Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

LSE Tach

Matronics Email Lists Forum Index -> RV10-List

View previous topic :: View next topic

Author Message

sam(at)fr8dog.net
Guest

Posted: Thu Aug 07, 2008 4:02 pm Post subject: LSE Tach

Ok guy's, I'm at the end of my rope here, I need help. I've tried 

everything I can find to make my LSE tach work in conjunction with a 

Bendix mag. The mag signal to my EIS6000 works just fine, but the 

Lightspeed tach just won't work. I know some of you have it working, 

how's it done?

Tim Olson

Joined: 25 Jan 2007
Posts: 2881

Posted: Thu Aug 07, 2008 5:40 pm Post subject: LSE Tach

I just use the LSE only for tach....I skipped hooking the mag

in at all.  You can hear by ear if it drops a lot of RPM,

and you can see it on the multi-bar bar-graphs if the temps

start to drop or rise.  So there's no real worry to just

have one as long as you listen carefully.



Tim Olson - RV-10 N104CD - Flying

do not archive

Sam Marlow wrote:

 	  Quote: 	
		   

 

 Ok guy's, I'm at the end of my rope here, I need help. I've tried 

 everything I can find to make my LSE tach work in conjunction with a 

 Bendix mag. The mag signal to my EIS6000 works just fine, but the 

 Lightspeed tach just won't work. I know some of you have it working, 

 how's it done?

sam(at)fr8dog.net
Guest

Posted: Thu Aug 07, 2008 6:34 pm Post subject: LSE Tach

Yes, but it's giving up a good diagnostic tool, and backup. I sure wish 

there was a way to have two tach sources.

Tim Olson wrote:

 	  Quote: 	

 I just use the LSE only for tach....I skipped hooking the mag

 in at all.  You can hear by ear if it drops a lot of RPM,

 and you can see it on the multi-bar bar-graphs if the temps

 start to drop or rise.  So there's no real worry to just

 have one as long as you listen carefully.

 Tim Olson - RV-10 N104CD - Flying

 do not archive

 Sam Marlow wrote:

> 

>

> Ok guy's, I'm at the end of my rope here, I need help. I've tried 

> everything I can find to make my LSE tach work in conjunction with a 

> Bendix mag. The mag signal to my EIS6000 works just fine, but the 

> Lightspeed tach just won't work. I know some of you have it working, 

> how's it done?

>

Dave(at)AirCraftersLLC.co
Guest

Posted: Thu Aug 07, 2008 8:32 pm Post subject: LSE Tach

Sam,



I'm not sure if this is what you're after, but here is a schematic to get

two tach signals into a single input so you can do a mag check and see the

actual indicated RPM.



If you need to convert the LSE signal to something the EIS can handle, I'm

sure either vendor can help you out there.



Dave Saylor

AirCrafters LLC

140 Aviation Way

Watsonville, CA 

831-722-9141

831-750-0284 CL

www.AirCraftersLLC.com

Mag_Switch_for_electric_tach_REV_1.pdf

Description:

Download

Filename:

Mag_Switch_for_electric_tach_REV_1.pdf

Filesize:

12.8 KB

Downloaded:

380 Time(s)

jim(at)CombsFive.Com
Guest

Posted: Fri Aug 08, 2008 5:31 am Post subject: LSE Tach

What about having a switch on the panel to let you select the source (LSE or MAG)?

I do as Tim does.  LSE is the only input I use for the tach.  

Jim C

N312F - Finishing

Do Not Archive

============================================================

From: Sam Marlow <sam(at)fr8dog.net>

Date: 2008/08/07 Thu PM 10:33:29 EDT

To: rv10-list(at)matronics.com

Subject: Re: LSE Tach

Yes, but it's giving up a good diagnostic tool, and backup. I sure wish 

there was a way to have two tach sources.

Tim Olson wrote:

 	  Quote: 	

 I just use the LSE only for tach....I skipped hooking the mag

 in at all.  You can hear by ear if it drops a lot of RPM,

 and you can see it on the multi-bar bar-graphs if the temps

 start to drop or rise.  So there's no real worry to just

 have one as long as you listen carefully.

