Using Garmin GPS III Pilot with D120 EMS

[Robski]

I have looked around this and other forums but cannot find anything to say whether a Garmin GPS III Pilot will work with a D120 EMS.

The GPS is my permanently installed backup in my panel, hence wanting to use it! It's an oldie but a goody!.

I have connected the brown tx wire from the Garmin supplied GPS cable to pin 19 of the 37 way d-sub on the D120, and the black negative power line to my avionics central ground point. Both GPS and EMS are set to Aviation, although the GPS calls this "Aviation In".

Should I ground the GPS to an EMS ground?
Should I be using NMEA?
Am I barking up the wrong tree expecting the dinky Garmin to work with the EMS at all? :-?

Any help gratefully received!

 

[dynonsupport]

Sounds like you have it connected correctly - GPS TX to EMS-D120 37-pin connector Pin 19 (AUX Serial RX). Generally connecting both the EMS-D120's ground wire and the GPS ground wire is sufficient for them their grounds to be connected.

Did you ensure that the speeds are set the same - 4800 baud or 9600 baud? Generally setting speed to AUTO on the EMS-D120 works to auto-detect the speed the other unit is transmitting, but not always.

If the GPS input is working, it's subtle to see on the EMS-D120 - mostly the clock gets set automatically, and thus the timestamps in the internal datalog are correct.

I have looked around this and other forums but cannot find anything to say whether a Garmin GPS III Pilot will work with a D120 EMS.

The GPS is my permanently installed backup in my panel, hence wanting to use it! It's an oldie but a goody!.

I have connected the brown tx wire from the Garmin supplied GPS cable to pin 19 of the 37 way d-sub on the D120, and the black negative power line to my avionics central ground point. Both GPS and EMS are set to Aviation, although the GPS calls this "Aviation In".

Should I ground the GPS to an EMS ground?
Should I be using NMEA?
Am I barking up the wrong tree expecting the dinky Garmin to work with the EMS at all?  :-?

Any help gratefully received!

 

[Robski]

If the GPS input is working, it's subtle to see on the EMS-D120 - mostly the clock gets set automatically, and thus the timestamps in the internal datalog are correct.

I thought the GPS was used in conjunction with the fuel flow for working out fuel consumption figures. That's why I connected it.

I will check the baud and other settings again.

Thanks.

 

[Dynon]

You're right - it also does get used for those fuel computer values (like range and mpg).

 

[Robski]

Sussed it out, in case anyone has been following this thread.

I think that a GPS III's 'Aviation in' is just that - in only and not out!
Set both GPS and D120 to NMEA and baud rate to 4800 and the time etc now gets set on the EMS so it must be working.

 

[Robski]

Discovered the GPS gets used by the EMS for something else: altitude.

Without GPS the power figure and LOP / ROP wasn't displayed. It is now.

No EFIS in my system. Yet. Ordered last week!