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New Dynon HDX seeing B/U Battery drain.
- Thread starter dvalle
- Start date
PaulvS
Well Known Member
45 minutes is not enough time to fully charge a new battery. It takes up to 4 hours to fully charge.
Once charged, you can run a test on the ground to verify that the battery is capable of powering the display for 45 minutes, which is the threshold it should be able to pass.
Once charged, you can run a test on the ground to verify that the battery is capable of powering the display for 45 minutes, which is the threshold it should be able to pass.
B/U Battery
Thanks for the replies. Yes, I'm am aware of the B/U battery, how it works, how long of a charge, and battery test. I installed one in a RV6A that I've been flying for about a year.
I've just installed the HDX in a RV9A now and having B/U battery issues. It was fine for about a month then started acting up. I found that it is draining slowly when sitting in the hangar. I've learned a few things, but with the help of Dynon, they decided to try another battery. However, a new battery, after multiple flights that brought it up to full charge, is doing the same thing so hence why I'm asking if anyone has seen this issue.
I also agree, it should not drain as it's only connected to HDX via the Dynon harness and Dynon provided battery connector. I'm thinking the only way it should drain is when you activate the "stay on" or "test battery".
My fear now, maybe something internally to the HDX is causing it. I'm waiting for one of the top support team to get back with me. The AWESOME support team has always been helpful and knows answers to all my questions
Thanks again
Thanks for the replies. Yes, I'm am aware of the B/U battery, how it works, how long of a charge, and battery test. I installed one in a RV6A that I've been flying for about a year.
I've just installed the HDX in a RV9A now and having B/U battery issues. It was fine for about a month then started acting up. I found that it is draining slowly when sitting in the hangar. I've learned a few things, but with the help of Dynon, they decided to try another battery. However, a new battery, after multiple flights that brought it up to full charge, is doing the same thing so hence why I'm asking if anyone has seen this issue.
I also agree, it should not drain as it's only connected to HDX via the Dynon harness and Dynon provided battery connector. I'm thinking the only way it should drain is when you activate the "stay on" or "test battery".
My fear now, maybe something internally to the HDX is causing it. I'm waiting for one of the top support team to get back with me. The AWESOME support team has always been helpful and knows answers to all my questions
Thanks again
PaulvS
Well Known Member
I think your best and probably only realistic option is Dynon support, since the backup battery is fully integrated and controlled by the display. Either there is some unusual parasitic drain, or the system is erroneously detecting a low battery voltage.
My Skyview can sit for weeks without being charged, and even occasional power up via the backup battery, and this has never resulted in a warning message for a low battery.
Good luck, hopefully it is still under warranty and please let us know the outcome!
My Skyview can sit for weeks without being charged, and even occasional power up via the backup battery, and this has never resulted in a warning message for a low battery.
Good luck, hopefully it is still under warranty and please let us know the outcome!
Yes Paul, agree. As mentioned, I have been flying another HDX for almost a year, never any message.
And yes, the battery does drain. To confirm what the HDX voltage is on the B/U battery, I actually unplugged it (for Dynon) and tested when it read not available...it was down to about 4 volts. From what I've learned on the new battery just sent, it will charge up fully on a long flight. In fact, it will charge just by turning on the power if your ship battery power is higher voltage than the B/U battery voltage. Or, if you put a battery charger on that will exceed the amp draw of the HDX, it will charge while turned on. You can see this info under hardware....
I'll post the fix, whatever that may be
Dan
And yes, the battery does drain. To confirm what the HDX voltage is on the B/U battery, I actually unplugged it (for Dynon) and tested when it read not available...it was down to about 4 volts. From what I've learned on the new battery just sent, it will charge up fully on a long flight. In fact, it will charge just by turning on the power if your ship battery power is higher voltage than the B/U battery voltage. Or, if you put a battery charger on that will exceed the amp draw of the HDX, it will charge while turned on. You can see this info under hardware....
