Garmin EIS 275 - data logging with G5

[xywh]

I just installed a Garmin GI 275 EIS in my Piper Pacer. Love it so far. The other avionics I have in my plane are dual G5s and a GPS500W (like a GTN530W with no Nav). The GI 275 is not connected to either of these (I know I can connect to GPS, but I don't think to G5?).

One of the things I want to do with it is download the engine data and play with it (I'm an analytics guy), and also send it to Savvy Aviation for analysis. However, the data output from the EIS 275 right now is lacking important data - namely, altitude. I'd also love to have lat/long, orgin/destination, etc. - but altitude is the big one.

I think I could connect the GPS to the EIS and get GPS altitude logged. But, I know that I already get ALL of that data in my G5s. I can throw in an SD card,, and enable data logging, and have all of the G5 data in a separate CSV. It'd be great to just be able to "combine" the G5 data and the EIS 275 data.

So, I think I have several questions:
1. Can you connect the G5 to the GI275 EIS for purposes of only logging data in the EIS related to the G5 (altitude). I don't think I can, per the 275 install manual (don't see any pin outs for G5)
2. If I connected the GPS500W to the GI275 EIS, would I get GPS altitude logged on the EIS? Pretty sure I would...
3. Does anyone have any other ideas on how I could accomplish this? I actually thought about creating a parser to drop the data logs from the G5 and the EIS275 into it, and the parser would combine the two into one datafile based on UTC timestamp... I suppose that would work, but not be elegant.

Thanks!
Chase

 

[nauga]

Lumping all of your questions into one, both the G5 and the GI275 have CAN bus interfaces. The G5 dumps air data (among other things) onto the bus for use by other stuff and logs a crap ton of data from other devices on the bus(*). It wouldn't surprise me at all to find a consolidated log on one of the boxes. Off the top of my head I'm not sure if you need an ARINC429 interface (e.g. GAD29) to make it all work - I have one for other reasons and don't what the logs would look like without it. Probably pretty hard to test in a TC'd airplane but you might dig into the bus stuff and see if it's worth a shot.

*My G5 logs contain a lot of nav data from a GNX375 and a couple of other things on the same CAN bus - I don't need to pull data from any other Garmin box, it's all on the G5 log. I do not have a GI275, tho.

Nauga,
and miles of orange wire

 

[xywh]

Lumping all of your questions into one, both the G5 and the GI275 have CAN bus interfaces. The G5 dumps air data (among other things) onto the bus for use by other stuff and logs a crap ton of data from other devices on the bus(*). It wouldn't surprise me at all to find a consolidated log on one of the boxes. Off the top of my head I'm not sure if you need an ARINC429 interface (e.g. GAD29) to make it all work - I have one for other reasons and don't what the logs would look like without it. Probably pretty hard to test in a TC'd airplane but you might dig into the bus stuff and see if it's worth a shot.

*My G5 logs contain a lot of nav data from a GNX375 and a couple of other things on the same CAN bus - I don't need to pull data from any other Garmin box, it's all on the G5 log. I do not have a GI275, tho.

Nauga,
and miles of orange wire

Thanks a ton! I think I get this. I have an OAT probe that connects to a GAD13 to communicate OAT to the G5s via the CAN bus...

I actually haven't pulled the G5 logs yet, only logs off of the GI275 (which didn't contain any airspeed or navigation data). My G5s, GTX345, GPS500W all "talk" - I assume via CAN bus. Then would be nice if the GI275 was on that as well and perhaps you'd be right. I'll dig in some more. Thanks again!

 

[nauga]

Thanks a ton! I think I get this. I have an OAT probe that connects to a GAD13 to communicate OAT to the G5s via the CAN bus...

I actually haven't pulled the G5 logs yet, only logs off of the GI275 (which didn't contain any airspeed or navigation data). My G5s, GTX345, GPS500W all "talk" - I assume via CAN bus. Then would be nice if the GI275 was on that as well and perhaps you'd be right. I'll dig in some more. Thanks again!

You may already be there
My GNX375 also has logging capability but that appears to be mostly for integrity checking and unit troubleshooting. It pushes a lot more interesting data to the G5. It's convenient in that I only have to transfer Garmin data from one unit, and it's all correlated and common timebase. If only the older Dynon stuff was this easy.

Nauga,
the canary in the data mine

 

[camorton]

The 275 has a built-in VFR GPS. You just have to connect an antenna. It won't log that position and altitude with the engine data?

C.

 

[nauga]

The 275 has a built-in VFR GPS. You just have to connect an antenna. It won't log that position and altitude with the engine data?

C.

But that will be GPS altitude, and for performance numbers like the OP says he wants you need pressure and/or density altitude.

Nauga,
and an air data commuter

 

[xywh]

Reporting back. So, firstly, I didn't realize the GI275 had a VFR GPS built in. I bought an antenna, hooked it up, and yes - now I am supplementing the engine data with GPS data. The problem is that the GPS Altitude field is empty in the entire log - AltGPS is empty. I've googled a bit to see if others have had this experience, but can't find anything. It's logging GPS lat/long, ground speed, track, etc. - but no altitude data. I'm going to attempt to update the 275 and try again.

I threw an SD card in my G5 and went flying tonight. Wow there's a wealth of data in there. Unfortunately, per @nauga 's suggestion - it doesn't look like the data from the EIS 275 is flowing to/from the G5. Seems like maybe if I connect both to the CAN bus? But I don't know. It would be IDEAL to marry these two files together - G5 and 275 EIS.

So that leads me back to hooking up the EIS 275 to the GPS500w in the hopes to at least get GPS altitude?

 

[nauga]

I threw an SD card in my G5 and went flying tonight. Wow there's a wealth of data in there. Unfortunately, per @nauga 's suggestion - it doesn't look like the data from the EIS 275 is flowing to/from the G5. Seems like maybe if I connect both to the CAN bus? But I don't know. It would be IDEAL to marry these two files together - G5 and 275 EIS.

So that leads me back to hooking up the EIS 275 to the GPS500w in the hopes to at least get GPS altitude?

To the best of my knowledge the log sharing is over the CAN bus so if both units are not on the same CAN bus you won't get data from one on the other.
As someone who has done a not-insignificant amount of airplane performance analysis I'll say *I* would go to the trouble of combining and correlating the logs* to get pressure altitude before I would consider trying to do perf analysis with GPS altitude.

*and that's what I currently do with data from a couple of Dynon and Garmin boxes to get consolidated flight logs.

Nauga,
who needs a barometer, not a ruler

 

[xywh]

Really good feedback. Thanks so much @nauga!