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Percent power config

Posted: Fri Oct 25, 2013 2:47 am
by kwiatkma
Next question! How do I enter percent power information for my engine (O235-F1) into the HXr so that it will start to give me percent power calculations? I think I've found the required info via lycoming, but don't know the procedure to enter it into the HXr.

Thanks!

Re: Percent power config

Posted: Fri Oct 25, 2013 3:35 am
by Bobturner
Look at the HX set up guide, chapter 6, especially 6-5 (bottom) thru 6-7. I'll bet the HXr is similar.

Re: Percent power config

Posted: Wed Oct 30, 2013 6:25 pm
by katieb
Yep, most things in HX are programmed the same way in HXr.

Here is an excerpt from the HXr Graphical Engine Display setup guide I'm working on. Should be posted online by the end of this week. I will send you a copy now if you want a draft. It presents the setup in a more step-by-step order with some diagrams and worksheets to help you figure out where to put everything.

To program HXr with the performance data for your engine:
1. Press MORE > Set Menu > Engine Limits
2. Scroll to Engine Performance and press the knob to access the Engine Performance table.
3. Enter the values for your engine based on the engine manufacturer’s documentation. The left side contains entries for the manifold pressure values representing 55% power and 75% power at sea level. The right side contains values for the change in horsepower (delta) for each increment of altitude. Estimated horsepower value charts for common engines are also located on the GRT EIS documentation web page. Use the engine manufacturer’s documentation whenever possible for the best accuracy.

Re: Percent power config

Posted: Sun Nov 03, 2013 2:40 am
by kwiatkma
Bob and Katie,

Thanks, I've found the entry point and was uploading all my engines data this afternoon. The amount of information is just amazing. Just when I think I'm done I find another item to configure and give me real time information that I can use to make me a better pilot.

Re: Percent power config

Posted: Tue Nov 05, 2013 2:24 am
by saybeengineering
And another excuse to go flying and test the inputs!!!!! :D :D :D :D :D :D

Re: Percent power config

Posted: Tue Nov 05, 2013 5:00 pm
by katieb
Speaking of features... I uploaded the HXr Graphical Engine Display Setup Guide this morning: http://grtavionics.com/HXr%20Engine%20I ... lement.pdf It doesn't go into detail about wiring and setup of the EIS, but when you set all the limits in the HXr instead of the EIS, it does make life easier.

I will put a Manifold Pressure sensor on my airplane with a fixed-pitch prop just to avoid having the --- above the Percent Power and SFC calculations! (They are always up on the ENG/MAP screen whether you use them or not.) It will be fun to mess with those numbers. To think of all the time I flew around in old certified airplanes without giving a rip about percent power, cylinder head temps and EGT, leaning the engine til it rattled then nudging it back in to find the best mixture at altitude, and using my watch and a dipstick between flights as the sole means of determining the fuel flow rate... UGH! Dark ages!! If I did that again, it would be like flying with one eye covered up, one ear plugged and no sense of smell.

Re: Percent power config

Posted: Sat Nov 16, 2013 9:04 pm
by Widget
I found all the charts for my engine and loaded all the info into the HXr and now I know all there is to know..well, maybe..at least what my engine is doing..

Katie, I did have to go back and fly round gauges and such for a while and it was horrible.. except that I was flying.

I'm absolutely amazed at how much I missed my HXr and all it's situational awareness. So glad to be out of the dark ages again.

Re: Percent power config

Posted: Sat Nov 16, 2013 10:47 pm
by Bobturner
Just remember that the data out is no better than the data (table) in, and the data table is for one mixture, best power. At other mixture settings the actual power will be less than indicated. Error is only a few (like 4%) percent between peak EGT and full rich. If you run lean of peak, where power becomes approximately proportional to fuel flow, the error gets larger.

Re: Percent power config

Posted: Wed Nov 20, 2013 1:25 am
by kwiatkma
OK so I entered my data and the percent power is showing an odd number...I get 640% power and at full throttle 999% power. Do I need to setup a decimal point somewhere?

It seems like the correct calulation for percent power...just a a decimal point off. For instance 640% power if I do my math correctly is really 64% power. When I put in full throttle it shoots up to 999% power but should be 99.9% or maybe it rounds up to 100%!?!

So when I cruise around at 75% cruise my percent power says 755% power....so close!

Re: Percent power config

Posted: Wed Nov 20, 2013 2:29 am
by GRT_Jeff
In the SET MENU, Graphical Engine Display settings, scroll down to the Aux Function settings and check the MAP Integer/Decimal setting. It should be set to Decimal.