 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
sarg314(at)gmail.com
Guest
|
 Posted: Sat May 30, 2009 7:49 pm Post subject: sky-tec starter wiring |
 |
|
Sky-Tec advises against the use of a starter relay, while Bob K.
advocates the use of one (for good reason, as I recall). I have a
separate starter relay in my plane. A couple years ago the Sky-Tec
website had an example schematic for hooking up one of their starters
with a separate starter relay. I had a copy of that, but now I can't
find it and they seem to have removed it from their website.
I believe it showed a jumper between the large +12v terminal and the
small terminal on the starter. Does any one have a copy of that
schematic?
Thanks,
--
Tom Sargent, RV-6A, final assembly.
| | - 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 |
|
|
|
| Back to top |
|
 |
wgill10(at)comcast.net
Guest
|
|
| Back to top |
|
|
sarg314(at)gmail.com
Guest
|
| Posted: Sun May 31, 2009 9:26 am Post subject: sky-tec starter wiring |
|
|
William:
I followed the link back to sky-tec (yet again) and this time I found
what I was looking for. Thanks for making me look again. Seems my
current wiring set-up matches their "certified" diagram, tht is, the
diagram for planes with a starter contactor.
On May 31, 2009, at 9:40 AM, William Gill wrote:
| | - 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 |
|
|
|
| Back to top |
|
|
nuckolls.bob(at)aeroelect
Guest
|
| Posted: Sun May 31, 2009 6:47 pm Post subject: sky-tec starter wiring |
|
|
At 10:46 PM 5/30/2009, you wrote:
| Quote: |
Sky-Tec advises against the use of a starter relay, while Bob K.
advocates the use of one (for good reason, as I recall). I have a
separate starter relay in my plane. A couple years ago the Sky-Tec
website had an example schematic for hooking up one of their starters
with a separate starter relay. I had a copy of that, but now I can't
find it and they seem to have removed it from their website.
I believe it showed a jumper between the large +12v terminal and the
small terminal on the starter. Does any one have a copy of that
schematic?
|
Not so long ago in a galaxy very close by,
the first made-for-aircraft light weight starters
were offered by B&C in Newton, KS. The crafters
of design goals and system integrators of those
products were cognizant of the extra-ordinary
performance of the electrical control contactor/
pinion engagement solenoid . . . but at a price.
See:
http://www.aeroelectric.com/articles/strtctr.pdf
The inductive, high engagement current of
these devices was higher than any contemporary
starter control switches were designed to handle.
Indeed, a number of automobile starter switch
contacts were ill-designed to stroke these
little beasts.
Further, part of the anticipated market for these
starters included type certificated machines that
were already fitted with intermittent duty,
starter contactors.
The marketing philosophy adopted for the B&C
starters was to tie the solenoid coil terminal
to the starter contactor's fat terminal as
depicted in Figure 6 of the paper cited above.
This philosophy mitigated the need for extra-
husky starter switches -AND- offer a drop-in
replacement for TC aircraft starters without
modification of ship's wiring.
Then came competing designs with permanent
magnet motors. Attempts to wire these starters
in the same manner produced a delayed retraction
of the starter pinion gear after the start
button was released. This was a byproduct
of voltage GENERATED by the PM motors as they
spun down. This "counter emf" held the pinion
gear engaged for several seconds.
The PM motor product designer's recommendation
was to wire it just like in cars . . . but they
either overlooked or ignored the inrush current
demands described in the article cited above.
The AEC work-around was to add a starter
control "boost relay" as depicted in Figure Z-22
which isolates the panel mounted start switch
from the extra-ordinary demands of the starter
solenoid/contactor combination.
See also Figures Z-22 notes on page Z-5
of
http://aeroelectric.com/R12A/AppZ_12A3.pdf
So. Your options are (1) wire per the manufacturer's
instructions and select a starter control push-button
or switch suited to the task (don't forget the arc-suppression
diode) or (2) wire per Z-22.
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 |
|
|
|
| Back to top |
|
|
tshankland(at)sbcglobal.n
Guest
|
| Posted: Mon Jun 01, 2009 4:42 am Post subject: sky-tec starter wiring |
|
|
I have been following this thread with some interest as in been there
done that. My Stratus Suburu setup required an automotive type switch,
ignition, close for run. After a search for a compact simple switch I
turned to one of my trusted sources, John Deere. Yes they had a compact
ignition switch with starter function for a good price. Flash ahead a
year or so, during my 40 hour test phase I was getting intermittent
failures to engage especially when the engine was hot, you know you fly
to the airport and then go to leave and it does want to start. Well I
tracked it down to an excessive voltage drop across the switch. So off
to the John Deere dealer for a new one. Talking to the dealer about my
problem I found that they had the same problem on many of their tractors
and John Deere had a fix. A nice tab mount relay suitable to mount on
the starter that reduced the current load such that even the old switch
works. I was able to make the entire change under the cowling by the
starter and didn't have to get in to the instrument panel at all. John
Deere come through again, after all that is where I get my oil filters.
