How do I properly understand & configure my voltage settings in the A2?

[gottabebrett]

I just hooked up my S1000 and Zenmuse w/Canon 5D mkiii and am getting voltage warnings way too early (I believe). I am struggling to get a grasp on these battery settings in the A2 (and WKM back when I was flying my S800 EVO). I have the first (yellow) alarm set for 22.0V and the second (red) alarm set for 21.0V. I lift off with one fully charged 6S MaxAmp 10900mAh (about 25.19V, balanced, confirmed with Hyperion checker). Around the 3:00 mark, I start getting the yellow warning light. That yellow warning last all the way to about the 9:00 mark, and as soon as I see the red light blink I land immediately and check the voltage: 22.51V. Why are these alarms going off so early? Why am I getting a red LED at 22.51 when it's configured not to trigger until 21.0? I have no idea what the LOAD settings mean, so I am wondering if that has something to do with it. Also, the temp today is about 39F, with an 11 mph wind (pretty cold, don't know if this has something to do with any of this). You look what you know what you are doing, so any help would be greatly appreciated! I have a grand canyon trip early April so I am trying to get everything buttoned up before. Thanks - Brett from Plymouth, MI.

 

[rilot]

The LOAD settings are the voltage drop when in flight. When your MR is drawing power, the voltage of the battery will drop a fair bit thus triggering your limits. The LOAD is the difference between your flying voltage and your resting voltage.

Best way to calculate is to set your first level at 2V below your measured voltage before flying.
Fly until you get the warning then land immediately.
Check the new rest voltage of your battery.
The difference is your load or drop. Enter this figure in to the appropriate box then go back and set your actual warning values to what you had (or maybe slightly higher)
Keep flying and testing and making note of how many mAh you are putting back in to your batteries, and changing the voltages until you get to around 80% used.

Bare in mind that new batteries will have a bigger drop until they are broken in so do the calculation again after 10 or 20 flights.

 

[gottabebrett]

The LOAD settings are the voltage drop when in flight. When your MR is drawing power, the voltage of the battery will drop a fair bit thus triggering your limits. The LOAD is the difference between your flying voltage and your resting voltage.

Best way to calculate is to set your first level at 2V below your measured voltage before flying.
Fly until you get the warning then land immediately.
Check the new rest voltage of your battery.
The difference is your load or drop. Enter this figure in to the appropriate box then go back and set your actual warning values to what you had (or maybe slightly higher)
Keep flying and testing and making note of how many mAh you are putting back in to your batteries, and changing the voltages until you get to around 80% used.

Bare in mind that new batteries will have a bigger drop until they are broken in so do the calculation again after 10 or 20 flights.

Thanks, Rilot. I can't wait to wake up and try your suggestion, as you can probably tell I am kind of new to this stuff. I see in your footnotes that you also are using the A2 with 2.4 ghz datalink, which CAN do you have the air end plugged in to? The A2 manual says to go with a CAN 2, so I used the only remaining port: the "non-clippable" port on the A2's PMU. I am assuming this port is the same as the rest of the CAN ports, just uses a slightly different connector. Anyway, I am trying to use my iPad to run the simulator (while indoors) and keep getting wild iPad errors (disconnecting, pop-ups galore about modes switching to GO HOME and LANDING and such). I can't get the flight simulator mode to function, and I don't know if this is a result of me being indoors or using the wrong CAN port, but I certainly don't want to try anything live until I get the simulator working first! Tomorrow morning I was thinking about trying a CAN BUS so that I can try a different (previously occupied) port. I also don't know much about interference, but I didn't know if it is playing a role here. I am using the A2 (2.4ghz) controller, Futaba 2.4ghz for my gimbal, and 5.8ghz for DJI video downlink -- could this be making it act up?

Any suggestions on what I could be doing wrong?

 

[rilot]

I've not tried the iPad GS yet. I use the PC one.
I have my A2 connected as per the diagram in the A2 manual. I can't remember which port it's in and I'm away from home at the moment without access to my ops manual.

 

[Tahoe Ed]

Thanks, Rilot. I can't wait to wake up and try your suggestion, as you can probably tell I am kind of new to this stuff. I see in your footnotes that you also are using the A2 with 2.4 ghz datalink, which CAN do you have the air end plugged in to? The A2 manual says to go with a CAN 2, so I used the only remaining port: the "non-clippable" port on the A2's PMU. I am assuming this port is the same as the rest of the CAN ports, just uses a slightly different connector. Anyway, I am trying to use my iPad to run the simulator (while indoors) and keep getting wild iPad errors (disconnecting, pop-ups galore about modes switching to GO HOME and LANDING and such). I can't get the flight simulator mode to function, and I don't know if this is a result of me being indoors or using the wrong CAN port, but I certainly don't want to try anything live until I get the simulator working first! Tomorrow morning I was thinking about trying a CAN BUS so that I can try a different (previously occupied) port. I also don't know much about interference, but I didn't know if it is playing a role here. I am using the A2 (2.4ghz) controller, Futaba 2.4ghz for my gimbal, and 5.8ghz for DJI video downlink -- could this be making it act up?

Any suggestions on what I could be doing wrong?

If you are using iOS 7.xx there is an issue with the sim mode. It works with 6.xx. All the other functions work.

 

[gottabebrett]

If you are using iOS 7.xx there is an issue with the sim mode. It works with 6.xx. All the other functions work.

Thanks, Tahoe Ed. So are you saying that in iOS 7.xx everything should work fine with the only exception being simulator mode? In other words, do you think it is reliable enough for me to use with my $10K S1000,A2, and Canon 5D Zenmuse?! Haha. I'm thinking maybe I will take off the camera and gimbal (replace it with a counterweight) and give it a whirl without sim mode -- or do you think that is crazy? I checked out the ground station software for the PC and it seemed a little bit intimidating at first glance --- the iPad software just looks so so so simple and straightforward.

 

[Tahoe Ed]

I would recommend getting used to the GS control on something less expensive than a $10,000 AP ship. Have your Tx handy so you can take control in case something happens. You just need to switch out of GPS to regain control.