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Capacitive Senders with G3X and wiring

snoop9erdog

Well Known Member
For those of you using a g3X and needing capacitive fuel senders, did you go with the Princeton or another model of sender? The manual calls out Skysports or Westach also.

The wiring diarams of the GEA 24 call out the senders to be powered thru the GEA 24. Is this correct? No 3 amp CB for each sender and wired directly to the buss?

What have others done in regards to Cap senders and the G3X?

Thx
 
Steve G3Xexpert got with me and got me squared away.

If it helps anyone....most transducers are powered by the GEA24, however the manual calls for the higher power hogs such as the Princeton to be wired to ship power. See Steve's response below. Hope this helps others.

________________________________________
Ed,

Yes, the Princeton convertors are known for needing more power than the 50 mA highly regulated transducer power outputs are designed to supply, but this is not a problem since they can typically run off aircraft power.

Even though you are wiring power and ground to the Princeton module, you might still run both the ground and signal wire from the Princeton module to the GEA 24 just to make sure everything is at the same ground reference.
 
Princeton

I spent quite a bit of time talking to Princeton about the senders that I have for my -10.

From what they explained to me, the Princeton capacitive sensor will work just fine with the garmin and it does not need the converter, which is another of their products...

Apparently, there is a bit of confusion about the Princeton capacitive sending units and the Princeton converter for capacitance systems...
 
Pix

The pix I have of the bent senders is in mykitlog.com...

Search for Sunman, IN....I am the only one building here.

The senders were purchased from Princeton and they were pre bent for the -10. They install in the same location as the float sensors. I opted for the two point system. People are going to say that they will not be accurate when the tanks are full due to the dihedral. This is true but I would rather have them accurate near empty than near full. The floats suffer the same issue.

I will try and locate the pix and post a link...
 
pix

Hey, I can't get to the workshop until Saturday for the pix.

If you go to mykitlog.com, search for me in Sunman Indiana, you will find my complete build log.

Goto the wings section and the page detailing the senders, with pix, will be the first entry...5-3-2013.
 
I put the Princeton probes in my 10. Very accurate after you use the first 7 gallons or so due to wing angle. That being said, after my Phase 1 fly-off, I started using auto fuel and sometimes a mix of auto fuel and 100 LL. That threw off the calibration so on my 9A, I used the float senders instead.
 
.....I started using auto fuel and sometimes a mix of auto fuel and 100 LL. That threw off the calibration so on my 9A, I used the float senders instead.

I was thinking about using the Princeton?s as well on my -7 project and I was going to do a 50/50 blend of Avgas and MoGas when it came time to do the calibration to try and strike a happy medium. I?ve since decided to just go with the standard floats. I?ve heard that the quality of the standard floats have improved, so hopefully I?ll get many years of trouble free service out of them.
 
Multi-point senders talking G3x

I can use some help. Has anyone successfully interfaced the Princeton multi-point fuel senders to talk to teh Garmin G3x system?

I've reached out to Todd/support at Princeton over email but am having some difficulty reaching them. I'm kind of in a bind as my panel is apart so I could program these senders, and I'd like to try and button things up so I can close this chapter of troubleshooting and move on. I'm going to email Steve/G3xpert and see if they can help as well. In the meantime...

I have the multi-point senders (5 points) from Princeton. According to Princeton, it seems many of the common EFIS units use only the 1 point setting version. I'm not sure if the multi-point senders will work with the Garmin G3x touch system. Do I have to do something else to calibrate the Garmin to the Princeton senders? Maybe what I need to do is to set an empty point and then set all the other points at full? Any ideas?

Thank you in advance.
 
I can use some help. Has anyone successfully interfaced the Princeton multi-point fuel senders to talk to teh Garmin G3x system?

I might be able to help as I just finished calibrating the Princeton senders on my RV-7. Mine are two-point but the process is similar. Can you tell me which RV you’re building and which capacitive plates/probes you’re using?

Dave
 
I also plan to use the Princeton 2 point converters with Vans capacitive plates.
I was unaware of the power issues when using them with GEA 24, do any other builder experience with this combination would be helpful.
 
I also plan to use the Princeton 2 point converters with Vans capacitive plates.
I was unaware of the power issues when using them with GEA 24, do any other builder experience with this combination would be helpful.

Bjorn,

That’s exactly the configuration that I have and I had no problems powering the converters from the GEA-24.

I’m not sure which Princeton probes/converters Garmin refers to in the G3x install manual as consuming too much power. I measured the current draw of my 2-point converters and they only draw 8 ma, well below the GEA-24’s limit of 50 ma.

Everything worked as advertised when I calibrated the senders and G3x using Princeton’s and Garmin’s instructions.

HTH

Dave
 
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possible...

I spoke with Todd at princeton some time back about this. I think part of the confusion is that princeton makes capacitance SENSORS and they also make a capacitance CONVERTER/INTERFACE.

After speaking with him, it was apparent that the sensors (the black puck with the tube that goes in the tank) does NOT need a converter; it outputs a variable voltage based on the capacitance sensed. This output works just fine with the GEA24.

The CONVERTER/INTERFACE is to be used when you use a home rolled setup, usually with plates in the tank. This black box converts a variable capacitance to a variable voltage to be used with the GEA24, and may require more power than the GEA24 can reliably provide.

I have corresponded with several people that are using the princeton sensors with the GEA24 without any issues...

Look at the probe sensors and converters here:

https://www.princeton-electronics.com
 
The CONVERTER/INTERFACE is to be used when you use a home rolled setup, usually with plates in the tank. This black box converts a variable capacitance to a variable voltage to be used with the GEA24, and may require more power than the GEA24 can reliably provide.
Hello Bob,

While it is true that some of the Princeton converters require more power than is available from the highly regulated +12V transducer power outputs on the GEA 24, we have never heard of this being a problem since these converters all seem to be capable of being powered directly from aircraft power.

Thanks,
Steve
 
thanks!

Yes, I guess I wasn't clear.

My point was that the Princeton sensor probes seem to work fine with the G3X system and a converter is not necessary...

Thank you for your input!
 
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