Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

electrical system master contactor

 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> AeroElectric-List
View previous topic :: View next topic  
Author Message
Bill Allen



Joined: 24 Aug 2009
Posts: 42
Location: UK

PostPosted: Wed Aug 19, 2015 7:29 am    Post subject: electrical system master contactor Reply with quote

Hi,

The master contactor pulls about 1.5 amps which is more than many components  that "work for their living" 
Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;
http://tinyurl.com/nupw5xu
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

On 19 August 2015 at 15:00, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
Quote:
At 11:21 PM 8/18/2015, you wrote:

Quote:
The battery contactor pulls nearly a full amp. Also it is very easy to shed unneeded load by shutting  the main down and going with the "E" bus.

  Z-12 doesn't give you the option of running
  with the battery contactor open . . . Z13-8
  DID offer that mode . . . due to the limited
  output from the SD-8. Of course, it also offers
  a calculated plan-c for operating battery
  only.

  I once offered a Z-13/20 utilizing the
  SD-20 . . . kinda messy and I pulled it.
  I might do some asphalt-cogitation on another
  pass at it. In the mean time, Z-12 is
  exemplary of architectures flying on hundreds
  of TC aircraft of the production lines of
  Beech, Mooney, Piper et. als. . . . except
  their 'e-bus' is an (ugh!!) 'avionics-bus'.



  Bob . . .
Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution





--
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

[quote][b]


- 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
View user's profile Send private message
jmjones2000(at)mindspring
Guest





PostPosted: Wed Aug 19, 2015 8:27 am    Post subject: electrical system master contactor Reply with quote

Electrically there is no reason a manual contactor would not work. The master contractor will go dead and shut the battery off from the rest of the system if the control voltage is cut off (such as a crash). The mechanical switch may not.
Access is the other consideration. If the battery is on the forward side of the firewall you have 2 options. Put it close to the pilot or close to the battery. Neither choice is good. If you put it near the pilot, you have a good amount of rather large gauge wire left unprotected. If you put it near the battery, you may not have immediate access to it if you need it. You may be able to connect a lever or cable to the switch that can bring control into the cockpit but that adds weight, complexity, and another component susceptible to failure.
The solution I came up with is the solid state master relay from Waytek Wire.
http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/
It draws .125ma of current and is good for 300A continuous. Also rated at 500A for 1 second.
It is comparable in weight to a legacy master contactor, and it's heat sink is made from aluminum.
The battery charges perfectly through the relay and I have encountered zero issues with it. It's about twice the cost of a quality legacy contactor, with a rating of millions of cycles. Cutting edge technology.

Justin

On Aug 19, 2015, at 11:28, Bill Allen <billallensworld(at)gmail.com (billallensworld(at)gmail.com)> wrote:
[quote]Hi,

The master contactor pulls about 1.5 amps which is more than many components that "work for their living"
Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;
http://tinyurl.com/nupw5xu
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

On 19 August 2015 at 15:00, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
Quote:
At 11:21 PM 8/18/2015, you wrote:

Quote:
The battery contactor pulls nearly a full amp. Also it is very easy to shed unneeded load by shutting the main down and going with the "E" bus.

Z-12 doesn't give you the option of running
with the battery contactor open . . . Z13-8
DID offer that mode . . . due to the limited
output from the SD-8. Of course, it also offers
a calculated plan-c for operating battery
only.

I once offered a Z-13/20 utilizing the
SD-20 . . . kinda messy and I pulled it.
I might do some asphalt-cogitation on another
pass at it. In the mean time, Z-12 is
exemplary of architectures flying on hundreds
of TC aircraft of the production lines of
Beech, Mooney, Piper et. als. . . . except
their 'e-bus' is an (ugh!!) 'avionics-bus'.



Bob . . .
Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution





--
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

Quote:


D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
lectric-List"">http://www.matronics.com/Navigator?AeroElectric-List
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
//forums.matronics.com
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
ot;">http://www.matronics.com/contribution
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D


[b]


- 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
Bill Allen



Joined: 24 Aug 2009
Posts: 42
Location: UK

PostPosted: Wed Aug 19, 2015 10:20 am    Post subject: electrical system master contactor Reply with quote

Good points well made.

On 19 August 2015 at 17:26, Justin Jones <jmjones2000(at)mindspring.com (jmjones2000(at)mindspring.com)> wrote:
Quote:

Electrically there is no reason a manual contactor would not work.  The master contractor will go dead and shut the battery off from the rest of the system if the control voltage is cut off (such as a crash). The mechanical switch may not. 
Access is the other consideration. If the battery is on the forward side of the firewall you have 2 options. Put it close to the pilot or close to the battery. Neither choice is good. If you put it near the pilot, you have a good amount of rather large gauge wire left unprotected. If you put it near the battery, you may not have immediate access to it if you need it. You may be able to connect a lever or cable to the switch that can bring control into the cockpit but that adds weight, complexity, and another component susceptible to failure. 
The solution I came up with is the solid state master relay from Waytek Wire. 
http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/ 
It draws .125ma of current and is good for 300A continuous. Also rated at 500A for 1 second. 
It is comparable in weight to a legacy master contactor, and it's heat sink is made from aluminum. 
The battery charges perfectly through the relay and I have encountered zero issues with it. It's about twice the cost of a quality legacy contactor, with a rating of millions of cycles. Cutting edge technology. 

