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Pitot heat discrete

Anybody use the garmin pitot heat discrete-blue wire? I don?t see where it gets wired to in the schematics. GAD27 or GEA 24?
 
I?m not quite there yet, but I?ve run the discreet from the wing. So far this is what I?ve found. The G3X Touch manual is not entirely clear if the GAD 27 will provide every option that the GEA 24 discrete will provide with the GAP 26. I?m assuming it will, given that one if the advertised functions of the GAD 27 is to add a bunch more discreets, but not 100% sure.

From the G3X manual:

?The discrete output (bare blue wire) from the control box (011-02965-00) can be connected to any available discrete input. The discrete output is floating (open-circuit) when the probe is powered off, or when powered on and below 25? C. When the probe is above 25? C and powered on, the discrete output will be shorted to ground. See GAP 26 Alert Configuration (-20 version only).?

?If the discrete output (bare blue wire) from the control box is connected to one of the EIS discrete input pins on the GEA 24 or GSU 73, the status of the GAP 26 heater can be displayed in one of three ways (following), depending on user preference:

1. The discrete input configuration shown in Figure 35-51 will result in a green "PITOT HEAT" indication that will appear on the PFD any time the GAP 26 heater is powered and the probe temperature is above approximately 25? C (77? F). If pitot heat is powered off or inoperative, the green "PITOT HEAT" indication will not appear.

2. The discrete input configuration shown in Figure 35-52 will result in a yellow "PITOT TEMP" alert that will appear on the PFD any time the GAP 26 heater is powered off, or if it is powered on but the probe temperature is below approximately 25? C (77? F). If pitot heat is powered and the probe temperature is sufficiently high, the yellow "PITOT TEMP" alert will not appear.

3. The discrete input configuration shown in Figure 35-53 will result in a yellow "PITOT TEMP" alert that will appear on the PFD similar to Configuration #2, with additional logic that automatically prevents the yellow "PITOT TEMP" alert from appearing if the outside air temperature is above approximately 7? C (45? F). This configuration provides the same indication as Configuration #2, but hides the pitot temperature alert when flying in warmer weather conditions.?
 
Discrete

The gea24 has four discrete pins available, however, you can use some of the GP pins for additional discretes if you aren?t using them. It?s a bit more involved when using the gp pins but not bad. This is what I did. I have not lowered up yet but according to the manual, it should work.

The GAD27 gives you ten additional discrete inputs, I think. I did not use the GAD27 as I am using a vpx and their functions basically overlap.
 
Sorry, I opted for the non-regulated heated pitot, so no need for the blue discrete wire. Regulated pitot heat is a nice option but I just worried about magnetometer interference issues that I read about in the forum.
 
Sorry, I opted for the non-regulated heated pitot, so no need for the blue discrete wire. Regulated pitot heat is a nice option but I just worried about magnetometer interference issues that I read about in the forum.

Why would it not be needed? You still want to know that pitot heat is on and working, I think.
 
GAP 26 Discrete Output

I?m not quite there yet, but I?ve run the discreet from the wing. So far this is what I?ve found. The G3X Touch manual is not entirely clear if the GAD 27 will provide every option that the GEA 24 discrete will provide with the GAP 26. I?m assuming it will, given that one if the advertised functions of the GAD 27 is to add a bunch more discreets, but not 100% sure.

From the G3X manual:

?The discrete output (bare blue wire) from the control box (011-02965-00) can be connected to any available discrete input. The discrete output is floating (open-circuit) when the probe is powered off, or when powered on and below 25? C. When the probe is above 25? C and powered on, the discrete output will be shorted to ground. See GAP 26 Alert Configuration (-20 version only).?

?If the discrete output (bare blue wire) from the control box is connected to one of the EIS discrete input pins on the GEA 24 or GSU 73, the status of the GAP 26 heater can be displayed in one of three ways (following), depending on user preference:

1. The discrete input configuration shown in Figure 35-51 will result in a green "PITOT HEAT" indication that will appear on the PFD any time the GAP 26 heater is powered and the probe temperature is above approximately 25? C (77? F). If pitot heat is powered off or inoperative, the green "PITOT HEAT" indication will not appear.

2. The discrete input configuration shown in Figure 35-52 will result in a yellow "PITOT TEMP" alert that will appear on the PFD any time the GAP 26 heater is powered off, or if it is powered on but the probe temperature is below approximately 25? C (77? F). If pitot heat is powered and the probe temperature is sufficiently high, the yellow "PITOT TEMP" alert will not appear.

3. The discrete input configuration shown in Figure 35-53 will result in a yellow "PITOT TEMP" alert that will appear on the PFD similar to Configuration #2, with additional logic that automatically prevents the yellow "PITOT TEMP" alert from appearing if the outside air temperature is above approximately 7? C (45? F). This configuration provides the same indication as Configuration #2, but hides the pitot temperature alert when flying in warmer weather conditions.?

The discrete output from the Regulated GAP 26 can be connected to any available discrete input in the system. This is an overview of the 3 options you have to control the behavior of the Pitot Heat indications.

1. Green PITOT HEAT CAS message if:

a. Pitot Heat is powered, and the probe temperature is above 77F.

Settings:
i. Input type set to Active Low
ii. Input Function Set to User-Defined Alert
iii. Alert Color set to Green
iv. Alert Label set to PITOT HEAT

2. Yellow PITOT TEMP CAS message if:

a. Pitot heat is powered off

OR

b. Pitot Heat is powered on and the probe temperature is below
77F.

Settings:
i. Input type set to Active High
ii. Input Function set to User-Defined Alert
iii. Alert Color set to Yellow
iv. Alert Label set to PITOT TEMP

3. Yellow PITOT TEMP CAS message if:

a. Pitot Heat is powered off and OAT is less than 45F. *If OAT is
greater than 45F, the CAS message is suppressed.

OR

b. Pitot heat is powered on, and the probe temperature is below
77F.

Settings:
i. Input Type set to Active Low
ii. Input Function set to Pitot Temp

Thanks,

Justin
 
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