Thoughts on Panel Upgrade Ideas

[g3xpert]

Originally Posted by jamesdavid

I have been pouring over the Garmin install manuals for the G3X, GNC375, and GNC255 trying to figure out how this all fits together to achieve the second option in my original post (G5, G3X, GNC255, GNC375).

Any thoughts on this high level diagram (am I forgetting any connections / hooking this up in the best way)?

Thanks again, Everyone.
James

Hello James,

Your diagram looks pretty good! Just a couple of comments on the GNX 375 installation.

1. The GNX 375 receives altitude data directly from the GSU 25 ADAHRS, so it is not necessary to install the GAE 12 altitude encoder on the back of the unit or connect the static line.
2. The bi-directional RS-232 connections from the GNX 375 to the PFD are MapMX and Connext as shown on page 27-35 of the Rev. AL G3X Installation Manual.
3. There is an EFIS/Airdata A429 connection from the GAD 29 to the GNX 375.
4. There is only the single GPS A429 connection from the GNX 375 to the GAD 29.
5. Any additional GDU 4XX displays in your system will have a Connext RS-232 connection to the GNX 375 so that they may receive ADS-B Traffic/Weather.

Thanks,
Steve

[jamesrw2002]

Hey James,

What you're doing and what I'm doing is somewhat similar. Are you doing the harness yourself or are you going to outsource it?

Originally Posted by jamesdavid

I have been pouring over the Garmin install manuals for the G3X, GNC375, and GNC255 trying to figure out how this all fits together to achieve the second option in my original post (G5, G3X, GNC255, GNC375).

Any thoughts on this high level diagram (am I forgetting any connections / hooking this up in the best way)?



Thanks again, Everyone.
James

[jamesdavid]

Steve / g3xpert,

Thank you so much for the quick and detailed response here! Very helpful! Updated diagram based on your feedback.

Regarding your point 1. Is there any benefit to using the GAE 12 in addition to the GSU 25?



Best,
James

Originally Posted by g3xpert

Hello James,

Your diagram looks pretty good! Just a couple of comments on the GNX 375 installation.

1. The GNX 375 receives altitude data directly from the GSU 25 ADAHRS, so it is not necessary to install the GAE 12 altitude encoder on the back of the unit or connect the static line.
2. The bi-directional RS-232 connections from the GNX 375 to the PFD are MapMX and Connext as shown on page 27-35 of the Rev. AL G3X Installation Manual.
3. There is an EFIS/Airdata A429 connection from the GAD 29 to the GNX 375.
4. There is only the single GPS A429 connection from the GNX 375 to the GAD 29.
5. Any additional GDU 4XX displays in your system will have a Connext RS-232 connection to the GNX 375 so that they may receive ADS-B Traffic/Weather.

Thanks,
Steve

[jamesdavid]

James,

The wiring harness I am somewhat confident that I could do well (I have an electrical engineering degree). I am more concerned about metal fabrication and finish for the new panel. The original builder did a great job and I want to make it look just as nice.

Originally Posted by jamesrw2002

Hey James,

What you're doing and what I'm doing is somewhat similar. Are you doing the harness yourself or are you going to outsource it?

[g3xpert]

Originally Posted by jamesdavid

Steve / g3xpert,

Thank you so much for the quick and detailed response here! Very helpful! Updated diagram based on your feedback.

Regarding your point 1. Is there any benefit to using the GAE 12 in addition to the GSU 25?

Best,
James

Hello James,

You are very welcome.

There are some places around the world that require that the transponder used in the ATC system be certified and use a certified pressure altitude source.

For those rare instances, the certified GAE 12 pressure sensor provides a means for those installations to be compliant.

Most of us vastly prefer that the GSU 25 ADAHRS that is providing data to the primary flight display also provide altitude data to the transponder.

Having a single air data source should also make it less expensive to complete the periodic transponder check.

Thanks,
Steve

[jamesdavid]

g3xpert / Steve,

Some additional questions came up as I have been reading more of your other threads and the install manual.

Any benefit to:

• GNX 375 / G5: Adding an additional MapMX connection from the GNX375 to the G5? I saw this post in another thread:
  
  

  “We recommend you connect the MapMX serial interface from the much higher capability GTN 625 to the G5 serial port input like shown on page 62 of the Rev. C G5 Installation manual. Note that this same GTN serial output is also connected to the PFD. With this installation, you could turn off both the GDU 460/470 displays and still fly an autopilot coupled LPV approach with the GTN 625 and G5, and of course fly an autopilot coupled flight plan entered on the GTN anywhere you like.” http://www.vansairforce.com/communit...d.php?t=148601

• GNC 255 / GAD 29: Adding an ARINC connection to the GAD 29 from the GNC 255 (in addition to the RS-232 connection to PFD1)? (Would this put the VOR/ILS information on the CAN bus, since I have the GAD 29 for the GNX 375, should I use it with the GNC 255 also, or should I just use the RS-232 connection for the GNC 255?)
  
  
• Thinking Ahead for PFD2 ... If I Wire a Connector for PFD 2, and then do not install the PFD, will everything continue to work without issues (e.g., CAN bus wont break without a node at the connector) but allow for me to add in a PFD2 at a later time?

To Everyone,

• Regarding Lighting Bus. Do people doing an all Garmin panel find that using the photocells work well, or should I plan to wire up a lighting bus based on what people have experienced in the real world?

[rchrds]

Can someone drop a link to the GNX 375 installation manual please? I can't find it on the Garmin site.

Thanks!

[fl-mike]

Because it is not on the site, or anywhere on-line. Not sure why, but it is not.

[jamesdavid]

Now that I know the big-ticket items, I am trying to figure out the best way to organize switches and breakers. This is what I have come up with. Apart from the general layout, some of the specific questions I still have are:

• Should I put the GAD 29 on the Avionics bus, or the Main Bus? It is only needed for the Avionics (GNX 375 and GNC 255), but other examples placed it on the Main bus...
• I have a breaker and a switch for the GAP 26 Pitot Heat. Any reason not to just use a Switch Breaker?

Thoughts and input appreciated...

[Jim Frisbie]

Where is your CO detector.?
Essential!