 Justin

On Aug 19, 2015, at 11:28, Bill Allen <billallensworld(at)gmail.com (billallensworld(at)gmail.com)> wrote:


Quote:
Hi,

The master contactor pulls about 1.5 amps which is more than many components  that "work for their living" 
Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;
http://tinyurl.com/nupw5xu


Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

On 19 August 2015 at 15:00, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
Quote:
At 11:21 PM 8/18/2015, you wrote:

Quote:
The battery contactor pulls nearly a full amp. Also it is very easy to shed unneeded load by shutting  the main down and going with the "E" bus.

  Z-12 doesn't give you the option of running
  with the battery contactor open . . . Z13-8
  DID offer that mode . . . due to the limited
  output from the SD-8. Of course, it also offers
  a calculated plan-c for operating battery
  only.

  I once offered a Z-13/20 utilizing the
  SD-20 . . . kinda messy and I pulled it.
  I might do some asphalt-cogitation on another
  pass at it. In the mean time, Z-12 is
  exemplary of architectures flying on hundreds
  of TC aircraft of the production lines of
  Beech, Mooney, Piper et. als. . . . except
  their 'e-bus' is an (ugh!!) 'avionics-bus'.



  Bob . . .

Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution





--
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

Quote:


D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
lectric-List"">http://www.matronics.com/Navigator?AeroElectric-List
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
//forums.matronics.com
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
ot;">http://www.matronics.com/contribution
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D



Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution




--
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

[quote][b]


- 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
View user's profile Send private message
nuckolls.bob(at)aeroelect
Guest





PostPosted: Wed Aug 19, 2015 3:07 pm    Post subject: electrical system master contactor Reply with quote

Quote:
The solution I came up with is the solid state master relay from Waytek Wire.

http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/

It draws .125ma of current and is good for 300A continuous. Also rated at 500A for 1 second.

It is comparable in weight to a legacy master contactor, and it's heat sink is made from aluminum.

The battery charges perfectly through the relay and I have encountered zero issues with it. It's about twice the cost of a quality legacy contactor, with a rating of millions of cycles. Cutting edge technology.


Very few OBAM aircraft are fitted with
a 'quality legacy contactor' purchased
at a cost of $90. Similarly, while the
C-140 was first fitted with the 6041H
series 'quality contactor' it was eventually
'down-sized' to the beer-barrel contactors
that were standard in tens of thousands
of airplanes after that . . . and that was
just at Cessna. Production Cessnas use
the beer-barrel contactors to this very day.

In my former life, there were opportunities
to put in an official change proposal. Were I
proposing to replace a beer-barrel contactor
on a current production TC or STC aircraft with
any form of 'upgrade' . . . I would be expected
to present compelling case. An argument to convince
the holders of purse-strings that the change would
(1) reduce demonstrable risk or (2) reduce cost-
of-ownership with the subject airframe.

Most OBAM aircraft builders do not have access
to "the numbers" that put orders of magnitude
on either risk or cost-of-ownership for
comparative analysis. At the same
time, they are personally bombarded with
ads, legends, anecdotes and interesting comparisons
of why you want to fly product A as opposed to product
B. Indeed, many suppliers leaning over the counters
at OSH and buying big ads in S.A. or Kitplanes are
engaged in an activity to 'trade' their particular
offering for an acceptable quantity of your cash.

In every free-market exchange, BOTH parties walk
away thinking they got the 'better deal'. BOTH
gave something they valued less for something they
valued more. In the case before us, we want to
consider the operational or risk value for replacing
a $20 contactor with a $180 contactor. Should you
walk away from a booth at OSH with a $180 contactor,
what arguments might convince you that there was
a positive return on investment for having made
the purchase?

Exactly what are the cost-of-ownership expectations
for the swap? Is there a demonstrated lowering of
risk? Is there not a lot of history for this style
of part used as battery contactors on TC aircraft for
60+ years. Are there documented cases for failures of
such devices placing an airplane/pilot in totally
unmanageable. high risk situations?

We are programmed as mere mortals to worry . . . sometimes
about the wrong things and with risk of making decisions
that don't do much for REAL risk. That's why we preach
the doctrine of FMEA here on the List . . . it's
exceedingly difficult and/or expensive to PURCHASE system
reliability as opposed to BUILDING system reliability
based on demonstrable risk and cost-of-ownership.

