leo(at)icn.usyd.edu.au
Guest
|
 Posted: Sun Mar 02, 2008 10:50 pm Post subject: Ignition control in a dual alternator dual bus system |
 |
|
Robert L. Nuckolls, III wrote:
| Quote: |
<nuckolls.bob(at)cox.net>
At 01:30 PM 3/3/2008 +1100, you wrote:
>
> <leo(at)icn.usyd.edu.au>
>
> Dear List,
>
> I am currently designing the electrical system for my "all-electric"
> RV 10. I have been very happy with Bob's architecture for my RV6A
> which worked beautifully the day my alternator died in the clouds.
>
> I am looking at the Z-14 schematic which involves two batteries, two
> alternators and a cross feed for starting and for electron sharing in
> failure mode.
>
> I note that there are no switching diagrams for mags or other
> ignition systems on this diagram. I wondered what the implications
> for mag switching were in this setup. Should they just have simple
> switches but only turn on the impulse coupled mag for a start? If so,
> how serious are the implications if the non-coupled mag is
> accidentally enabled at startup? If I ran an electronic system on the
> left would you only turn this on after start and again stick with
> impulse coupling on the standard mag for the start.
>
> I would be pleased to hear from anyone who has used this schematic as
> the basis for their electrical system as to how they had handled the
> ignition switching.
>
> Thanks for your help.
Leo, Why such a heavy, complex, expensive electrical system?
How about going with Z-13/8 and use the money you saved to
put at least one E-Mag on? Leave your impulse coupled mag in
place and replace the non-coupled with an E or better yet,
a P-Mag. Then, both ignitions can be ON for cranking. If
you ever have the coupled-mag crap, you can put the non-
coupled back on and wire it like Z-27. Make both ignition
switches a DPDT ON-ON (S702-3 or equal) from the get-go.
This will produce an exceedingly reliable system with
a minimum of cost and get you a really nice sparking
ignition for cranking.
Bob . . .
Bob,
|
Thank you for your prompt reply.
The thing that had primarily motivated me towards the Z-14 was the fact
that I am planning to install a Garmin G900X. The specs for this
nominate a current draw of 16-28 amps!
With this mighty beast sucking electrons I was moved towards the B&C 20
amp alternator as a backup and the added reserve of two PC680 batteries
to provide some buffer, as well as additional cranking power for that
big 6 cylinder engine.
I have, as stated above, been very happy with the performance of your
architecture in my current plane so am not inclined to ignore your
suggestions. Having said that, the B&C alternator and regulator have
performed so nicely I was quite looking forward to having two of
them.... 
Do you think the Z 13/8 would carry the Garmin? I sure hate to turn off
all that good stuff just cause an alternator has gone belly up.
Thanks again,
Leo
| Quote: |
!DSPAM:47cb911624381654078673!
|
--
A/Prof Leo Davies,
Sub-Dean, Head of Assessment,
Faculty of Medicine,
Edward Ford Building,
University of Sydney 2006
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
