OAT

[millerwse]

I've installed the OAT sensor on a Dynon D100 per installation instructions
Initial reading is about 13 degree centigrade. Air temperature is 27 degree c.
The adjust limits are plus or minus 10 degrees C so ambient cannot be set The screen will show "not installed" when disconnected.
Setting the indication at maximum seems to get no indication change with temperature however a decrease in temperature will show when "zeroed" and the temper changed.

 

[dynonsupport]

Sorry that your previous post seems to have been messed up by the forum system. Here's what we posted back then, and let's work from here:


The transponder is not related to the OAT.

First, what model is your transponder? The GTX-327 and GTX-330 use serial, the 320 uses parallel.

On the 327/330, have you set up your transponder to be using the serial port for altitude, and set it to Icarus format? Have you set the EFIS to format 4?

On the 320, you need to use our converter, and set the EFIS to format 1.

As for the OAT, being stuck at 13C is pretty odd. In any case, the fact that it reacts to being plugged and unplugged indicates that EDC is working fine. Because of this, it's probably the OAT that is either mis-wired or damaged. It sounds like you'll need to give us a call so we can check on a few more things and send you a new OAT if needed.

 

[millerwse]

Setting the format to 4 corrected my perceived Transponder problem.

After your response to the OAT, I "zeroed" the sensor. Ambient air was about 26 deg C and indication was about 12 degree C. I changed the outside air temperature and indications changed.

Problem statement:
Initial indication is more than 10 C below ambient and correction is beyond the calibration range.

 

[dynonsupport]

Well, then this is probably just a sensor type issue. Do you have the sensor type set to "1" or "2"?

It should probably be "2". We stopped shipping type "1" sensors about 18 months ago, so if your sensor is new-ish, it's a "2".

 

[millerwse]

The selection is 2
1 gives an "OAT not found"
N is a manual setup

 

[dynonsupport]

Just to be clear - does the indicated temperature change at all if the sensor is heated or cooled?

 

[millerwse]

Yes it will change
But I have not seen an increase - only a decrease.
and again not more than 3 degrees C.
I can test anything you want but the indication is about 20 degrees low and beyond the calibration limits of the Dynon.

 

[millerwse]

Should I call?

 

[dynonsupport]

You're welcome to call - 425-402-0433 is where you can reach us.

A few other things to check:

Does your OAT have red/blue/yellow wires AND a small band of black heat shrink tubing near the sensor end?
With power off, what is the resistance between the red and the yellow wires? Between the yellow and the blue?
With power on, what is the voltage between the red and the blue, and between the yellow and the blue? And what is the OAT value during all of these measurements.

Finally, double and triple check that the 3 wires are making it back to the right pins on the EDC-D10A. If any of them are off or wired incorrectly, you're going to see some funny readings.

 

[millerwse]

Not a solution but the end had a black band as cautioned in the installation instructions.
I'll check again but another guy verified wiring last time I "double" checked it. I'll check it again and maybe we"ll all laugh.

You gave me some points to check - what are the resistances and voltages considered normal?

 

[millerwse]

I see from other posts that
20c = 12.5 K
30c = 8 K

before I take it apart, have you any second thoughts? Surely this is not the first case of this type.

Less downtime if I purchased a new one known to work to install.

 

[dynonsupport]

Honestly, the type 2 OATs fail very rarely, and we don't want you to spend $65 unnecessarily. Once we get those resistance values from you we can figure out if there is anything wrong with your probe.

 

[millerwse]

Haven't had a chanch to have the plane down long enough to remove and test.
FYI "zero" gives 13D C when ambient is about 30. Increase in altitude will get indication down to 9 or so (set on 13 on ground)
whatever

 

[millerwse]

Removed and inspected wiring - found I had made a bad connection....(Multiple splice to pin 1)
Corrected and instrument works well.
Thanks for the support - this is my first airplane