Tim Shankland
thomas sargent wrote:
| Quote: |
<sarg314(at)gmail.com>
William:
I followed the link back to sky-tec (yet again) and this time I
found what I was looking for. Thanks for making me look again.
Seems my current wiring set-up matches their "certified" diagram, tht
is, the diagram for planes with a starter contactor.
On May 31, 2009, at 9:40 AM, William Gill wrote:
>
> <wgill10(at)comcast.net >
>
> Try: http://www.skytecair.com/Wiring_Diag.htm
>
|
| | - 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 |
|
|
|
| Back to top |
|
|
nuckolls.bob(at)aeroelect
Guest
|
| Posted: Mon Jun 01, 2009 5:32 am Post subject: sky-tec starter wiring |
|
|
At 07:40 AM 6/1/2009, you wrote:
<tshankland(at)sbcglobal.net>
I have been following this thread with some interest as in been there
done that. My Stratus Suburu setup required an automotive type
switch, ignition, close for run. After a search for a compact simple
switch I turned to one of my trusted sources, John Deere. Yes they
had a compact ignition switch with starter function for a good price.
Flash ahead a year or so, during my 40 hour test phase I was getting
intermittent failures to engage especially when the engine was hot,
you know you fly to the airport and then go to leave and it does want
to start. Well I tracked it down to an excessive voltage drop across
the switch. So off to the John Deere dealer for a new one. Talking to
the dealer about my problem I found that they had the same problem on
many of their tractors and John Deere had a fix. A nice tab mount
relay suitable to mount on the starter that reduced the current load
such that even the old switch works.
<snip>
My first encounter with the extra-ordinary demands
of the modern two-step starter engagement solenoids
was on one of my employees cars at Vidimation about
17 years ago. It was a Japanese car as I recall . . .
it was experiencing intermittent responses to twisting
the key switch to the START position.
He pulled the switch in our shop and we discovered
bare brass, sliding (read low pressure, slow moving)
contacts for the start function were all burned up.
The car had about 60K miles on it.
A new switch fixed the problem . . . no doubt for
perhaps another 60K miles? I'd didn't take
time to dissect the physics behind the phenomenon
then. But it looks like the "boost" relay fix
has occurred to more than one individual seeking
an alternative recipe for success.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
| | - 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 |
|
|
|
| Back to top |
|
|
frank.hinde(at)hp.com
Guest
|
| Posted: Mon Jun 01, 2009 7:05 am Post subject: sky-tec starter wiring |
|
|
This brings up an issue that has been beaten around a lot...Especially by myself in the past.
On your Stratus you should have two ignition systems and I dearly hope you are not running the feed for both ignitions through that single key switch because the key switch is a single point of faiure.
The two ignitions should be treated as totally separate entities, that means a separate fused circuit, separate swicthing and wiring..I.e no single component failing should stop the engine running.
I know Cessna's use a separate two postion switch but the get away this because the switch is a fail safe device..i.e if continuity stops the engine continues to run...But even then I avoided this route on my current airplane.
Cheers
Frank
Stratus 601 zenair
RV7a
--
| | - 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 |
|
|
|
| Back to top |
|
|
tshankland(at)sbcglobal.n
Guest
|
| Posted: Mon Jun 01, 2009 8:38 am Post subject: sky-tec starter wiring |
|
|
Frank,
My electrical system consists of two batteries and two independent
buses, A & B. All power connections are through center off single pole
double throw switches. Thus I can run any part of my system on either
bus of my choosing or all on one bus. The primary ignition circuit,
which feeds the ignition switch goes through one of these switches,
normally set to bus A. The secondary ignition, fuel pump and starter are
all fed by single rocker switches. By the way I have a guard over the
primary ignition rocker switch so as not to inadvertently turn if off
during some switching. This allows me to start my plane like a car, turn
on Bus A turn the key and your running. It also allows me to separate
noisy devices like strobes on one bus and the radio on the other. I also
have a relay that connects both batteries for starting.
Tim Shankland
Hinde, Frank George (Corvallis) wrote:
[quote]
This brings up an issue that has been beaten around a lot...Especially by myself in the past.
On your Stratus you should have two ignition systems and I dearly hope you are not running the feed for both ignitions through that single key switch because the key switch is a single point of faiure.
The two ignitions should be treated as totally separate entities, that means a separate fused circuit, separate swicthing and wiring..I.e no single component failing should stop the engine running.
I know Cessna's use a separate two postion switch but the get away this because the switch is a fail safe device..i.e if continuity stops the engine continues to run...But even then I avoided this route on my current airplane.
Cheers
Frank
Stratus 601 zenair
RV7a
--
| | - 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 |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
