injectors in addition to the coils and spark plugs. A couple of dozen extra wires, and a few electrons. If you are already trusting your warm body to EI, why not go all in and go EFI? Far fewer mechanical moving parts to wear, rebuild, fail.
Reply With Quote
  #82  
Old 05-15-2018, 10:09 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 4,395
Default

Quote:
Originally Posted by Carl Froehlich View Post
Don't forget the EFII crank sensor is itself a moving part.
The crank sensor is very firmly bolted to the engine case. I can assure you it doesn't move.





Only the magnets embedded in the flywheel move and they can't go anywhere nor is there anything to go wrong with them since they just sit there. No bearings, no rubbing or meshing parts like mags which is why no inspections are required.

Obviously many people see value in EFI or we wouldn't be in business. If your personal preference is mags and a servo with a bunch of moving and wearing parts, that's fine. I always say use what you're comfortable with. Many people do not have the same experience as you with their Bendix style injection and are looking for something to fix their issues.

The topic though is electrical system layouts for EFI, not EFI vs legacy controls.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, Marcotte M-300, IVO, RV6A C-GVZX flying from CYBW since 2003- 420 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi.htm



Last edited by rv6ejguy : 05-15-2018 at 10:15 PM.
Reply With Quote
  #83  
Old 05-16-2018, 06:15 AM
DanH's Avatar
DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
Posts: 7,539
Default

Quote:
Originally Posted by rv6ejguy View Post
The topic though is electrical system layouts for EFI, not EFI vs legacy controls.
Yes, please, let's return to topic.
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
  #84  
Old 05-16-2018, 07:37 AM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 1,388
Default

Quote:
Originally Posted by DanH View Post
Yes, please, let's return to topic.
Sorry I drifted from the topic.

Directly responding to electrical distribution, the examples so far discussed in this thread, in my opinion, fall short of what is reasonably possible if the builder wants simplicity, reliably and backup modes when something fails.

For those interested, PM me your email address and Iíll provide some ideas.

Carl
Reply With Quote
  #85  
Old 05-16-2018, 01:24 PM
DanH's Avatar
DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
Posts: 7,539
Default

Ok, so returning to guidance from an experienced vendor....

Quote:
Originally Posted by rcpaisley View Post
As far as I know:
1. Voltage regulator failure leading to over voltage, dual lithium battery installation melt down, electrical system failure.

2. Non standard wiring installation, too small of a circuit breaker used on the injector circuit, injector breaker popped during low level (river following flight), hard landing.
Robert
Thank you. So what can you help us learn?

RV-6: Voltage regulator failure is pretty obvious, based on the pilot report of hot batteries and 15.5V at last check. We've been told EarthX batteries disconnect from charging at around 16.5 volts (but still have an output, however strange that may seem). Let's assume both batteries disconnected at 16.5V, a fair assumption because a meltdown wouldn't happen until failure of the battery management system at 60V or more. How would a battery charging disconnect result in an "electrical system failure" which would kill an EFI/EI? And of course, how might it be prevented?

Airborne Extreme: If I understand correctly, you're saying there was only one circuit breaker for all injectors. There is no standard wiring diagram in the EFII-brand manual. What do you recommend?
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
  #86  
Old 05-16-2018, 02:07 PM
Pukauma Pukauma is offline
 
Join Date: Jul 2014
Location: West Covina, Ca
Posts: 44
Default Back to power architecture!

Glad this is heading back to the OP question!

So I include my latest electrical power architecture scheme. My goal is to be as SIMPLE as possible, with the least number of switches/relays/components. Not a lot of detail here, just concept.

This also stays in line with emergency procedures, as in masters off will not kill the engine. (hopefully we are still flying).



This is actually very close to MOD 2 of the original post. I think it has a lot of merit. One bugaboo I have is finding milspec highly rated switches to control the engine bus. Worst case scenario would be around 20amps, would like to be able to de-rate the switch a bit. (and locking would be very preferred). Any ideas?

Now I will sit back and wait to be flogged.....
__________________
Cliff Langlois
West Covina, CA
Cliffsrv10.blogspot.com

RV-10
Empennage finished!
QB Fuselage and wings in hand
Taking a bite of the elephant every day.
Dues paid-grateful
Reply With Quote
  #87  
Old 05-16-2018, 03:14 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 4,395
Default

I like Cliff's layout here and I'll have some links for some high current rated Mil Spec switches to post on here tomorrow hopefully.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, Marcotte M-300, IVO, RV6A C-GVZX flying from CYBW since 2003- 420 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi.htm


Reply With Quote
  #88  
Old 05-16-2018, 03:32 PM
Mike S's Avatar
Mike S Mike S is offline
Senior Curmudgeon
 
Join Date: Sep 2005
Location: Dayton Airpark, NV A34
Posts: 14,028
Default

Quote:
Originally Posted by Pukauma View Post
One bugaboo I have is finding milspec highly rated switches to control the engine bus. Worst case scenario would be around 20amps, Any ideas?
I used a switch rated at 20A, double pole and tied the two sides together----In theory this will double the load capacity of the switch.

Worked just fine for me.


All in all your setup looks good. One question......In your diagram is one of the busses carrying essential loads like nav or com equipment? If so, you could tie the two busses together with a diode to provide power from either battery automatically, should one power source take a little nap.
__________________
Mike Starkey
VAF 909

Rv-10, N210LM.

Flying as of 12/4/2010

Phase 1 done, 2/4/2011

Sold after 240+ wonderful hours of flight.

"Flying the airplane is more important than radioing your plight to a person on the ground incapable of understanding or doing anything about it."

Last edited by Mike S : 05-17-2018 at 05:51 PM.
Reply With Quote
  #89  
Old 05-16-2018, 06:18 PM
johnbright's Avatar
johnbright johnbright is offline
 
Join Date: Aug 2010
Location: Newport News, Va
Posts: 171
Default "Oh ****" switch

Quote:
Originally Posted by DanH View Post
A good design has no "Oh ****" switch to keep the engine running. Engine electronics need dual power or auto switching.

The airplane is at 200 feet, the departure end just went under the wing, and the engine quits. Right then, nobody has enough spare brainpower to diagnose an electrical problem.
Sorry to state the obvious but one "Oh ****" switch that's always there is the injector ECU select switch if you have dual ECUs. You already have a robust electric power system, both fuel pumps are running, and you located and perhaps also guarded the mixture knob so it won't be accidentally bumped. Flip the injector ECU select switch and check your fuel selector while looking to land. Perfection is a goal we of course will not achieve.
__________________
John Bright, RV-6A 25088, at FWF
O-360, 8.5:1, vert sump, SDSEFI EM-5
Z-14 adapted for EFI, wiring and IP CAD files here
Newport News, Va
Reply With Quote
  #90  
Old 05-16-2018, 07:22 PM
DanH's Avatar
DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
Posts: 7,539
Default

Quote:
Originally Posted by johnbright View Post
Sorry to state the obvious but one "Oh ****" switch that's always there is the injector ECU select switch if you have dual ECUs.
True enough. For now we can only hope some EFI vendor will eventually automate the injector ECU swap.

On topic, we don't want to add more OSS's in the supporting electrical system.
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 04:21 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.