I'll post the fix, whatever that may be
Dan
B/U battery drain....resolved!
Very strange and VERY time consuming to resolve...but I am determined when a confronted with the seemingly impossible!
It's a LONG story but I'll jump to the cause.....
The Earth X battery fault when using a LED warning light (as shown on page 22 of the Earth-X manual). I understand from Dynon 1) they were not aware of this issue and 2) they've not heard of any problems when connected to the Dynon HDX for a warning.
If anyone has an Earth-X battery as the ships power and has it set up this way without any issues, appreciate it if you would please share how you have it wired.
Thanks
Dan
Very strange and VERY time consuming to resolve...but I am determined when a confronted with the seemingly impossible!
It's a LONG story but I'll jump to the cause.....
The Earth X battery fault when using a LED warning light (as shown on page 22 of the Earth-X manual). I understand from Dynon 1) they were not aware of this issue and 2) they've not heard of any problems when connected to the Dynon HDX for a warning.
If anyone has an Earth-X battery as the ships power and has it set up this way without any issues, appreciate it if you would please share how you have it wired.
Thanks
Dan
I think you're chasing the wrong squirrel. I've been running an EarthX main ship battery in my 9A with dual Dynon HDX for just over 5 years, have not had this problem, and I've never heard of anyone else having it either.
It's entirely possible you have a wiring issue or internal problem to the HDX that is preventing the normal trickle charge to the backup battery, and it's slowly self-discharging over time.
It's entirely possible you have a wiring issue or internal problem to the HDX that is preventing the normal trickle charge to the backup battery, and it's slowly self-discharging over time.
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Dynon b/u battery drain
Hi Greg
Sorry, maybe not clear. It is resolved in my plane now, the issue is the Earth X battery installed per the Earth X page 22 installation manual wiring connection. The Dynon HDX will drain doing it this way. The only other thing that could be wrong is the Dynon HDX that is allowing it to drain? Dynon did confirm the low voltage output of the Earth X fault is the cause.
Maybe I should ask and hope you don't mind sharing, are you connecting the Earth X fault to the Dynon HDX directly? Or as I described (to a LED)?
Thanks
Dan
Hi Greg
Sorry, maybe not clear. It is resolved in my plane now, the issue is the Earth X battery installed per the Earth X page 22 installation manual wiring connection. The Dynon HDX will drain doing it this way. The only other thing that could be wrong is the Dynon HDX that is allowing it to drain? Dynon did confirm the low voltage output of the Earth X fault is the cause.
Maybe I should ask and hope you don't mind sharing, are you connecting the Earth X fault to the Dynon HDX directly? Or as I described (to a LED)?
Thanks
Dan
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Hi Dan, I offer that this is indeed a curious issue.
I second what Greg says.
I have dual EarthX batteries, with dual HDX running my ship since 2 years, installed as per EarthX and Dynon.
I don't have the EarthX batteries connected to individual LEDs.
Never had a drained HDX back up battery, both show 100% charge and pass the yearly test.
Both are monitored by HDX through the EMS module.
I second what Greg says.
I have dual EarthX batteries, with dual HDX running my ship since 2 years, installed as per EarthX and Dynon.
I don't have the EarthX batteries connected to individual LEDs.
Never had a drained HDX back up battery, both show 100% charge and pass the yearly test.
Both are monitored by HDX through the EMS module.
I have the EarthX fault line wired into my EMS to give an indication on the screen, not using any separate LED's.
Yep, according to Dynon, they have no issues when connected directly to the HDX. I sorta understand why the 2V coming from the Earth X can cause the issue but do not understand why Dynon would not want to know more and work with Earth X to find a way to fix (prevent the issue of 2V in the system draining the B/U battery when the master is off). I do know how much of a hassle changing any kind of software but in the next software release, betting there are multiple things done at one time, one more might not be so bad....
In the meantime, I'll deal with it
Thanks
Dan
In the meantime, I'll deal with it
Thanks
Dan
