battery information display

[John Kerr(Guest)]

In use the battery information appears unbidden in the lower left. It shows a M=some value less than a/c power volt meter. Suggestions in understanding/troubleshooting?

John Kerr, 21 hours on RV 9, N927BJ

 

[dynonsupport]

It may be the unit, but note that measuring voltages at different places in your electrical system CAN produce different results. What are the voltage values at the dedicated meter and the EFIS? Also, you might try measuring the power with a volt meter at the EFIS connector to determine that the voltage that the EFIS is reporting is accurate or not.

 

[John Kerr(Guest)]

the a/c power volt meter is showing 14v (nominal) for 13.8v

the M reading on the EFIS fluctuates between 12.5v and 13.5v continuously. The unit voltage is steady at 16.(?). I can hide the voltage display with the info button but it will reappear shortly thereafter.

John Kerr

 

[dynonsupport]

When you say "unit voltage" I think you are refering to the "I" item on the voltage display. This is the voltage of the internal battery if you have it. Over 16V is basically a full charge. This indicates a perfectly normal battery state.

Do you have the ability to put a voltmeter up to the pins at the back of the EFIS to measure the voltage at the back of the EFIS? Alternatively, can you hook the EFIS up to a stable, known power supply outside of the aircraft? What we're looking for is proof that the EFIS is wrong, or confirmation that the power is actually fluctuating at the EFIS.

As always, we'd be happy to have the unit back for testing here if you would like. If you'd like to do this please call us at 425-402-0553 to set up a return authorization.

 

[John Kerr(Guest)]

I will continue to monitor this with other indications, such as the inability to calibrate the EDC that I have discussed with JR. I am still in the primary test phase and therefore do not have more than about 30 minutes of sustained power. I will stay in touch.

John Kerr

 

[John Kerr(Guest)]

I took the opportunity while doing a 25hr inspection to check power and ground connections to the Dynon. Main power was fine, BUT the small ground buss the Dynon was grounded to was snug not TIGHT. Putting a wrench on the bolt not only eliminated the voltage fluctuations on the Dynon but eliminated a rpm sensitive buzz on the am/fm.

It seems that checking ground connections is something that must be learned more than once.

JR., I am waiting good weather to get back to the compass rose and see if the EMC calibration problems are similarly solved. Is it possible that the irratic "counting" during calibration could be the result of voltage/ground fluctuations?

Thanks for your help