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

sight tube
Goto page Previous 1, 2

Matronics Email Lists Forum Index -> Europa-List

View previous topic :: View next topic

Author Message

h&jeuropa

Joined: 07 Nov 2006
Posts: 653

Posted: Mon Aug 04, 2008 4:32 am Post subject: Re: sight tube

A couple of responses.



In my experiments, I think some fuel leaked out of the ends but some also must have gone through the wall of the tubing.  Then ends were plugged with 1/4" rods and a plastic clamp.  Any scratch on the rod would allow leakage.



I have Tony K's fuel gauge documentation.  I can email it if anyone wants it.  I just used the sensor and an op amp to make a sensor that puts out 0-5 VDC based on pressure.  I also have a schematic of that if anyone wants that.



Jim Butcher

N241BW

rparigor(at)suffolk.lib.n
Guest

Posted: Mon Aug 04, 2008 11:25 am Post subject: sight tube

">> Yes, this magnet/reed switch idea does seem very

 	  Quote: 	
		  > reliable. Too bad its not avail anymore.

 

 Shown on the Europa site as Mod 60."


	


I am installing the float style 8 position reed switch from Europa.



The way it works is there are magnets in the float and they sweep past the

reed switches and close them. Each station will give a a different

resistance.



I think the 8 stations are probably thought out to give accurate readings

on Europa tank?? The reason I say that is the throw needed is different

near the bottom of the tank and the top.



Pretty neat thing about reed switch and a magnet is there is a certain

natural hysteresis, so if float is bobbing around a bit it will not

constant be moving gauge.



I was not thrilled with the supplied by Europa VDO gauge, so measured the

resistance and had UMA build me a 1+1/4" EL back lit gauge.



If anyone is interested I have notated resistance values for each station.



Ron Parigoris

tonyk(at)kaon.co.nz
Guest

Posted: Mon Aug 04, 2008 1:06 pm Post subject: sight tube

 	  Quote: 	
		  > Was thinking of going with the Tony K idea at one point, but do not know

> where to go to get the schematic/build description/programming data. Yes it

> is quite elegant soln. Let me know if you have this info.


	


www.kaon.co.nz/europa/fuelgaugev3.pdf

 

I am happy to supply the hex files for programming into the two PIC processors required at no charge or can provide a pair of pre programmed PIC processors for USD25. All of the other parts can be sourced from RS Components or Farnell.

 

Regards

 

Tony

gregoryf.flyboy(at)comcas
Guest

Posted: Mon Aug 04, 2008 1:44 pm Post subject: sight tube

 	  Quote: 	
		  the reed switch device is available.


	


Ok, two emails show it is out there yet, I misinterpreted 'Europa used to

sell' in a previous email, is all. There are many options to choose from to

get fuel level readings.



 	  Quote: 	
		  Graham was a skilled innovator who worked for Marconi on radar and stuff.

Graham
	




It Reminds me of the days of Marconi, Tesla, Edison, JP Morgan, and all.

Graham Clarke could probably give us some second-hand history lessons about

some of the earliest radar and radio transmission! (and some of the

rivalries back then)

gregoryf.flyboy(at)comcas
Guest

Posted: Mon Aug 04, 2008 2:01 pm Post subject: sight tube

Jim,



Yes, I suppose with such small volumes it wouldn't take much time for the

volatile substance to leak out. 



I AM interested in the doc and the schematic, if you have them handy. I did

try to get the docs from the source once upon a time, but my email must have

got swallowed somehow. Please send them to me. I like your simple solution

very much.



Thanks in advance,

Greg F






 	  Quote: 	
		  Then ends were plugged with 1/4" rods and a plastic clamp.  Any scratch on

the rod would allow leakage.


	


 	  Quote: 	
		  I have Tony K's fuel gauge documentation.  I can email it if anyone wants

it.  I just used the sensor and an op amp to make a sensor that puts out

0->5 VDC based on pressure.  I also have a schematic of that if anyone wants
	


 	  Quote: 	
		  that.


	


 	  Quote: 	
		  Jim Butcher

N241BW

gregoryf.flyboy(at)comcas
Guest

Posted: Mon Aug 04, 2008 2:05 pm Post subject: sight tube

Oops, I just got your response.  J  

   

Thanks Tony, I just saw your documention. I will decide if I need the hex files, and will let you know if I do.  

   

Thanks much for the effort!  

