nuckolls.bob(at)cox.net
Guest
|
 Posted: Mon Mar 10, 2008 7:18 am Post subject: Diode from the Main Bus to the Endurance Bus |
 |
|
At 10:59 PM 3/9/2008 -0400, you wrote:
| Quote: |
Hi Folks
I have already one airplane flying using Bob's Z-11 architecture with
absolutely no issues. It has been great & really appreciated all the info
provided by Bob & the forum.
I do have one question. I am not questioning the wisdom of the design but
merely wondering why a diode is placed between the main bus & the
endurance bus. I realize that it is there to prevent backfeeding from the
E bus to the main bus when the master is turned off in the case of an
alternator failure etc.
However, you can easily install a 2-10 switch that could be used to set to
1/ Both buses off
2/ E bus only on, master off & all other buses turned off
3/ Main bus & E bus on with the E bus being fed through the main bus & master
Is the considered opinion of the group that a diode is more reliable than
a switch & therefore used, or, to simplify the whole design or what?
Just curious as there is a slight power loss across the diode of course
which is the only negative and think of at this point.
|
The design goal is to have TWO INDEPENDENT paths of
power to the e-bus, ONE of which is battery direct so
that one can operate e-bus loads with the battery
master switch off.
If you use a single switch in the mode you've described,
there is a single point of failure in the switch.
Voltage drop in the diode is not significant. Consider
the fact that when power is expected to come through the
diode, the alternator is operating. This raises the main
bus to 14.2 to 14.6 volts. A typical 0.7 volt drop in the
diode offers an e-bus supply of 13.5 to 13.9 volts . . .
entirely satisfactory supply levels.
Contrast normal operating conditions with battery-only
operations where the e-bus will start out at 12.5 and
drop to 11.0 by the time the battery is used up.
Bob . . .
| | - 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
