I'm adding a GPS 175 to my completed RV-12is. I have a pretty good grasp on the wiring that I need to do but I have some questions that fall in the easy/dumb category. Being an ELSA -12 builder I didn't have to think through the wiring scheme other than the most basic understanding. Garmin's interconnect diagram is very straightforward and I'm inclined to just stick with that, but I have also been making comparisons to the schematics that Van's publishes for the IFR package with the GTX to glean any hints. Van's does a few things different than what Garmin recommends. This is not a big surprise, when ordering and talking with Stein about the addition there was a comment made that they don't like to get too involved in additions to the RV-12 because Van's has done some things that are proprietary but that's it's a fairly simple process. This seems to be true, but I see a couple things I'd like to better understand.
My main question centers around the RS232 (MAPMX and Connext) running to both the PFD and MFD. In the Garmin interconnect diagram these are shown with MAPMX run to the PFD and Connext running to the MFD. This is my plan A, just as their interconnect shows. I understand the "(PFD or MFD)" for the MAPMX implies some flexibility on where that goes. I don't understand whether this is just meant to illustrate a configuration that works for single/double GDU systems in a single drawing, or if there are other reasons to go to each GDU separately for the two protocols.
When I go to the Van's schematic with the GTN it's done a different way. They run the Connext to the PFD, but they split the MAPMX and run that to both the PFD and MFD. The GTN is a different piece of equipment but I'm just looking at the GPS portion.
As I look at things now I feel like I have three obvious choices. MAPMX and Connext both to the PFD, MAPMX/Connext separately to the PFD/MFD each, or splitting the MAPMX to both GDU like Van's does with the Connext only going to the PFD. Would any of the above work, reasons to go one way or the other?
My main question centers around the RS232 (MAPMX and Connext) running to both the PFD and MFD. In the Garmin interconnect diagram these are shown with MAPMX run to the PFD and Connext running to the MFD. This is my plan A, just as their interconnect shows. I understand the "(PFD or MFD)" for the MAPMX implies some flexibility on where that goes. I don't understand whether this is just meant to illustrate a configuration that works for single/double GDU systems in a single drawing, or if there are other reasons to go to each GDU separately for the two protocols.
When I go to the Van's schematic with the GTN it's done a different way. They run the Connext to the PFD, but they split the MAPMX and run that to both the PFD and MFD. The GTN is a different piece of equipment but I'm just looking at the GPS portion.
As I look at things now I feel like I have three obvious choices. MAPMX and Connext both to the PFD, MAPMX/Connext separately to the PFD/MFD each, or splitting the MAPMX to both GDU like Van's does with the Connext only going to the PFD. Would any of the above work, reasons to go one way or the other?