   

Regards,  

Greg  

         

  

From: owner-europa-list-server(at)matronics.com [mailto:owner-europa-list-server(at)matronics.com] On Behalf Of Tony Krzyzewski

 Sent: Monday, August 04, 2008 2:01 PM

 To: europa-list(at)matronics.com

 Subject: RE: sight tube  

  

       

   

  

    

 	  Quote: 	
		  > Was thinking of going with the Tony K idea at one point, but do not know

 >> where to go to get the schematic/build description/programming data. Yes it
	


 >> is quite elegant soln. Let me know if you have this info.  

    

www.kaon.co.nz/europa/fuelgaugev3.pdf  

    

   

    

I am happy to supply the hex files for programming into the two PIC processors required at no charge or can provide a pair of pre programmed PIC processors for USD25. All of the other parts can be sourced from RS Components or Farnell.  

    

   

    

Regards  

    

   

    

Tony  

  

       [quote][b]

paul.the.aviator(at)gmail
Guest

Posted: Mon Aug 04, 2008 2:25 pm Post subject: sight tube

Greg,



I have been using Tony's system for 4 years and I can say that it

works very nicely.  If you want to round up the HEX files from Tony I

can program the PIC's for you.



Paul

gregoryf.flyboy(at)comcas
Guest

Posted: Mon Aug 04, 2008 2:35 pm Post subject: sight tube

Ron,



 	  Quote: 	
		  Pretty neat thing about reed switch and a magnet is there is a certain

natural hysteresis, so if float is bobbing around a bit it will not

constant be moving gauge.


	


This design does seem bulletproof (I guess its piecewise linear!) 



 	  Quote: 	
		  measured theresistance and had UMA build me a 1+1/4" EL back lit gauge.


	


That will be a pretty display, I have always thought EL lighting produces

some of the best looks out there.



Regards,

Greg

gregoryf.flyboy(at)comcas
Guest

Posted: Mon Aug 04, 2008 2:49 pm Post subject: sight tube

Thanks Paul, you are very kind. I do not currently own the proper

programmer.



My current plan is to go with an MGL Avionics Odyssey. I bet I can take the

sensor output and slightly re-scale it to match the Odyssey input needed,

but have not looked at it yet. It sounds like Jim Butcher has done something

similar.  Tony K's system is so well thought out, that it almost hurts me

not to use it, so If I need a remote sensor output somewhere, I will

definitely take you up on your offer. 



Thanks for your help,



Greg



 	  Quote: 	
		  Greg,


	


 	  Quote: 	
		  I have been using Tony's system for 4 years and I can say that it

works very nicely.  If you want to round up the HEX files from Tony I

can program the PIC's for you.


	


 	  Quote: 	
		  Paul

tonyk(at)kaon.co.nz
Guest

Posted: Mon Aug 04, 2008 3:48 pm Post subject: sight tube

 	  Quote: 	
		   My current plan is to go with an MGL Avionics Odyssey. I bet I can take the

 sensor output and slightly re-scale it to match the Odyssey input needed,

 but have not looked at it yet. 

 
	


If you are using a system that a 0-5v input and has it's own scaling capability (such as the Dynon) then all you need is the power supply, pressure transducer, amplifier and clamping diode part of my circuit. I'd just add a 22k ohm resistor in the output line to limit the current.

 

Fill the tank and then adjust the potentiometer on the amplifier to give you 5v at the input of your instrument. Once you have done that you can follow the linearisation process provided by the instrument manufacturer.

 

Tony

gregoryf.flyboy(at)comcas
Guest

Posted: Mon Aug 04, 2008 8:36 pm Post subject: sight tube

Yes, it looks like I would be able to use the same input conditioning for an EFIS that you used for the PIC. I would need both the 12V regulator (sensor and Burr-Brown amp) and 5 volt regulator  to use the clamping diodes.   

   

I looked up info on the Odyssey again, and it will handle up to two tank inputs, but it wants resistive inputs to its engine management system. Remembering back, this is another reason I went with a standard float type sensor.   

   

That said, I think an analog fuel level gauge would look nice (and fit) on the center console, close to the fuel valve. Could simplify, and get rid of the clamp circuit.  Linearity of fuel used might be my only problem then, and that is where reverting back to the PIC circuitry may have to happen.  Chasing my tail in this paragraph. J  

   

If I had stuck with the Dynon EFIS idea, it would have made this part easier.  

