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NoahF
04-17-2010, 07:42 AM
Planning a two alternator setup where only one alternator will ever be operational (B&C SB1B Regulator on SD-20 aux alternator). Considering running both alternator B-Leads thru the hall effect current sensor and eliminating the weight and connections associated with the shunt. Two questions:

1. Can the GUI be configured to to eliminate the display for the primary current input (shunt) and display only the auxiliary current (hall effect) sensor?

2. Anybody see any issues with this approach?

Thanks!

ArjanPlomp
04-17-2010, 06:06 PM
1) Yes. Go to the calibration page and make sure the shunt reading does not display and the Hall effect does. We are using only the Hall Effect Sensor and it works just fine (on the ground testing only, first test flight with new panel tomorrow (Sunday).
2) No.

NoahF
04-18-2010, 03:54 PM
Thanks Arjan! How did the first flight go?

ArjanPlomp
04-18-2010, 04:40 PM
It was the first flight after the panel upgrade, so it was a little less exciting than a 'true first flight'.

However all went very (actually: extremely) well. A few adjustments here and there (i.e. we used the old Dynon fuel flow sensor which needed a different configuration). The AFS (TruTrak) autopilot is amazing. We had very strong winds and strong turbulence and the AP was 'dead on'. Flew approaches to minimums (in VFR weather for test purposes). My only remark is that 'how to operate the A/P' is poorly documented. I.e. which type of source (turned out to be ARINC) to use for LPV approaches? What sequence to use to start flying an approach? How to fly an ILS from the 430W (still have to figure that out). Also, we have the MAP data and software, but no terrain is displayed on the MAP page (even with 'Terrain On') (I need to debug that and we may simply be missing the terrain database?. How to test if GPSV/GPSS works? The screenshots in the documentation do not apply to the AFS autopilot. They show GPSS/GPSV while I never saw that on my AP, yet it flew GPSS/GPSV perfectly fine.

All in all: very succesful and very impressive first flight. The SV is amazing and paints the runways dead on. When lining up on the runway, even the center line was lining up correctly and the runway numbers were being drawn. Autopilot very impressive also. Again: My only point of criticism is the documentation, but I was already warned about that by a few vendors. If Rob is seeing this: I'm more than willing to provide input to the documentation or provide up to date screenshots and text.

Can't wait to do some more flying behind this panel!

flickroll
04-18-2010, 06:28 PM
we used the old Dynon fuel flow sensor which needed a different configuration

I'll be doing the same thing. What setup did the Dynon fuel flow need with the AFS system? Thanks

ArjanPlomp
04-19-2010, 06:11 AM
Initially it was indicating what I believed was approx half the fuel flow. I changed the setting that was default 680 to 340 for now (don't remember the label name). It seems close and will verify that with actual fuel usage.

What I did notice (and I'm not sure if that is because of the different fuel flow sensor) is that the fuel flow indication on the AFS changes almost once a second and is therefor not very stable and difficult to read. Not sure what effect this will have on fuel flow accuracy. Maybe AFS can respond? Is this because of the different sensor?

ArjanPlomp
04-19-2010, 09:26 AM
Just spoke with Travis at AFS. The value should be between 280 and 310 for correct fuel flow. This makes sense to me. AFS themselves use the same sensor and a value of 280.

flickroll
04-19-2010, 03:46 PM
Thanks. My sensor has a K factor of around 29,000. So the way I understand it my AFS constant would be 290.

I wonder if there's any way to dampen the fuel flow indication... On my Dynon system the FF would vary, but not overly so and using the FF on the D-120 was a good way to go LOP. If the Red Cube would provide a more stable indication I'd change to it. Travis, what do ya think? Thanks

ArjanPlomp
04-19-2010, 03:55 PM
I've started a new thread on this subject. As I have the same problem.

Rob Hickman
04-20-2010, 09:22 PM
The flow scan should work fine with our system.