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Setting EMS Values - How Determined?

lrfrey

Well Known Member
I'm in the process of setting values for my Dynon EMS, ie Red/Yellow/Green values for things like oil pres, oil temp, cht's etc.

I know how to set them, and I know what the Low, High and Normal values are, these can all be gotten from Lycoming etc.

The question is what values do I use for the Green/Yellow areas spefically. Some percentage of total?

For instance, assume max is 100 min is 20. Above 100 is obviously Red and below 20 is Red. What's Greeen/Yellow? Green 30 to 90, Yellow in between?

Is there some general rule to follow?

Thanks, Larry
 
A starting point

I'm in the process of setting values for my Dynon EMS, ie Red/Yellow/Green values for things like oil pres, oil temp, cht's etc.

I know how to set them, and I know what the Low, High and Normal values are, these can all be gotten from Lycoming etc.

The question is what values do I use for the Green/Yellow areas spefically. Some percentage of total?

For instance, assume max is 100 min is 20. Above 100 is obviously Red and below 20 is Red. What's Greeen/Yellow? Green 30 to 90, Yellow in between?

Is there some general rule to follow?

Thanks, Larry

Larry... it depends on the parameters and your safety margins....

I was calculating the same thing..... generic Lycoming O-360 carb version

OIL TEMPERATURE

Upper Red 245F - Lycoming Operators Manual figure

Upper Yellow 220F - 245F - based on desired temp. of 170F plus margin and Lycomings engine life numbers below...

Green 75F to 220F - see VAF discussion on the lower number - some folks prefer 100F - 220F range

No Lower Yellow area

OIL PRESSURE

Upper Red 115 psi

Yellow upper 95 to 115 psi - this for starting and take-off only

Green area 55 to 95 psi - normal operating area from Operators manual

Lower Yellow 25 to 55 psi - operating area while idling

Lower Red 25 psi

CYL HEAD TEMP

Upper Red 500F

Upper Yellow 435F to 500F

Green area 150F to 435F - the 150F is my number, Lycoming gives no lower number, but 150F is really cold for a CHT....:)

FUEL PRESSURE (carb)

Red upper 8 psi - check this, it is from my memory...:)

Green area 0.5 psi to 8 psi

Red lower 0.5 psi - no yellow for this parameter....

This is a good starting point - in general, I think you want the red to activate alarms, and yellow to be a warning (non-audible)

NOTE - the CHT numbers are high - this is what Lycoming says....

8. For maximum service life, maintain the following recommended
limits for continuous cruise operation:
a. Engine power setting — 65% of rated or less.
b. Cylinder head temperatures — 400˚ F. or below.
c. Oil temperature — 165˚ F. — 220˚ F.


After break-in, and experience in your plane, you might want to set the CHT numbers lower for your specific installation...






gil A
 
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Larry,

My settings are close to Gil's. The difference being the numbers in the Lycoming POH for the O-290. Call Lycoming and order the manual for your engine, even if it is a clone.

The other day I was re-reading the manual and noticed Lycoming states not to exceed 500 degrees :eek: CHT and for longer engine life they recommend keeping the CHT's below 400 for continued operation. Again, these numbers are for my O-290.

Thus my CHT numbers are:
Lower Red 450F & Audio alarm

Upper Yellow 400F to 450F

Green area 150F to 400F - I don't remember where I set my low numbers but 150 sounds good...

FYI - for your first flight, turn most of the audio alarms off or set them high. Keep low oil pressure on where it should be. There is nothing more distracting than those audio alarms when you are already keeping your eye on the displays.
 
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EMS parameters for 0-320?

Time to set up my D180. Does anyone have recommended numbers for a vertical draft carbed 0-320? I'm assuming they'll be close to the numbers
Gil provides for the 0-360, but I'm not sure. My engine came new from Aerosport but I can't find any recommended parameters in the paperwork. I'm especially interested in appropriate break-in numbers as well as I know some things will be running hotter than normal.
Thanks.

Larry... it depends on the parameters and your safety margins....

I was calculating the same thing..... generic Lycoming O-360 carb version

OIL TEMPERATURE

Upper Red 245F - Lycoming Operators Manual figure

Upper Yellow 220F - 245F - based on desired temp. of 170F plus margin and Lycomings engine life numbers below...

Green 75F to 220F - see VAF discussion on the lower number - some folks prefer 100F - 220F range

No Lower Yellow area

OIL PRESSURE

Upper Red 115 psi

Yellow upper 95 to 115 psi - this for starting and take-off only

Green area 55 to 95 psi - normal operating area from Operators manual

Lower Yellow 25 to 55 psi - operating area while idling

Lower Red 25 psi

CYL HEAD TEMP

Upper Red 500F

Upper Yellow 435F to 500F

Green area 150F to 435F - the 150F is my number, Lycoming gives no lower number, but 150F is really cold for a CHT....:)

FUEL PRESSURE (carb)

Red upper 8 psi - check this, it is from my memory...:)

Green area 0.5 psi to 8 psi

Red lower 0.5 psi - no yellow for this parameter....

This is a good starting point - in general, I think you want the red to activate alarms, and yellow to be a warning (non-audible)

NOTE - the CHT numbers are high - this is what Lycoming says....

8. For maximum service life, maintain the following recommended
limits for continuous cruise operation:
a. Engine power setting — 65% of rated or less.
b. Cylinder head temperatures — 400˚ F. or below.
c. Oil temperature — 165˚ F. — 220˚ F.


