G'day All,
This is my first post to the forum and I am hoping someone can tell me what is going on. I am responsible for a fleet of three H520's that are primarily being tasked with 3D mapping duties. After having to replace a significant number of LiHV batteries I started to become a bit more vigilant on the performance of individual batteries.
What this has revealed is significant differences between what the ST16 controller is indicating is left in a battery and what the SkyRC charger is reading. Landing a battery at around 30% shows the batteries at pretty close to 15.0V on the ST16. Getting them back to base for charging approximately 45 minutes to an hour later will have the ST16 showing the same battery at 41% and 15.1-15.3V. Upon plugging the battery into the SkyRC charger immediately after cming out of the aircraft I am getting the indication the batteries are only at 9-12% and pretty much the same as the landed voltage readings from the ST16. This seems a large discrepancy between the two. I had noted that a LiHV battery charged to 80% reads at 100% in the ST16.
My main concern is that a battery landed at 30% on the ST16 is only at 9% according to the SkyRC charger. If it is flown to below the 30% mark what may be the implications? If the SkyRC is the right reading could I see a situation of an aircraft dropping out of the sky because it hasn't read its charge state correctly? Is it possible that Yuneec has not adapted its system to accurately read the true state of the LiHV batteries as opposed to a standard LiPO? Is my SkyRC unit the issue? To allow a safety margin I have mandated the batteries not be flown under 40% until further notice. I would like to think that a pilot can trust what they are being told by the battery in the aircraft at the time and not having to guess/compensate. I am not going to make any claims as to being a battery expert and therefore the observed discrepancies have me concerned enough to consult the brains trust. It may something very simple that I haven't picked up on. I hope that is so!!
Cheers
This is my first post to the forum and I am hoping someone can tell me what is going on. I am responsible for a fleet of three H520's that are primarily being tasked with 3D mapping duties. After having to replace a significant number of LiHV batteries I started to become a bit more vigilant on the performance of individual batteries.
What this has revealed is significant differences between what the ST16 controller is indicating is left in a battery and what the SkyRC charger is reading. Landing a battery at around 30% shows the batteries at pretty close to 15.0V on the ST16. Getting them back to base for charging approximately 45 minutes to an hour later will have the ST16 showing the same battery at 41% and 15.1-15.3V. Upon plugging the battery into the SkyRC charger immediately after cming out of the aircraft I am getting the indication the batteries are only at 9-12% and pretty much the same as the landed voltage readings from the ST16. This seems a large discrepancy between the two. I had noted that a LiHV battery charged to 80% reads at 100% in the ST16.
My main concern is that a battery landed at 30% on the ST16 is only at 9% according to the SkyRC charger. If it is flown to below the 30% mark what may be the implications? If the SkyRC is the right reading could I see a situation of an aircraft dropping out of the sky because it hasn't read its charge state correctly? Is it possible that Yuneec has not adapted its system to accurately read the true state of the LiHV batteries as opposed to a standard LiPO? Is my SkyRC unit the issue? To allow a safety margin I have mandated the batteries not be flown under 40% until further notice. I would like to think that a pilot can trust what they are being told by the battery in the aircraft at the time and not having to guess/compensate. I am not going to make any claims as to being a battery expert and therefore the observed discrepancies have me concerned enough to consult the brains trust. It may something very simple that I haven't picked up on. I hope that is so!!
Cheers
