AX-O

Well Known Member
I posted the following on the GRT board but did not get much feedback. I also called GRT but been playing phone tag with them.

1) I am trying to hook up pin 2 (Audio Tone) on my GRT EIS to a GMA 240. Would I hook GRT EIS pin 2 (Audio Tone) to GMA 240 J1 pin 31 (Alert 1 High) or pin 32 (Alert 1 Low)? If not one of those pins, then which one?

2) Can I use pin 25 (4.8V Excitation Out) on the GRT EIS for multiple
accessories? If so, how do I hook those wires together? Power distribution
block?

3) Can I use pin 13 (12 V floscan) and Pin 14 (Fuel Flow floscan) for a Red Cube fuel meter or are those pins only used for a floscan?

4) The PMAG manual says to use only one PMAG for tach information if you have dual PMAGs. The EIS manual says that "Tach 1" source is used first and "Tach 2" is used if no info is available on "Tach 1". Is "Tach 1" the best source for tach data in this particular configuration?

5) What type of accessories did you guys hook up to Aux1-Aux6?

6) What type of switch did you guys use for selection of EFIS or GPS information to the auto pilot?

Thanks for any help you can provide.
 
I used the ESI 12V out for the Floscan and fuel pressure-sending unit. Aux 1 – L fuel level, Aux2 fuel pressure used the GRT 12v power sending unit, Aux 3 R fuel level, Aux 4 Manifold pressure, Aux 5 Amps.
Squeak
 
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GRT customer assistance ...

You can avoid the phone tag game by emailing Carlos at GRT. It's rare that he doesn't respond within one full business day. He's the EFIS guru there; Sandy answers most of the EIS questions. In the meantime, here's what I recall from Sept when I was wiring mine:
Aux inputs: Sandy told me most builders use Aux 1 for M.P. and Aux 4 for fuel pressure, so I did too. You have to use an aux input (any) for your current sensor and both your fuel tank inputs (any) ... so you'll likely use 5 out of the six available.
4.8V feed : yes, you can use it for multiple sensors. I used a small terminal strip to handle all the 4.8V wiring connections and the %^&*# little resistors (2 for fuel tanks, and 1 for fuel pressure)
A/P selector switch: I used a micro toggle.
Red Cube vs Floscan: you can use the Floscan wiring diagram they give you for the Red Cube .... same color code.
 
Yes you can

Axel,
I just went thru this last month. Like stated above, you can assign Aux's in any order.
Mine are,
1. Fuel press, 2. Amps, 3, L fuel. 4. R fuel, 5, MP. And 6, Stby Batt.

I too, used the 12 v regulated to power warning light, MP pwr, and F Flo. Works great.

I, like Terry used the flo scan. The red cube SF was something in the180-200 rqnge. I'm using 61 on mine and it's dead onfor fuel use don fill ups.

Make sure use have all the Interger/digits assigned correctly. I had a can of worms with fuel gauges until I got that correct. You don't need to put the fuel calibration numbers in the GRT, just do the worksheet provided with the EIS.

The audio is not used on my setup. I'm using a Garmin 240 panel. I was told the audio is for future use.

HOPE THIS HELPS.

PS. I'm absolutely sold on my GRT setup. Auto pilot is smooth and not all that hard to master.
 
Most questions already answered excellently.

I installed a spdt switch to select L or R mag for rpm then use Tach 1 only.

I used 3pdt switch to select AP source.

Definitely use fuel cal worksheet. It got me real close.

Love my GRT HX's.
 
I used all 6 aux inputs, first 5 being fuel left & right, manifold pressure, fuel pressure, amps. 6th to monitor the GRT backup battery.

I talked to Sandy about the EIS audio. Her opinion was to not hook it up, but that if I insisted, to put a switch in the circuit so that when it drove me crazy I could turn it off. Apparently it's not a pleasant sound, and comes on when ever the warning light does.