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G3X Nav System Interconnect Diagram. Please critique
- Thread starter danlh
- Start date
I think your question(s) about the ELT are covered in this recent thread: https://vansairforce.net/threads/artex-345-remote-pinouts.232131/. And I think you want to ground the GTP59 OAT probe locally (well, I'm using my chassis for ground so that's what I'm doing).
I asked Garmin about the G5 connectivity -- based on this answer I'm not wiring RS232.
Everything looks good to me.
I asked Garmin about the G5 connectivity -- based on this answer I'm not wiring RS232.
Everything looks good to me.
I didn't check your pin numbers, but it looks like you have some ARINC 429 TX versus RX confusion between your GAD 29 and GTN 750.
An RS-232 interface between your GTN 750 and your G5 is indeed optional, but for various reasons I would connect it if given the opportunity, which you certainly have. Do this by connecting the RX pin on the G5 to the same TX pin on the GTN 750 that is being used for the MapMX format.
An RS-232 interface between your GTN 750 and your G5 is indeed optional, but for various reasons I would connect it if given the opportunity, which you certainly have. Do this by connecting the RX pin on the G5 to the same TX pin on the GTN 750 that is being used for the MapMX format.
Thanks Kirk. My question on the ELT is with the Serial connection. In their drawing they show a wire going from the ELT RX Pin which I am running to GTN650 RS 232 TX. They also show a ground which is not attached to anything. I was wondering how I handle that ground.
Yes, I did have a mis type on the labels. I double checked the pin numbers and they wor good. Thanks for catching that.
I have a questions about the G5 RS-232 connection. In the G5 manual it shows the same pin numbers that I used which are RS-232 #3. It also indicates any available RS-232 connections would be acceptable. Then it goes on to say configure mapmx format 2 or mapmx. My question is can multiple RS-232 ports be configured as mapmx?
Thanks Mike.
I think that you would like to have MapMX from the GTN to the GDU (PFD) allso.
RS 232 from the GTN to the GDU (PFD) and then a jumper to the G5. This works well.
G3X, IM, rev AW, pdf pg: 443.
When MapMX data is received, the G3X display can show more accurate information about
the external navigator flight plan (e.g. DME, arcs, and holding patterns).
Good luck
RS 232 from the GTN to the GDU (PFD) and then a jumper to the G5. This works well.
G3X, IM, rev AW, pdf pg: 443.
When MapMX data is received, the G3X display can show more accurate information about
the external navigator flight plan (e.g. DME, arcs, and holding patterns).
Good luck
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What does MaxMX give you on the G5? Right now (flying RV-10) I have a G5 but it is completely detached from the G3X system so I might be missing context for what the G5 would use the MapMX data for.
The way I interpret their drawing is that you run one 3-conductor, shielded cable from the avionics to the ELT. One wire is RS232 out from the GTN. The other two wires connect to the panel switch. On the avionics end, the shield connects to the RS-232 ground pin on the GTN. On the ELT end, the shield connects to pin #7 (ground) which also should be connected to the chassis ground.
Redundancy, and there is data available via the MapMX connection which is not available via ARINC 429. It's not a required connection, but if you are doing a new installation, the cost of one extra wire is as close as it gets to free in aviation.
Refering to the G5 IM, rev 10, pdf pg 81 and the G3X IM, rev AW, pdf pg 443.
As I understand the G3X IM, connection to a GTN and GAD29 is optional, not that MapMx is optional when G3X is connected to GTN and GAD29.
Holdings and DME arc's (curved leg types) will not be displayed without MapMx.
In experimental it's up to the builder. The STC'd version Part 23requires MapMX.
Good luck
As I understand the G3X IM, connection to a GTN and GAD29 is optional, not that MapMx is optional when G3X is connected to GTN and GAD29.
Holdings and DME arc's (curved leg types) will not be displayed without MapMx.
In experimental it's up to the builder. The STC'd version Part 23requires MapMX.
Good luck
That's correct, the MapMX RS-232 connection is required for a G3X system, so if your GTN is navigator #1 and you're already connecting something to that RS-232 port, there's no good reason not to connect it to the G5 as well.
So, in terms of RS-232 data coming out of the GTN I think this sums up the best practice for a new installation, correct?
- MapMX from GTN to GDU PFD (bi-directional)
- CONNEXT from GTN to GDU PFD (bi-directional)
- Position data from GTN to ELT (one-way)
- MaxMX from GTN to G5 (one-way)
Originally I tried using the symbol editor to make the boxes with pins but that was a problem when I needed to change pin and connector positions for certain placements. Right now I’m creating them on the schematic as I need them. I’m open to suggestions of a better way though.
Dan
My question about formating more than 1 RS-232 ports to Mapmx wasn't answered directly, but judging from comments made, it looks like the answer is no.
So I will jumper the G5 RX-232 RX to the same GTN R-232 TX pin as the one going to the GDU. Thank you everryone. I believe I've got all my questions answered.
Dan
Edit: Actually, there is one more question. The G5 interconnect drawing (G5 IM PDF pg 72 shows a 3 wire shielded cable with the wire from RS-232 TX pin 5 not terminated. I was wondering why they don't show a 2 wire cable.
So I will jumper the G5 RX-232 RX to the same GTN R-232 TX pin as the one going to the GDU. Thank you everryone. I believe I've got all my questions answered.
Dan
Edit: Actually, there is one more question. The G5 interconnect drawing (G5 IM PDF pg 72 shows a 3 wire shielded cable with the wire from RS-232 TX pin 5 not terminated. I was wondering why they don't show a 2 wire cable.
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Ahh I missed that possibility. If that's true then it is a bit confusing that the MapMX to the GDU is shown as 2-way but to the G5 is shown as one-way. So are you going to set up transmit/receive between the GDU and GTN and then only connect the TX (from GTN) to the G5?
That was my thinking.
As I understand it the MapMx RS232 from GTN to GDU is bidirectional (TX/RX) but from the GTN to the G5 is one way (TX) only.
The GTN sends ARINC 424 (TX) curved leg types to both the GDU and the G5.
From the GDU it is possible to optionally output (TX) frequency tuning data and receive (RX) radio (GTN) status data for on-screen radio display.
There is no information going from the G5 to GDU or GTN. The G5 is only receiving (RX) from the GTN.
Good luck
The GTN sends ARINC 424 (TX) curved leg types to both the GDU and the G5.
From the GDU it is possible to optionally output (TX) frequency tuning data and receive (RX) radio (GTN) status data for on-screen radio display.
There is no information going from the G5 to GDU or GTN. The G5 is only receiving (RX) from the GTN.
Good luck
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