 Tim Olson - RV-10 N104CD - Flying

 do not archive

 Sam Marlow wrote:

> 

>

> Ok guy's, I'm at the end of my rope here, I need help. I've tried 

> everything I can find to make my LSE tach work in conjunction with a 

> Bendix mag. The mag signal to my EIS6000 works just fine, but the 

> Lightspeed tach just won't work. I know some of you have it working, 

> how's it done?

>

============================================================

bcondrey

Joined: 03 Apr 2006
Posts: 580

Posted: Fri Aug 08, 2008 5:52 am Post subject: LSE Tach

Sam,



You can install a tach generator (look on Van's website) and use that to

feed the EIS.  This is a device that uses the mechanical tach drive and

produces an output usable by a variety of engine monitors.  It would be

independent of the type of ignition system.



Bob



--

Tim Olson

Joined: 25 Jan 2007
Posts: 2881

Posted: Fri Aug 08, 2008 6:15 am Post subject: LSE Tach

Yes, there are ways around the problem by adding

complexity, but...  The EIS uses a setting of 1.5 Pulses

per revolution (a setting of "0" on the EIS's Tach P/R

field), and the lightspeed provides 3 pulses per rev,

and the EIS Tach P/R gets set to 3.  So from the beginning,

you're set up with 2 varying pulse counts that you need

the system set for.  So you either need to add circuitry

to modify one, or the other, so that they match.  To me,

this is a waste of time and effort for something so

minor.  I can see on the tach that when I run on the LSE

only, I get a mag drop of maybe 10-20 RPM.  And as soon

as I switch to the mag it does drop a larger drop than

with the EIS only.

The thing is, misfiring or non-firing will be seen on

the EGT gauge too, so you DO have a diagnostic too. And,

the running smoothness of the engine is another diagnostic

tool.  With the LSE ignition I haven't EVER had fouled

plugs that caused a rough running mag drop test.  I used

to have fouled plugs every few flights on the Sundowner

I flew.  It's just not the case with the IO-540 and a

LSE ignition.  If I have a large mag drop, I'll know,

because I can hear it.  If the mag is running rough, I'll

know...because I can hear it.  And, if it's truly not

running good because of a fouled plug on the mag side,

then you'll see the EGT drop off if it isn't firing.  I've

watched this on an piper with an avidyne system.  In the

end, the actual RPM dropped is really not much help

in diagnosing anything, compared to the EGT graph, and

your calibrated ears.  Sure, it's a small trade-off, but

it's one that I definitely don't feel like I'm missing

something with.

Tim Olson - RV-10 N104CD - Flying

do not archive

jim(at)CombsFive.Com wrote:

 	  Quote: 	

 What about having a switch on the panel to let you select the source (LSE or MAG)?

 I do as Tim does.  LSE is the only input I use for the tach.  

 Jim C

 N312F - Finishing

 Do Not Archive

 ============================================================

 From: Sam Marlow <sam(at)fr8dog.net>

 Date: 2008/08/07 Thu PM 10:33:29 EDT

 To: rv10-list(at)matronics.com

 Subject: Re: LSE Tach

 Yes, but it's giving up a good diagnostic tool, and backup. I sure wish 

 there was a way to have two tach sources.

 Tim Olson wrote:

> 

>

> I just use the LSE only for tach....I skipped hooking the mag

> in at all.  You can hear by ear if it drops a lot of RPM,

> and you can see it on the multi-bar bar-graphs if the temps

> start to drop or rise.  So there's no real worry to just

> have one as long as you listen carefully.

>

> Tim Olson - RV-10 N104CD - Flying

> do not archive

> Sam Marlow wrote:

>> 

>>

>> Ok guy's, I'm at the end of my rope here, I need help. I've tried 

>> everything I can find to make my LSE tach work in conjunction with a 

>> Bendix mag. The mag signal to my EIS6000 works just fine, but the 

>> Lightspeed tach just won't work. I know some of you have it working, 

>> how's it done?

