Since it is imperative when planning auto missions to know your flight times I have been testing with stabilize/loiter hovers and measuring air time while I familiarize myself with the Arducopter platform.
I now have 17 full flights with respect to battery failsafe at 10.5 volts. I bought 3 batteries with the IRIS.
On these batteries the best hover time I can get is 10.5 to 11 minutes.
Yesterday I bought a more expensive Thunder Power RC G6 Pro Performance 3850mah 45C battery and a HI-Tech X1 MF balance charger. On the first flight with that battery I got 13 minutes hover/loiter. I hope to try it again today. Maybe it will get better after a couple of cycles. I only charged it with 1.9 amps for the first charge.
BTW - The $74 I spent on the charger was worth it. It charges the IRIS 3500 packs in an hour at 2 amps(well below 1C). The stock charger was taking 2.5 hours. it also displays the individual cell voltages and has a storage charge feature.
All battery tests were done with no payload. No legs, no camera, just like it comes out of the box.
I am curious to know what others are getting. The IRIS was advertised 10 to 15 minutes flight time. Assuming that it means 15 minutes with no payload and 10 minutes with legs and gimbal I would obviously like to be at 15 minutes with no payload. Doesn't seem possible as delivered.
You set the battery failsafe under "Initial Settings/Mandatory Hardware/Failsafe while the Pixhawk is connected to your computer. You don't have to have the battery in the copter.
You can set the battery failsafe voltage and whatever mode you want it to be in when the failsafe kicks in.
You can then turn on the battery warning verbal message from the GCS by going to "Config/Tuning/Planner" When you check the battery warning box it will ask you to enter the voltage and pcnt that you want the warning. I set the warning at 10.7 and the failsafe at 10.6. I set the percentage warning and failsafe at zero. I only care about the voltage. I uses different sized packs a lot and I don't want to have to change the setting every flight. In addition, the percentage levels are strictly non-empirical calculations. The voltage level is a directly measured value.
You don't really need to track mah values while flying anyway. you just want it on the ground before the voltage gets too low.
hope this helps
Loiter hover with FS at 10.6
Not bad for the cost.
I was only getting 15 minutes before but I had repaired a black arm and that motor was cocked a little off angle. I also had a lot of gorilla tape and CA on the repaired arm. That motor was also failing.
I replace the arm and the motor which decreased the hover current by almost a full amp
Still wanna try the A-SPEC 4500
With the stock batteries in your config I'm getting about 10 minutes (now that I can fly well enough to be aloft that long) and got about the same as you with the zippy 5000 (16 minutes). Yes the zippy is a good deal!
Wanted to let everyone know about another good battery. I've been looking all over the place for a good high capacity battery that doesn't weight a lot (and doesn't cost as much as Thunder Power batteries). Finally found one. I bought one, tested it and just bought 2 more today. First flight with it, I got 16 minutes 15 seconds until failsafe kicked in at 10.5V (no payload). I only assume it will get slightly better as I put more cycles on it. It's a 4600mAH 3S Dualsky battery (their HED series), only weighs 300g, and easily fits the battery compartment. However, it doesn't come with a battery connector so you will need to solder one on yourself. I've also tested it on my Phantom with Tarot gimbal, GoPro, and 200mW vtx and got 14 min of flight time. Hard to find them but there's a guy on ebay (atomikrc) selling them for $37 and some change.
The battery won't fit in the Phantom 1 shell. I bought the Phantom 2 shell in order to take advantage of the larger battery compartment and moved everything over to it (all electronics with the exception of the LED/USB board are a direct swap over). With the larger battery compartment you have lots of options. You can fit 2 stock phantom batteries in parallel or I've even used a Traxxas 5000maH battery that I have laying around for my trucks. I have access to a commercial 3D printer at work so I've also printed a custom quick connect adapter for the gimbal and some custom feet that snap into the groove on the legs of the Phantom to raise it up a little.
I also was not satisfied with 10 minute flight times so I did some digging and found out that there are some 5,000MAH batteries that fit nice and snug in the battery bay.
I bought 2 5,000 MAH Vortex batteries off Ebay, I'm charging them right now on a duel port charger I also purchased on Ebay. BTW I'm flying with a gimbal, gopro3 and extended legs.
Im going to fly, not just hover, until the quad goes into 'Land' mode.
I'll post my flight times when I'm done.
Not to pry, but did you ever get results with those 5000mah votex batteries? I'd really like to know those real flying times with gimbal.
Just my two cents, I seem to be having slightly better results with my stock batteries. With no payload, I am consistently getting 12.5 minutes of flight time manually hovering in Stabilize, set at 10.7 volt threshold. The only other mod I've made to stock IRIS other than adjusting that failsafe is balancing the props, which were pretty good to begin with.
I timed my first battery test with the gimbal/GoPro payload this AM and was surprised to get 7:31 out of it in Stabilize/hover, which is a good minute longer than most others. Don't have an explanation. I'm still putting in the Zippy 4000, but I feel like my flight times are adequate for the missions I need to fly.
Are you using the stock 10x4.7 propellers? Also are your motors getting hot?
I would like to know what is so different between his Iris and ours. With the full stock payload(legs, gimbal camera) and the ZIPPY 5000 I don't have enough power below 11 volts to maintain altitude. My motors get extremely hot. I have even change out every motor. 120 to 145 degF as measured with a temp gun. I already gave up though. Stripped it down and will be building a new machine from scratch.