I just received an email from EarthX citing their
compliance with the wishes/requirements in battery
performance from an ENGINE manufacturer. No doubt,
recommendations from Rotax will offer powerful
inducements for Rotax owners to be compliant with
the manufacturer's wishes.

They're also looking at upgrades for 'dual battery management
systems' and 'serial data communications with an
EFIS system'. This ol' TC born and bred graybeard would
REALLY like to see the economics/risks arguments
for those change proposals!

The questions to be asked and answered go to
real cost of ownership combined with effects on
risk for incorporating hardware for which you
have little understanding. no chance of repairing
yourself and a expanded sense of helplessness
when the little red light comes on.

I have a car that throws fault codes which,
more often than not, stay cleared after a reset.
On two occasions, the codes were good and I
fixed some things. But now I carry an OBDII code
reader around in the car just to make sure that
any given light is worthy of attention . . .
I think maybe it's better than my 6-cyl, stick
shift Chevys . . . the jury is still out.


Bob . . . [quote][b]


- 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





PostPosted: Wed Aug 19, 2015 7:02 pm    Post subject: electrical system master contactor Reply with quote

At 10:28 AM 8/19/2015, you wrote:
Quote:
Hi,

The master contactor pulls about 1.5 amps which is more than many components  that "work for their living"Â

Actually, the legacy beer-barrel contactors are
not that power hungry.

http://tinyurl.com/mpcgp3t

http://tinyurl.com/k6bwdqo


Quote:
Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;

. . . but if you can place such a switch where it
is easily reached with SHORT connections
to the battery, that's good too. Took dual
instruction in a Tri-Pacer about 1961 that
with manual switches for both the starter
and battery. But battery was under the seat
and wire runs short.




Bob . . . [quote][b]


- 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
bob.verwey(at)gmail.com
Guest





PostPosted: Wed Aug 19, 2015 9:37 pm    Post subject: electrical system master contactor Reply with quote

Thats the route i have gone

On Wednesday, August 19, 2015, Bill Allen <billallensworld(at)gmail.com (billallensworld(at)gmail.com)> wrote:
Quote:
Hi,

The master contactor pulls about 1.5 amps which is more than many components  that "work for their living" 
Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;
http://tinyurl.com/nupw5xu
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

On 19 August 2015 at 15:00, Robert L. Nuckolls, III <[url=javascript:_e(%7B%7D,'cvml','nuckolls.bob(at)aeroelectric.com');]nuckolls.bob(at)aeroelectric.com[/url]> wrote:
Quote:
At 11:21 PM 8/18/2015, you wrote:

Quote:
The battery contactor pulls nearly a full amp. Also it is very easy to shed unneeded load by shutting  the main down and going with the "E" bus.

  Z-12 doesn't give you the option of running
  with the battery contactor open . . . Z13-8
  DID offer that mode . . . due to the limited
  output from the SD-8. Of course, it also offers
  a calculated plan-c for operating battery
  only.

  I once offered a Z-13/20 utilizing the
  SD-20 . . . kinda messy and I pulled it.
  I might do some asphalt-cogitation on another
  pass at it. In the mean time, Z-12 is
  exemplary of architectures flying on hundreds
  of TC aircraft of the production lines of
  Beech, Mooney, Piper et. als. . . . except
  their 'e-bus' is an (ugh!!) 'avionics-bus'.



  Bob . . .
Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution





--
Bill AllenLongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution



--
Best...Bob Verwey

[quote][b]


- 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
billp(at)wwpc.com
Guest





PostPosted: Thu Aug 20, 2015 6:55 am    Post subject: electrical system master contactor Reply with quote

It depends on where your battery is. The Master Contractor should be really close to the battery. The wire between the battery and the Master has no protection and if that wire gets shorted there is nothing you can do about it in flight. It will draw as much current as the battery can supply and turn that into heat, read fire.

If you have your battery on the other side of the firewall and you use something like a marine battery disconnect switch in the engine compartment next to the battery you could extend the switch shaft into the cockpit and put the knob where you can reach it. Another option would be to rig a lever on a marine cutoff switch and use a cable pull control in the cockpit to control the switch.

Remember that the Master <whatever you use> has to be capable of passing engine starting current through it. That's probably the heaviest load you have in the aircraft. Whatever you use has to be rated to at least the current of the starter (when stalled) and anything else that is on during startup. The switch you choose should also be designed to cut off high currents under load. If you have a master bus short you want to be able cut off the battery circuit without the switch exploding from the plasma generated when it opens. That's why I suggested a marine battery cutoff switch. It's a manual switch designed for the purpose.