                                                                                                                                                                                             

Greg F  

         

  

From: owner-europa-list-server(at)matronics.com [mailto:owner-europa-list-server(at)matronics.com] On Behalf Of Tony Krzyzewski

 Sent: Monday, August 04, 2008 4:44 PM

 To: europa-list(at)matronics.com

 Subject: RE: sight tube  

  

       

 	  Quote: 	
		   My current plan is to go with an MGL Avionics Odyssey. I bet I can take the

 > sensor output and slightly re-scale it to match the Odyssey input needed,
	


 > but have not looked at it yet.   

    

   

    

If you are using a system that a 0-5v input and has it's own scaling capability (such as the Dynon) then all you need is the power supply, pressure transducer, amplifier and clamping diode part of my circuit. I'd just add a 22k ohm resistor in the output line to limit the current.  

    

   

    

Fill the tank and then adjust the potentiometer on the amplifier to give you 5v at the input of your instrument. Once you have done that you can follow the linearisation process provided by the instrument manufacturer.  

    

   

    

Tony  

    

   

    

   

  

    

   

  

       [quote][b]

craigb(at)onthenet.com.au
Guest

Posted: Wed Aug 06, 2008 1:19 am Post subject: sight tube

Greg

  

 I too  am looking at going with the Odyssey, and i asked the australian distributor  about fuel senders. and they indicated that the resistive  sender

 is  preferred, but only because they feel it to be more accuate, I was told it would  work fine with the capacitance type sender but readings will  vary

 depending on fuel type used, which i believe has been covered quite a bit  here already. It is possible though that the distributor has it  wrong.

  

 One  thing i was considering was another circuit between

 the  EFIS and my capacitance sender so i can calibrate the sender to the  fuel type to get a more accurate reading depending on AVGAS / MOGAS / Blend of  the two

 contents in the tank itself.

  

 craig

 [quote]   --

gregoryf.flyboy(at)comcas
Guest

Posted: Thu Aug 07, 2008 6:34 am Post subject: sight tube

Craig,  

   

You might already be aware of this, but in my judgement, the shifting problem is not related to the EFIS, but is an artifact coming from the capacitance sensor, based on fuel type.  

Interesting that they mentioned it would work with the capacitance probes.  

Did they ever tell you that it can handle a 0–5V input (or at least a voltage input range)? It would be nice to know if this is the case, since then the Odyssey could be used to compensate for the fuel usage linearity issue if someone were to go the pressure sensor/amplifier route.  

   

The Odyssey has two fuel inputs. Each one could have a different transfer curve (would need to check, to be absolutely sure). If you are only using one cap probe, you should be able to switch back and forth between the two inputs, depending on which type of fuel you are using. This would handle two of the 3 conditions conditions anyway ( such as a full tank of AVGAS or one of Mogas10%). It would require operator intervention, though, to manually make the switch based on the condition.  

   

Mogas fuel with ethanol should have a higher conductance than without. I assume it is the conductivity change that affects the capacitance probe measurement. If this was the case, then I suppose someone could do some testing on mogas (and avgas, to see if it is the same as non-ethanol mogas), and come up with a graph of conductivity vs. fuel type. Using this info, that other circuit you are talking about might be able to dynamically change its output based on conductance, and feed this to the EFIS, which will further process the tanks non-linearity. It might only take a small proportional shift to do the job, but would depend on the tests.  

   

It is nice to know the Odyssey might handle the voltage input. I hope that is the case. Let me know if they gave you more info on this.  

   

Regards,  

Greg  

         

  

From: owner-europa-list-server(at)matronics.com [mailto:owner-europa-list-server(at)matronics.com] On Behalf Of craig bastin

 Sent: Wednesday, August 06, 2008 2:24 AM

 To: europa-list(at)matronics.com

 Subject: RE: sight tube  

  

     

Greg  

    

   

    

 	  Quote: 	
		   I was told it would work fine with the capacitance type sender but readings will vary  

    
	


 	  Quote: 	
		  depending on fuel type used, which i believe has been covered quite a bit here already. It is possible though that the distributor has it wrong.  

    
	


   

    

One thing i was considering was another circuit between  

    

the EFIS and my capacitance sender so i can calibrate the sender to the fuel type to get a more accurate reading depending on AVGAS / MOGAS / Blend of the two  

    

contents in the tank itself.  

    

   

    

craig  

  [quote]  

--

Display posts from previous:

	Matronics Email Lists Forum Index -> Europa-List	All times are GMT - 8 Hours Goto page Previous 1, 2
Page 2 of 2

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