Fuel tank indications

[Oscar Avalle]

Well, I have been observing something really strange and I have been trying to figure out what is going on... but I can't. I replaced my analog fuel sensors with digital CIES ones. They worked great. But lately they indicate well when everything is off. But as soon as I turn on the alternator the fuel indication goes down on my JPI 900 from full to 3/4. Any idea what may be going on? some grounding perhaps...

Thank you

Oscar

[carusoam]

Let’s call in the big gun at @fuellevel….   (Odd change well after installation… Ceis fuel level sensors…)

Best regards,

-a-

[Oscar Avalle]

On 3/8/2022 at 10:44 PM, carusoam said:

Let’s call in the big gun at @fuellevel….   (Odd change well after installation… Ceis fuel level sensors…)

Best regards,

-a-

I did call, As usual they are great. It seems that the issue is a ground, either of the alternator and/or the JPI. THis could also be related to the ASPEN...They are working on it and hopefully I get some good news...

[Oscar Avalle]

Well, it seems that the problem has been solved. I had some avionics done and that had somehow impacted the way the senders were working. So I recalibrated the senders and they are working again. 

[tim417]

I envy you and your CIES sensors. Just another item on my want list. 

[Marauder]

I envy you and your CIES sensors. Just another item on my want list. 

I was one of the early Mooney adopters of the CiES senders. There were some hiccups getting the JPI stuff to work with the senders. Once they were resolved, the accuracy of the gauges are phenomenal. I actually trust them.

The only thing better would be if JPI would display the tenths digit on the amount in the tank. The JPI rounds what you are on the display. So when you see 26 gallons, it could be 26.4 or 25.6. If you download the actual raw data from the JPI, it will show the actual amount with the tenths digits. Bob Belville clued me into this because I was whining how it was off a gallon.

And if you have your k factor dialed in, there should be no doubt how much fuel you are using.


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[RobertGary1]

6 hours ago, tim417 said:

I envy you and your CIES sensors. Just another item on my want list. 

I had this option and opted to just overhaul my existing senders. I figured they made it 50 years last time I’ll get another. 50 now. 

[carusoam]

Some people use their Fuel level indicators for different reasons…

If you want 1gal level accuracy… go Ceis!

If you’re fine with 1/8th of a tank level accuracy… and like the old analog gauges… stay analog!

An eighth of a 26 gallon tank is 3+ gallons… and accuracy of reading it adds to the error…..

 

The problem I had with the mechanical gauges in my older Mooney… they needed to be OH’d desperately…. 

I carried way more fuel than needed to avoid running out…

 

Having a fuel totalizer changes the game as well…

Having a fuel totalizer and Ceis Fuel level systems…

You are always going to know your fuel status… even if you develop a leak…. Mid flight…

PP thoughts only, not a mechanic…

Best regards,

-a-

[Mikey30V]

On 3/20/2022 at 12:55 AM, Marauder said:

I was one of the early Mooney adopters of the CiES senders. There were some hiccups getting the JPI stuff to work with the senders. Once they were resolved, the accuracy of the gauges are phenomenal. I actually trust them.

The only thing better would be if JPI would display the tenths digit on the amount in the tank. The JPI rounds what you are on the display. So when you see 26 gallons, it could be 26.4 or 25.6. If you download the actual raw data from the JPI, it will show the actual amount with the tenths digits. Bob Belville clued me into this because I was whining how it was off a gallon.

And if you have your k factor dialed in, there should be no doubt how much fuel you are using.


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Do you have the "voltage" or "frequency" CiES sensors?

 I have a 1975C model with a JPI 900 that is operating with the OEM sensors in "voltage" mode but is apparently capable of either sensor mode.  Below about 10 gallons/side, the sensors are getting a little "notchy" and hesitating to decrease their output with the falling tank levels.  

Edited March 29, 2022 by Mikey30V

[Marauder]

Do you have the "voltage" or "frequency" CiES sensors?
 I have a 1975C model with a JPi 900 that is operating with the OEM sensors in "voltage" mode but is apparently capable of either sensor mode.  Below about 10 gallons/side, the sensors are getting a little "notchy" and hesitating to decrease their output with the falling tank levels.  

Mine are running frequency mode. The JPI 900 does require a specific firmware version and a cable to run in frequency mode. The OEM senders can only run in resistance mode. You’ll need CiES senders to run frequency mode.

The CiES senders are rock solid all through the fuel capacity range. Before I installed the CiES senders, I would get a full mismatch error periodically with the OEM senders.


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[Mikey30V]

30 minutes ago, Marauder said:

Mine are running frequency mode. The JPI 900 does require a specific firmware version and a cable to run in frequency mode. The OEM senders can only run in resistance mode. You’ll need CiES senders to run frequency mode.

The CiES senders are rock solid all through the fuel capacity range. Before I installed the CiES senders, I would get a full mismatch error periodically with the OEM senders.


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Thanks; I've been trying to decide voltage vs. frequency for the CiES ever since I started getting Fuel Mismatch and Low Fuel warnings on a round trip from EVV to Gulf Shores earlier this month.  The totalizer was spot on for fuel consumption at the end of both trips.  The JPI 900 displays the option to select Voltage or Frequency in configuration mode, so unless JPI tells me that they need the unit (new August 2018) back to the factory, I ought to be OK.  Frequency Mode it shall be for 30V!

[Marauder]

Thanks; I've been trying to decide voltage vs. frequency for the CiES ever since I started getting Fuel Mismatch and Low Fuel warnings on a round trip from EVV to Gulf Shores earlier this month.  The totalizer was spot on for fuel consumption at the end of both trips.  The JPI 900 displays the option to select Voltage or Frequency in configuration mode, so unless JPI tells me that they need the unit (new August 2018) back to the factory, I ought to be OK.  Frequency Mode it shall be for 30V!

I don’t remember when JPI made frequency mode as part of the standard configuration. When I installed my CiES senders, the JPI would not support frequency mode. I had to send the unit back for a firmware update and for them to send me the required cable.

I started a thread on MooneySpace that went through my CiES/JPI adventure. Frequency mode is the way to go. Very stable.


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[carusoam]

JPI caught on slowly… after every one had to go back to the factory… to get updated for frequency mode…

New JPI900s should have the skill to be changed in the field… this change came a few years ago…(?)

So….

If you use resistance mode… you get a really good system with JPI/Ceis… better than the ship’s gauges….

If you use frequency mode… you get the 0.1 gallon accuracy… which is more than the whole system can be held to….

in other words… frequency is as good as it gets… but you can’t really count on the 0.1 gal accuracy for several other reasons…

PP thoughts only, not a mechanic…

We have the Ceis guy around here if you have questions…

Best regards,

-a-