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prkaye

Well Known Member
I am preparing the values for configuring my Dynon EMS - i.e. setting the colour ranges.
The engine manual for my O-320 gives the maximum, desired and minimum (where applicable) values for oil temp, oil press, fuel press, CHT etc, but I'm unsure what to use for my yellow caution ranges.
Can anyone point me to a set of standard values for these yellow caution ranges for engine instrument markings for an O-320?
 
Good question. I'd think initially you'd want some higher thresholds to prevent unecessary distractions (false alarms) on that first flight.
 
I would think that not hooking up the voice would be a good idea on phaseI. Just have a yellow light on the panel for EMS warn. That's what I did. I did have a situation on first flight, the alternator field blew and left me with no charging, the yellow light came on and I went to the ems section of the dynon and found the alternator was not working, in turn the radio went out, didn't transmit. I was circling over the airport and the tower knew I was on first flight. I did a quick stall check in the downwind and lowered the flaps, this in turn got the towers attention because I was at 3500ft circling and went into the pattern, after a couple tries to reach me they noticed I had the flaps down and cleared me to land. A non event, but still if I had all the sounds blairin' it would have been a big distraction. Oh and the fuse was too small 5 amps needs to be higher for the planepower alt. I also went to a resettable fuse for that location.
 
I'm not so worried about htat. I have a single switch on my panel that will cut EFIS power if I run into a problem with alarms freaking me out. I have backup steam gauges (which I will probably be using as my main gauges for first flight anyway) for Airspeed and Altitude.
I'd still like to get my EMS ranges correctly colour-coded, so that when I'm monitoring things I can easily see that "things are in the green", as well as have some advance warning before I get to the critical levels. I'm just not sure where the yellow arc should start for some of these values - i.e. at what values I should start to be concerned (but not freak-out).
It's too bad the Dynon doesn't have seperately configurable alarms for the yellow and red ranges (i think there's only one alarm for any time you go out of the green).
 
Phil -

Have you got a POH sitting around for a Piper or Cessna that uses a Lycoming? The engine won't know what airframe it's in, so the yellow ranges given for those would be fine starting points for things like oil pressure and temperature....

Paul
 
Have you got a POH sitting around for a Piper or Cessna that uses a Lycoming?
Click to expand...

Yes, that's a very good idea. I actually did start doing that from an old C172 (N-model), but I wasn't able to find some of the ranges in the manual. But I'll do a wider search including some otehr manuals to put some numbers together.
 
A good starting point for color band markings...

...is Van's Accessory Catalog (web based). I had the same initial thoughts on where to set the green/yellow/red bands on my AFS engine monitor. Van's steam gauge pictures gave a good representation of the values for these marking ranges. You will probably refine some of these values as you read the break-in and nominal operating conditions for the particular engine you have chosen for your aircraft.

Air speed color bands (various Vspeeds) are airframe dependent, and Van has published a PDF of this information in the download section on their web site.
 
...is Van's Accessory Catalog (web based).
Click to expand...
Another good idea!

I'm not worried about the airspeed ranges... for my backup gauges I have Vans' airspeed indicator which comes with the bands already marked for me.
 
Here is my thinking. Adjust to your situation and preferred units:

Oil temp Max may be around 250 deg F. Do not be be surprised if the oil temp is above 200 on initial flights. Consider making the yellow arc from 210 to 230 and red above 230. Obviously if it gets to 231 you are not going to die but it gives you a heads up to react before getting to the real upper limit.

CHT max may be 500 deg F (VERIFY). Personally I would stay well below that. CHT also may be high on the first flights. So perhaps the yellow range is 410-440 deg F and red above 440.
 
Ron Lee said:
... Do not be be surprised if the oil temp is above 200 on initial flights...
Click to expand...

For the initial flight, I highly recommend you turn off all the audio alarms except maybe low oil pressure.

You will be focused on that EMS for the first few flights so you don't need the audio alarm going off in your ear to distract you even more.

On my first flight, the oil pressure would go into the red on short final and send the audio alarm off just as I was getting into the flair. Not real good timing. (I had to add some washers to the oil pressure valve spring, no screw adjuster on my old engine.)
 
Temp/pressure range limits

Phil,

Gil Alexander summed up the limit ranges in the following thread (o-360). Same limits should apply to the o-320, but you may want to customize.... use this as a starting point.

http://www.vansairforce.com/community/showthread.php?t=23130

I'm reposting the limit ranges here as well from the above thread (I think this should be a stickie somewhere)....
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...
​
 
Alfio,

I agree with all of your numbers and they match both my O-290-D2 and O-360.

But I have never seen or read this one:
Lycosaurus said:
...
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.
...
Click to expand...

I'm not saying you are wrong or anything but it has been my understanding that you can run any Lycoming at 75% power until TBO without any problem.

Mahlon, or anyone else wish to comment?
 
Anyone have suggested range bands for volts and amps?

Volts (regular PC 680 battery, fed with the Plane Power 60A alternator):
lower red =
lower yellow =
green =
upper yellow =
upper red =

Amps (My shunt is located in Dynon's position C, and per a Nuckoll's diagram, which means it's reading alternator output, 0-60A):
lower red =
lower yellow =
green =
upper yellow =
upper red =
 
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