>>

>

 ============================================================

carl.froehlich(at)cox.net
Guest

Posted: Fri Aug 08, 2008 6:29 am Post subject: LSE Tach

Sam



I worked this problem in my 8A six years ago.  After talking to Klaus at

LightSpeed and not getting anywhere, I called Grand Rapids.  They figured

that the LightSpeed tach pulse was too narrow for the EIS to recognize.

Grand Rapids came up with a modification to the EIS so that it worked with

the LightSpeed signal.  The modification was simple, just changing a

resistor on the EIS board that I did myself.



Give Grand Rapids a call.



The superior customer service from Grand Rapids is the main reason I'll be

using their EFIS in my RV-10.



Carl Froehlich

RV-8A (450 hrs)

RV-10 (fuselage)



--

bcondrey

Joined: 03 Apr 2006
Posts: 580

Posted: Fri Aug 08, 2008 7:05 am Post subject: LSE Tach

Carl,



The issue isn't the EIS/LSE integration (current versions of the Plasma

III just drive the EIS direct with no mods to either).  The issue is as

Tim describes below - the EIS can be configured to expect pulses as

conditioned by either the LSE or mag but not both at the same time.

There are solutions that add complexity - a circuit to change the pulse

counts from one of the devices or a tach generator off the engine's

mechanical tach connection, but in the end it really isn't a big deal to

just drive the tach off of one of the devices.



Besides, if you're unlucky enough to have one of the early MT governors

you get your ears tuned into hearing a 100 RPM engine change  



Bob

N442PM (flying)



--

sam.marlow

Joined: 25 Feb 2006
Posts: 99

Posted: Fri Aug 08, 2008 4:45 pm Post subject: LSE Tach

The problem with the switch is EIS interitation, the Mag requires a different setting than the LSE.

---- jim(at)CombsFive.Com wrote: 

=============

What about having a switch on the panel to let you select the source (LSE or MAG)?

I do as Tim does.  LSE is the only input I use for the tach.  

Jim C

N312F - Finishing

Do Not Archive

============================================================

From: Sam Marlow <sam(at)fr8dog.net>

Date: 2008/08/07 Thu PM 10:33:29 EDT

To: rv10-list(at)matronics.com

Subject: Re: LSE Tach

Yes, but it's giving up a good diagnostic tool, and backup. I sure wish 

there was a way to have two tach sources.

Tim Olson wrote:

 	  Quote: 	

 I just use the LSE only for tach....I skipped hooking the mag

 in at all.  You can hear by ear if it drops a lot of RPM,

 and you can see it on the multi-bar bar-graphs if the temps

 start to drop or rise.  So there's no real worry to just

 have one as long as you listen carefully.

 Tim Olson - RV-10 N104CD - Flying

 do not archive

 Sam Marlow wrote:

> 

>

> Ok guy's, I'm at the end of my rope here, I need help. I've tried 

> everything I can find to make my LSE tach work in conjunction with a 

> Bendix mag. The mag signal to my EIS6000 works just fine, but the 

> Lightspeed tach just won't work. I know some of you have it working, 

> how's it done?

>

============================================================

sam.marlow

Joined: 25 Feb 2006
Posts: 99

Posted: Fri Aug 08, 2008 4:46 pm Post subject: LSE Tach

I'll look into that,thanks for the tip!

---- "Condrey wrote: 



=============




Sam,



You can install a tach generator (look on Van's website) and use that to

feed the EIS.  This is a device that uses the mechanical tach drive and

produces an output usable by a variety of engine monitors.  It would be

independent of the type of ignition system.



Bob



--

sam.marlow

Joined: 25 Feb 2006
Posts: 99

Posted: Fri Aug 08, 2008 4:54 pm Post subject: LSE Tach

I did that already, didn't help.



