What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

G3X Power On / Off

How do you turn a G3X on and off?

Hello Andrew,

A G3X or G3X Touch is typically a large system consisting of many devices like ADAHRS, servos, transponder, etc.

Most of the devices have dual power inputs, and to turn off something like a GDU 460 display, you have to switch off both the power 1 and power 2 inputs, if both are used.

Thanks,
Steve
 
I suspect the more succinct answer is... with the aircraft master switch.

Or at least that's how many aircraft are wired, so one doesn't have a switch that would allow you to accidentally power down your primary flight display while in flight.

As Steve mentioned, the multiple power inputs on the G3X allow for it to be powered from multiple sources (like the main bus and an Essential or Endurance bus). It's up to the individual aircraft builder to determine the architecture of their aircraft electrical system, and from that design will flow the methodology for powering the various pieces of avionics. All that to say, each amateur-built aircraft is likely to be a little bit different, so the answer to your question is somewhat unique to the aircraft in which the equipment is installed.
 
I just had to giggle a little at the "interpretation". Actually, I wondered that as well when I was installing my panel and a wise friend explained that this is part of a system and the avionics master is the switch.
 
Oohhh...

These explanations cover the how and the why. I really do appreciate it! Thanks for taking time to better understand the G3X system.
 
When designing your panel and electrical system, you should also think about how/when you might want to power down individual components in the system.

We recently worked with a customer who wanted to practice shutting down the primary flight display and flying the plane with the battery powered G5 backup flight instrument.

This is a great thing to practice, but this customer had no way to shut down the PFD except to shut down the alternator and open the battery contactor!

We don't recommend opening the battery contactor in flight except in an emergency, so you should provision for a panel switch or at least a pullable circuit breaker for anything you even think you might want to power down for practice or selective load shedding in a power emergency.

Thanks,
Steve
 
Steve, I can't say how much I appreciate the support you guys provide. After 2 years with my avionics, I still get stumped and need help, you all are there and always offer timely and helpful advice. Thank you!
David
 
Steve, I can't say how much I appreciate the support you guys provide. After 2 years with my avionics, I still get stumped and need help, you all are there and always offer timely and helpful advice. Thank you!
David

You are very welcome, David.

Thank you so much for your kind words. We have the greatest customers!

Steve
 
For those designing panels, there are some key concepts in this discussion that should not be overlooked - in particular the need/desire to power off individual components. With multiple power inputs, it can get trickier than just a switch or breaker. Many of the boxes (G3X or GTN) do not have an on/off switch (master functions as that). However, I have never met a computer (and these are sophisticated computers) that didn?t some time in its life ?lock up? and require a reboot. For that reason, I made certain I could ?power off? each box less dramatically than cycling the airplane master. This also has become useful during software and database updates because I can power only the device I?m updating rather than the whole panel during the rather lengthy update process. (To Garmin?s credit, while I have had a screen lockup on the G3X Touch, the unit recognized the issue itself and rebooted on its own, so I have not had to power down for this reason. Also, there is a ?3-button salute? reboot a-la Windows that will restart a unit, but it is not described in the manuals.)
 
Or, for simulating partial panel, just cover up the PFD, Navigator, etc and let your safety pilot have full instrumentation.
 
My avionics master(s)

Control the avionics buss, but each pc. of equipment in the plane has a pullable circuit breaker --- in the case of the 650/430 each requires more than one breaker (nav, com, cdi).

The breakers make if very easy to trouble shoot or isolate. I know some folks try to minimize the number of breakers --- I pretty well maximized mine.

Ron
 
Control the avionics buss, but each pc. of equipment in the plane has a pullable circuit breaker --- in the case of the 650/430 each requires more than one breaker (nav, com, cdi).

The breakers make if very easy to trouble shoot or isolate. I know some folks try to minimize the number of breakers --- I pretty well maximized mine.

Ron
True but some of the avionics has redundant power lead and unless one has both power leads thru CB this is not easily accomplished. In my case the aux TCW feed the second lead and the passthru wires will keep the equipment energized even if I switch its master off. I am planning on putting a relay on TCW so I can shut all power to the TCW battery with one toggle switch
 
True but some of the avionics has redundant power lead and unless one has both power leads thru CB this is not easily accomplished. In my case the aux TCW feed the second lead and the passthru wires will keep the equipment energized even if I switch its master off. I am planning on putting a relay on TCW so I can shut all power to the TCW battery with one toggle switch

Bavafa,

Why not just eliminate the pass thru function of the TCW rather than place a relay? Or would it have been better to wire like that (eliminate passthru) in the first place? Asking because I'm finalizing my wiring with the TCW IBBS and wondering what the real value of the passthru is if the IBBS is a last resort backup power in a complete main buss electrical failure.

Upon startup you have the IBBS switch on to test the IBBS backup system and ensure that it is functioning.....with the passthru, how do you know you are testing only the independent IBBS system??
 
Bavafa,

Why not just eliminate the pass thru function of the TCW rather than place a relay? Or would it have been better to wire like that (eliminate passthru) in the first place? Asking because I'm finalizing my wiring with the TCW IBBS and wondering what the real value of the passthru is if the IBBS is a last resort backup power in a complete main buss electrical failure.

Upon startup you have the IBBS switch on to test the IBBS backup system and ensure that it is functioning.....with the passthru, how do you know you are testing only the independent IBBS system??

IBBS test: MASTER OFF, IBBS ON
PASSTHROUGH test: IBBS OFF, MASTER ON
 
Bavafa,

Why not just eliminate the pass thru function of the TCW rather than place a relay? Or would it have been better to wire like that (eliminate passthru) in the first place? Asking because I'm finalizing my wiring with the TCW IBBS and wondering what the real value of the passthru is if the IBBS is a last resort backup power in a complete main buss electrical failure.

Upon startup you have the IBBS switch on to test the IBBS backup system and ensure that it is functioning.....with the passthru, how do you know you are testing only the independent IBBS system??

Contemplating this same thing now.
With IBBS passthru you would have to pull a GDU breaker and pull the 10A IBBS breaker to reset a GDU? Almost seems like the passthru is defeating the purpose of the GDU breaker to begin with.
Let alone, seems like a single point of haywire if the IBBS battery were to decide to make trouble?

Might S/C the passthru wires we installed.
 
Back
Top