Percentage of Power bug

[Steveden]

I've got a single Skyview touch and a ECI Titan 340, 180hp in my cub. I can't figure out why and how to fix the percentage of power # indicator. Currently it reads very low, for instance, at 2350 rpms which is 65% power, it's reading only 40% power. Has anyone had this issue? Is there a way to adjust this, I can't find anything in the manuals.

 

[DBRV10]

You need to set the engine HP in the engine section, drill through the setup menu's.

You also need a valid OAT, valid MAP and fuel flow.

And do not assume any given MAP/RPM = X% because when ROP this is true but when LOP it will be fuel flow dependent. The algorithm sometimes gets confused at the point of crossover so you can get a PK or ROP when in fact you are LOP.

Dig into the manual and read up some.

 

[kellym]

I've got a single Skyview touch and a ECI Titan 340, 180hp in my cub. I can't figure out why and how to fix the percentage of power # indicator. Currently it reads very low, for instance, at 2350 rpms which is 65% power, it's reading only 40% power. Has anyone had this issue? Is there a way to adjust this, I can't find anything in the manuals.

Since I believe that is a 180 hp rated engine, you may need to tell the system that it is a Lycoming O-360 to get correct readings.

 

[Steveden]

You need to set the engine HP in the engine section, drill through the setup menu's.

You also need a valid OAT, valid MAP and fuel flow.

And do not assume any given MAP/RPM = X% because when ROP this is true but when LOP it will be fuel flow dependent. The algorithm sometimes gets confused at the point of crossover so you can get a PK or ROP when in fact you are LOP.

Dig into the manual and read up some.

Thx David,
Yes, I have been digging I've done all required inputs on the engine setup menu (type, brand, hp, etc), calibrated fuel flow, OAT sensor is working but I still get the same low reading. Is there a way to actually change/adjust numbers somewhere in the menus to get it to read properly?

 

[DBRV10]

Steve........you can cheat by adjusting the engine HP, but if it really is that wrong you have something wrong. These things just work. But I am sure you know the BIBO concept. So something is BS, somewhere.

 

[Dynon]

Just FYI, the horsepower number in setup is really a misnomer. We tried to make it easy to understand, but it should say something like "adjustment factor". IE, don't be worried if you need a number lower than the HP that you know you're making to get the percentage to work out. Starting with your believed HP is good, but you may need to go up or down from there, depending. And even if you end up at a lower number, it doesn't mean you're not making that power.

 

[Steveden]

I've tried changing the HP # but it doesn't do anything. I'm going to go thru all the connections, I may have a loose connection on something somewhere. Not a real big deal and It's really not something I use much, just wanted it to read correctly.

 

[DBRV10]

If all the inputs required exist it should work.

 

[kellym]

If all the inputs required exist it should work.

I agree. If you lean to LOP on all cylinders, and set throttle so that fuel flow is 7.8, you should be at 117 hp or 65%
Because for your normally aspirated engine, fuel flow times 15.0 will equal horsepower. That horsepower divided by 180 gives you percent power.
I know when I am on engine as 1/2 screen, both percent power and actual horsepower are displayed. At 10 gph, my settings and airspeed match with expected 150 hp. (I have 260 hp engine, so 150 hp is below 65%)

 

[RVDan]

Once you have verified the setup, you can start by verifying that all of the required inputs are accurate. If MAP, OAT, RPM or Pressure Altitude are in error, the resultant % of power will be also. In particular the location of the OAT probe is important so that it isn’t seeing hot air from the engine.

 

[Steveden]

Thanks RVDan, I'll check it all out.