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GRT settings for a newbie

comatb

Member
Question about 'cruise oil pressure'. Today was the first time we started up the new GRT Horizon 10.1 and did a taxi test. We got an alarm saying 'cruise oil pressure low' when we pulled the throttle back to idle during the runup. Why does the GRT assume I'm in cruise when there is no airspeed? How can I keep this alarm from happening every time I pull back to idle? (I have an RV-6 with a Lycoming 0-320.)
 
First option:
In the setup menu, turn off all alarms until you know you have everything functioning accurately and reliably.

Second option:
In the setup menu, change your “low cruise oil pressure” setting to some low number that will keep it from going off.
 
Do you have the GRT EIS set to give alarms? If so, you need remove them.

The alarms need to be set on the 10.1 Horizon only. The data from the EIS is a one way street, and you can not cancel the EIS generated alarms from the Horizon.

You could set the alarms in the EIS, and not the Horizon but then you need to cancel them in the EIS.

Way easier to set alarms in the Horizon and cancel them from it.

Been there, done that.
 
Mike, I have a slightly different take on that. My EIS boots up seconds after engine start, while my EFIS takes longer. If I have no oil pressure a few seconds after start, I want to know it without delay.
I generally programmed the EIS to turn on the red light if something was so bad it needed immediate attention. e.g., oil pressure zero, EIS alarms. Oil pressure below the bottom line but not zero, efis alarms. Same thing for CHT: over 425 F efis alarms, over 435 F EIS alarms. Ymmv of course.
 
RVbySDI, why does the GRT have an additional Minimum cruise oil pressure, if it's not aware that I'm not in flight? Does it assume flight according to RPM or airspeed? If it's RPM, can I adjust that? I see Minimum RPM, but again, that would set off alarms every time I check IDLE on a runup. Seems kind of counter intuitive to set everything to 0 and lose the alarm function.
 
Thanks, Mike S. I assumed the EIS and the EFIS were talking to one another - that anything I set in one would change the other. Thanks for letting me know that that is not the case.
So - are you saying to set everything to 0 in the EIS, and then set all parameters in the EFIS?
 
In my old grt system, there is a limit called set-lim. If i recall, there is an associated low pressure limit. Works like, when rpm is above set lim, but pressure is X , alarm. The thought is to catch low cruise oil pressure.
 
Thanks, Mike S. I assumed the EIS and the EFIS were talking to one another - that anything I set in one would change the other. Thanks for letting me know that that is not the case.
So - are you saying to set everything to 0 in the EIS, and then set all parameters in the EFIS?

That, or set critical stuff like min oil pressure and max CHT in the EIS like Bob said----he is one of the GRT wizards of VAF. The red alarm light is controlled by the EIS.

I personally have the min oil pressure still in the EIS so it does control the red alert light. I feel the light is more likely to be noticed than a bar graph on the EFIS.

I also have a dual battery setup that gets the panel lit up prior to, and through engine start so I have all engine readouts going before I push the START button.
 
I generally programmed the EIS to turn on the red light if something was so bad it needed immediate attention. e.g., oil pressure zero, EIS alarms.

Yep, I have the same. But at this time only the oil triggers the warning light

Oil pressure below the bottom line but not zero, efis alarms. Same thing for CHT: over 425 F efis alarms, over 435 F EIS alarms. Ymmv of course.

I think I may steal this idea. Thanks :D
 
RVbySDI, why does the GRT have an additional Minimum cruise oil pressure, if it's not aware that I'm not in flight? Does it assume flight according to RPM or airspeed? If it's RPM, can I adjust that? I see Minimum RPM, but again, that would set off alarms every time I check IDLE on a runup. Seems kind of counter intuitive to set everything to 0 and lose the alarm function.
Be aware that I am not telling you to turn all of these alarms off permanently. I am saying to turn them off until you know exactly how your engine/airplane performs, sounds, feels, etc. Until you, as the pilot, KNOW how to fly your new airplane. You DO need to monitor your readings closely but you need to do so without the distractions of lights and/or aural alarms. Then once you have all that, study how you need to go into the settings and set the parameters where YOU know what those settings need to be.
 