---- Carl Froehlich <carl.froehlich(at)cox.net> wrote: 



=============




Sam



I worked this problem in my 8A six years ago.  After talking to Klaus at

LightSpeed and not getting anywhere, I called Grand Rapids.  They figured

that the LightSpeed tach pulse was too narrow for the EIS to recognize.

Grand Rapids came up with a modification to the EIS so that it worked with

the LightSpeed signal.  The modification was simple, just changing a

resistor on the EIS board that I did myself.



Give Grand Rapids a call.



The superior customer service from Grand Rapids is the main reason I'll be

using their EFIS in my RV-10.



Carl Froehlich

RV-8A (450 hrs)

RV-10 (fuselage)



--

sam.marlow

Joined: 25 Feb 2006
Posts: 99

Posted: Fri Aug 08, 2008 4:58 pm Post subject: LSE Tach

Yes but without a second source for tach, I've already scrubed a flight, and postponed another for lack of RPM indication,when the "P" lead ground shield worked it's way loose on the mag.



---- "Condrey wrote: 



=============




Carl,



The issue isn't the EIS/LSE integration (current versions of the Plasma

III just drive the EIS direct with no mods to either).  The issue is as

Tim describes below - the EIS can be configured to expect pulses as

conditioned by either the LSE or mag but not both at the same time.

There are solutions that add complexity - a circuit to change the pulse

counts from one of the devices or a tach generator off the engine's

mechanical tach connection, but in the end it really isn't a big deal to

just drive the tach off of one of the devices.



Besides, if you're unlucky enough to have one of the early MT governors

you get your ears tuned into hearing a 100 RPM engine change  



Bob

N442PM (flying)



--

sam.marlow

Joined: 25 Feb 2006
Posts: 99

Posted: Fri Aug 08, 2008 5:04 pm Post subject: LSE Tach

This is pretty much the way I wired it, but it only works on the mag side with this configuration.

LSE is no help,and I did the EIS mod, still dosen't work.



---- Dave Saylor <Dave(at)AirCraftersLLC.com> wrote: 



=============

Sam,



I'm not sure if this is what you're after, but here is a schematic to get

two tach signals into a single input so you can do a mag check and see the

actual indicated RPM.



If you need to convert the LSE signal to something the EIS can handle, I'm

sure either vendor can help you out there.



Dave Saylor

AirCrafters LLC

140 Aviation Way

Watsonville, CA 

831-722-9141

831-750-0284 CL

www.AirCraftersLLC.com

coop85(at)cableone.net
Guest

Posted: Sat Aug 09, 2008 5:32 am Post subject: LSE Tach

I opted for the switch method and it works well, however the LSE sends 2 pulses for every 1 the mag sends.  I set up the EIS to read the LSE info as primary so if I switch to the mag source I have to mentally double the indicated RPM.  In all honesty I usually do Tim's method of audio verification of minimal drop in RPM, but I wanted the option if required.



Marcus



--

Tim Olson

Joined: 25 Jan 2007
Posts: 2881

Posted: Sat Aug 09, 2008 6:13 am Post subject: LSE Tach

Marcus is right.  I considered doing the same thing...just

leaving the 2 tach readings being different, and just

remembering that one would read a proportional number to

the other.  It would be pretty easy to wire.  I just decided

not to bother.....but I think the way he did it would be a

great compromise if someone were interested in both readings,

but didn't want the added cost and LESS reliability of a

mechanical tach sender.



Tim Olson - RV-10 N104CD - Flying

do not archive

Marcus Cooper wrote:

[quote] 

 <coop85(at)cableone.net>

 

 I opted for the switch method and it works well, however the LSE

 sends 2 pulses for every 1 the mag sends.  I set up the EIS to read

 the LSE info as primary so if I switch to the mag source I have to

 mentally double the indicated RPM.  In all honesty I usually do Tim's

 method of audio verification of minimal drop in RPM, but I wanted the

 option if required.

 

 Marcus

 

 --

Display posts from previous:

	Matronics Email Lists Forum Index -> RV10-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