OK Ed Anderson.

I bought two of these four channel thermal couple RS232 network

modules

and 50 feet of K type thermal couple wire from omega.com.
I bought K type as we can use it for turbine inlet temp and
other exhaust system temperature measurements. Over kill
of course on rad air outlet. I can make up junctions with
my tig welder.

Do you have a notebook computer?
If so let me know when you are ready to make some measurements
for us and I can ship you the system on loan.

If not I can fly over there and bring my notebook computer
and help out.

BTW Vince Leonardo the engineer at Omega (ext 2319) understood

immediately

what we were up to putting rotary engines in airplanes as he was
very very familiar with piston engine exhaust valve problems. In his

opinion

exhaust valve failure in heavy duty piston engines is not a question
of if.... but is a question of.... how soon :-)

Paul Lamar

OK Paul Lamar,

    Yes, I have a portable, a Toshiba 100 Mhz unit I used to program the
HALTECH Fuel Injection system I first had on my engine.  I checked and

it

does have a RS-232 port (capable of 9600 baud I believe) and 770MB of
Harddrive storage, but does not have Visual Basic or other programming
language installed.  I presume its editor can be used to list the

command

codes in ASCII and send them to the COM1 port..

 I've briefly scanned the documentation on the D5000 and it looks like a
very simple set of read/write/configure commands to be set up on the
portable to read/write to the COM1 port.  Since you said you had the K

temp

junctions, I presume you have the D5321 RS-232  model of the data

collector.

Two of these 4 channel data collectors would of course provide 8

potential

locations for the K thermocouples.  It appears from the literature that

two

or more modules can be daisy-chained to allow many modules to work off

one

RS-232 port with an unique identification code for each module and its

data

read back.

So it looks like 1. Decide on what you want to measure/where 2.  install

the

K thermocouples at selected locations,3. write the code to query each

module

and store its data on the harddisk and 4. go fly and collect data. I

guess a

cable needs to be constructed to provide power to the modules and for

data

interface.

If you could zip and send me a copy of the diskette with the sample

code, I

could start playing with it and see what I can come up with as far as

code

(or alternatively, you can write and check out the code and ship it to

me)..

Then we can decide when to ship the unit to me. Also, some indication

about

where you may want to locate the sensors.  Sounds like an interesting
project.

Ed Anderson

Thanks Ed. Yes on the D5321.
I'll check the software tomorrow when I get it but they probably supply a
compiled version so it should run without having to have VB or do
any program modifications. I will also supply all cables and
make up the thermal couples. Figure on mounting the module on a cool
place under the cowl and let me know how long you want the
thermocouple wires.  You will also have to connect it to a source
of 12V.

All we need right at the moment is OAT and one measurement behind
one evap core under worse case cooling conditions. Say climb out.
OAT hot or cold does not matter as all we are looking for is the air temp
increase through the evap core. Any other measurements you feel like
making are icing on the cake.

I was thinking about measuring the temp on
the outside of the exhaust pipes every four inches to get a feel
for how fast the temp falls off on the pipes downstream from the
engine. Would help when designing mufflers.

I will drill two small holes in my rotor housings next to the spark
plugs and measure cyl head (so to speak) temperature near the
combustion chamber.

BTW I have a third module I bought years ago that measures voltages.


Paul Lamar

Unless this module has some sort of compensation, mounting it under the cowl
will throw off the measurements.  Thermocouple read the difference between
the junction and cold end.  The standard calibration is usually 75deg. F.
If ambient is higher or lower, the difference must be added or subtracted.

Tracy

Take another look at the pdf file Tracy. 
Obviously it would be near useless if you had to do that.
It is self calibrating with an onboard CPU.

Paul Lamar
 
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