Question about 'cruise oil pressure'. Today was the first time we started up the new GRT Horizon 10.1 and did a taxi test. We got an alarm saying 'cruise oil pressure low' when we pulled the throttle back to idle during the runup. Why does the GRT assume I'm in cruise when there is no airspeed? How can I keep this alarm from happening every time I pull back to idle? (I have an RV-6 with a Lycoming 0-320.)

Per the EIS manual: You need to set an entry for min RPM which corresponds to min cruise power. Then the alarm will sound if oil pressure is lower than the cruise min entry and rpm is greater than min cruise power. If your engine manufacturer doesn’t recommend one, just make it the same as min oil pressure.
 
Max/Min/Min Cruise Oil Pressure

The GRT EIS has three entries for oil pressure. Max/Min/Min Cruise. For my engine, I use 90 for the max; 60 for min cruise and 25 for minimum (as recommended by Titan). I was having the same problem when I was taxing - ie getting the alarm at idle when the pressure was fine (above 25psi but below 60 psi).

By the way - the only alarm I left ON in the EIS was oil pressure (EIS connected to an EFIS). I want every alarm blarring if I lose oil pressure. It's also good during start-up since the EFIS takes a while to boot.

Dave
Woodbridge, VA
RV-8 Flying

I should have read everything. Like Bob said; the "Lim-RPM" will define when RPM limits become active. Set this value to an RPM where you want the "Crz-OP" to become active. Below the Lim-RPM number only the Min-OP alarm (in my case 25 psi) is active. GRT suggests setting the Lim-RPM to a value below the MAG check so all the RPM dependent alarms are "awake" during run-up.
 
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Dave, you mentioned you 'had' the same problem. Did setting 60 for min cruise solve the problem while taxiing or idle after runup?
I still haven't understood why the system does not recognize that I am not in flight from the airspeed and thus sets off the alarm below 60?
Thanks for any advice.

The GRT EIS has three entries for oil pressure. Max/Min/Min Cruise. For my engine, I use 90 for the max; 60 for min cruise and 25 for minimum (as recommended by Titan). I was having the same problem when I was taxing - ie getting the alarm at idle when the pressure was fine (above 25psi but below 60 psi).

By the way - the only alarm I left ON in the EIS was oil pressure (EIS connected to an EFIS). I want every alarm blarring if I lose oil pressure. It's also good during start-up since the EFIS takes a while to boot.

Dave
Woodbridge, VA
RV-8 Flying

I should have read everything. Like Bob said; the "Lim-RPM" will define when RPM limits become active. Set this value to an RPM where you want the "Crz-OP" to become active. Below the Lim-RPM number only the Min-OP alarm (in my case 25 psi) is active. GRT suggests setting the Lim-RPM to a value below the MAG check so all the RPM dependent alarms are "awake" during run-up.
 
Dave, you mentioned you 'had' the same problem. Did setting 60 for min cruise solve the problem while taxiing or idle after runup?
I still haven't understood why the system does not recognize that I am not in flight from the airspeed and thus sets off the alarm below 60?
Thanks for any advice.

In this instance, the EIS doesn't use airspeed. It uses RPM (not all EIS's have the airspeed option). Oil Pressure is one RPM dependent alarm (Low Volts is another, I think). So you have to set an RPM limit to activate (or deactivate) the RPM dependent alarms. So.... for oil pressure, there are three entries. Max/Min/Idle (for me - 90/60/25psi). The EIS uses the RPM trigger to determine if an alarm should sound below 60 or below 25. So as an example - If the RPM limit is set to 1500rpm, if the rpm is below 1500 only the 25psi limit will trigger an alarm (taxiing). Above 1500 (flying) the 60psi becomes the dominant pressure to trigger the low OP alarm (tho the 25psi will still trigger an alarm even above 1500rpm - but the 60psi alarm would already have alerted)
Feel free to give me a shout at 703-254-4267 if needed.
Dave
 
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