Bill

On 8/19/15 22:35, Bob Verwey wrote:

[quote]Thats the route i have gone

On Wednesday, August 19, 2015, Bill Allen <[url=mailto:billallensworld(at)gmail.com]billallensworld(at)gmail.com (billallensworld(at)gmail.com)[/url]> wrote:
Quote:
Hi,

The master contactor pulls about 1.5 amps which is more than many components  that "work for their living" 


Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;


http://tinyurl.com/nupw5xu


Bill Allen LongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

On 19 August 2015 at 15:00, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
Quote:
At 11:21 PM 8/18/2015, you wrote:

Quote:
The battery contactor pulls nearly a full amp. Also it is very easy to shed unneeded load by shutting  the main down and going with the "E" bus.

  Z-12 doesn't give you the option of running
  with the battery contactor open . . . Z13-8
  DID offer that mode . . . due to the limited
  output from the SD-8. Of course, it also offers
  a calculated plan-c for operating battery
  only.

  I once offered a Z-13/20 utilizing the
  SD-20 . . . kinda messy and I pulled it.
  I might do some asphalt-cogitation on another
  pass at it. In the mean time, Z-12 is
  exemplary of architectures flying on hundreds
  of TC aircraft of the production lines of
  Beech, Mooney, Piper et. als. . . . except
  their 'e-bus' is an (ugh!!) 'avionics-bus'.



  Bob . . .
Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution






--
Bill Allen LongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ





Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution



--
Best... Bob Verwey







Quote:

[b]


- 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
bob.verwey(at)gmail.com
Guest





PostPosted: Thu Aug 20, 2015 9:07 am    Post subject: electrical system master contactor Reply with quote

Hey Bill, I have the marine type and its about 1ft from the battery which sits under the pilot seat.

On Thursday, August 20, 2015, Bill Putney <billp(at)wwpc.com (billp(at)wwpc.com)> wrote:
Quote:
It depends on where your battery is. The Master Contractor should be really close to the battery. The wire between the battery and the Master has no protection and if that wire gets shorted there is nothing you can do about it in flight. It will draw as much current as the battery can supply and turn that into heat, read fire.

If you have your battery on the other side of the firewall and you use something like a marine battery disconnect switch in the engine compartment next to the battery you could extend the switch shaft into the cockpit and put the knob where you can reach it. Another option would be to rig a lever on a marine cutoff switch and use a cable pull control in the cockpit to control the switch.

Remember that the Master <whatever you use> has to be capable of passing engine starting current through it. That's probably the heaviest load you have in the aircraft. Whatever you use has to be rated to at least the current of the starter (when stalled) and anything else that is on during startup. The switch you choose should also be designed to cut off high currents under load. If you have a master bus short you want to be able cut off the battery circuit without the switch exploding from the plasma generated when it opens. That's why I suggested a marine battery cutoff switch. It's a manual switch designed for the purpose.

Bill

On 8/19/15 22:35, Bob Verwey wrote:

Quote:
Thats the route i have gone

On Wednesday, August 19, 2015, Bill Allen <[url=javascript:_e(%7B%7D,'cvml','billallensworld(at)gmail.com');][/url][url=javascript:_e(%7B%7D,'cvml','billallensworld(at)gmail.com');]billallensworld(at)gmail.com[/url]> wrote:
Quote:
Hi,

The master contactor pulls about 1.5 amps which is more than many components  that "work for their living" 


Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this;


http://tinyurl.com/nupw5xu


Bill Allen LongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ

On 19 August 2015 at 15:00, Robert L. Nuckolls, III <[url=javascript:_e(%7B%7D,'cvml','nuckolls.bob(at)aeroelectric.com');]nuckolls.bob(at)aeroelectric.com[/url]> wrote:
Quote:
At 11:21 PM 8/18/2015, you wrote:

Quote:
The battery contactor pulls nearly a full amp. Also it is very easy to shed unneeded load by shutting  the main down and going with the "E" bus.

  Z-12 doesn't give you the option of running
  with the battery contactor open . . . Z13-8
  DID offer that mode . . . due to the limited
  output from the SD-8. Of course, it also offers
  a calculated plan-c for operating battery
  only.

  I once offered a Z-13/20 utilizing the
  SD-20 . . . kinda messy and I pulled it.
  I might do some asphalt-cogitation on another
  pass at it. In the mean time, Z-12 is
  exemplary of architectures flying on hundreds
  of TC aircraft of the production lines of
  Beech, Mooney, Piper et. als. . . . except
  their 'e-bus' is an (ugh!!) 'avionics-bus'.



  Bob . . .
Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution






--
Bill Allen LongEz160 N99BA FD51
CZ4 G-BYLZ EGBJ





Quote:


ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution



--
Best... Bob Verwey







Quote:



ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution




--
Best...Bob Verwey

[quote][b]


- 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
Display posts from previous:   
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> AeroElectric-List All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
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