After break-in, and experience in your plane, you might want to set the CHT numbers lower for your specific installation...






gil A
 
The only differences I can find for the O-320 is that the max oil pressure cold and take-off is 100 psi and normal operation max= 90 psi, and a slightly higher normal minimum pressure of 60 psi

CHT is the same.

Oil Temp same.

Fuel Press same for a carb.

The O-320-D2J does have a different oil pressure spec.

I would use these to start --

OIL PRESSURE

Upper Red 100 psi

Yellow upper 90 to 100 psi - this for starting and take-off only

Green area 60 to 90 psi - normal operating area from Operators manual

Lower Yellow 25 to 60 psi - operating area while idling

Lower Red 25 psi
 
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Bringing back an old thread here, but I am currently setting up my Skyview.

Can anyone recommend EGT settings for an O-360-AIA
 
Absolute EGT is not very important. EGT trends are. The only important EGT number might be 1500 degrees F as that is when bad things start hapening to the exhaust system.
 
Mike Busch Video

I would suggest watching some of Mike Busch's vides on the EAA video player website. He has a fairly extensive dicussion on the newer EMS systems, his preferences on how to set the temps (specifically on CHTs), and how he uses the logging features to diagnose problems. Excelent way to spend an hour.
 
Personally, I set my Dynon CHT with the yellow starting at 400 and the red at 430. My thinking is that if my CHT gets to 400 I want to start doing something to correct it. I also feel that the Lycoming 500 degree limit is way too high for engine longevity.
 
CHT numbers

Personally, I set my Dynon CHT with the yellow starting at 400 and the red at 430. My thinking is that if my CHT gets to 400 I want to start doing something to correct it. I also feel that the Lycoming 500 degree limit is way too high for engine longevity.

The numbers I used above are Lycoming's absolute limits.

It is probably better to use their recommended limits instead -

For maximum service life, cylinder head temperatures should be maintained below 435?F (224?C) during high performance cruise operation and below 400?F (205?C) for economy cruise powers.

From the O-360 manual here -

http://www.yukonflying.com/Documents/Lyc 0perating Manual.pdf
 
My #3 CHT sometimes reaches ~450 on warm days on initial climb - stays there until the nose is lowered (after reaching the obstacle clearance alt,) then settles between 330 - 360 during cruise @59 - 62% power depending on OAT. I've heard so many opinions on whether this is detrimental to the engine. The Lycoming guys at SnF said don't worry, it's well within design parameters. Who to believe....
 
The Lycoming guys at SnF said don't worry, it's well within design parameters. Who to believe....


Hmmmm....the guys sitting around the hanagr in the evening with indeterminate backgrounds....or the guys with all the engineering data and expereince?;)
 
Hmmmm....the guys sitting around the hanagr in the evening with indeterminate backgrounds....or the guys with all the engineering data and expereince?;)

Or....the owners who've shelled out good money for premature failures, or the employees whose livelyhood depends on selling cylinders?

I will never accept 450 CHT.
 
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The only thing I would add to that is that you should have a yellow alert for your oil temperature from as low as it can go to 100?. You are in Illinois and Gil is in Arizona. We need to wait for our oil to get to 100 degrees before takeoff. I have a yellow alert on my Garmin screens until I reach take off temperature. You might want to do the same?

:cool: CJ
 
The only thing I would add to that is that you should have a yellow alert for your oil temperature from as low as it can go to 100?. You are in Illinois and Gil is in Arizona. We need to wait for our oil to get to 100 degrees before takeoff. I have a yellow alert on my Garmin screens until I reach take off temperature. You might want to do the same?

:cool: CJ
Sound like a good idea. Here in Texas during the summer the warning will go off quickly while in the winter it'll remind us not to run-up or take-off before the engine is warm enough. Thanks .
 
According to who?

+1

I have always chuckled at this one. What does a 100* minimum oil temp have to do with the ability to run an engine at 2700 RPM without damage or wear? Minimum CHT, I get. Minimum barrell temp, I get. Min/max oil pressure, I get. However, I have seen no data (or even warnings from knowledgeable OEM engineers) to indicate that with an oil temp of 90 you will harm your engine by running at 2700 RPM. I would think differently if we were spinning 6000 RPM.

Even Lycoming says as long as it will take full power without hesitation, you are good to go. No mention of min oil temp.

Yes, the oil needs to be a reasonable temp in order to flow and not create excessive pressure. This varies with oil type, but that min temp is WAY below 100*.

Personally, I wait until my CHTs get to about 230+ and have been there 1-2 minutes (to allow barrels temps to catch up to CHTs), then I am good to go. I would have to wait another 10 minutes for the oil to get to 100 with all other critical temps remaining exactly the same.

There is a good reason to give your steel and aluminum parts a chance to reach reasonable operating temps and expand. However, Oil lubricates just as well at 60* as it does at 100*. Oil temps GREATLY lag those of the critical metal parts, especially at low RPMs, after a cold start and therefore a poor indicator for engine warm up.

In fairness, if I was running 100 weight oil (aviation 50) in the Midwest winter I would establish a higher minimum oil temp to ensure that it will flow and not create excessive pressure before applying full power. However, no one should be doing that and I certainly don't. Maybe that's where this advice came from. Least common denominator advice that will protect from all potentials.

Larry
 
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This thread is a reminder to me that we (the collective) are easily led to be slaves to our displays instead of the masters. The configuration options provided by the MFD vendors are there to HELP YOU, not enslave you. Aside from some well established "hard" limits, the rest should be up to you. If you cant think up an intermediate "soft" reminder color to help foot stomp a value, then its probably not worth going to the internet to try learn that behavior.

Make the displays work for you, and if that means turning a feature completely off, then do it.
 
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