Two MAXAPMS 11000mah in parallel?

[saidquad]

Current Setup:
S800 frame+WKM+ VTX (immersionrc 600mw)+Z15+Nex7 (incl. pancake Lens )+ 1 maxamps 6s 11000mah =>Total weight: 6180g
Using above setup and maxamps 95% charged before takeoff and landing the bird when total remaining voltage is 22.2V onload (thus 3.7 per cell) => 8 minutes of flight time
I’m thinking if it would be efficient to fly with two 11000mah maxamps in parallel (again 95% charged before flight and land on 22.2V onload). Adding another maxamps would increase the total weight to 7400g which is 400g above manual instruction. Is it good?

 

[flyingbiscuit]

Current Setup:
S800 frame+WKM+ VTX (immersionrc 600mw)+Z15+Nex7 (incl. pancake Lens )+ 1 maxamps 6s 11000mah =>Total weight: 6180g
Using above setup and maxamps 95% charged before takeoff and landing the bird when total remaining voltage is 22.2V onload (thus 3.7 per cell) => 8 minutes of flight time
I’m thinking if it would be efficient to fly with two 11000mah maxamps in parallel (again 95% charged before flight and land on 22.2V onload). Adding another maxamps would increase the total weight to 7400g which is 400g above manual instruction. Is it good?

MAXAMPS 11000 ARE APPARENTLY JUST 5C :upset:!! THE 40C IS BURST

 

[vislaw]

MAXAMPS 11000 ARE APPARENTLY JUST 5C :upset:!! THE 40C IS BURST

You can find discussions regarding the MaxAmps rating. Apparently others find them not suitable for heavy lift Cinestars but they are the best option for the S800 (provided you are willing to pay the premium price). Their mah per weight ratio hasn't been equalled to my knowledge and for professionals able to charge clients for the work, the MaxAmps will give you the most flight time.

I'd hesitate flying so much expensive gear with a setup that puts me 400g above the rated weight limit of the s800.

I'm also curious why you charge only to 95%. My chargers all deliver full charge and I've not heard a claimed advantage to setting it to put less than 100% in the battery the day before I fly.

 

[saidquad]

I am very disappointed to hear that constant c rating of my maxamps lipos are actually 5c. This information was not clear on the website of the maxamps (at least I didn’t realize). But anyway, I am glad to hear that maxamps 11000mah is still the best choice (regardless the price) for s800 since I use them only for s800. I charge lipos to 95% capacity because I have experienced that charging from 95% to 100% takes long time and has little effect on flight time. Back to my question, it seems that not so many choose to fly an overweight S800. Especially when I am thinking to replace the standard landing gear with the retractable landing gear which (if I am correct) is 450g heavier than the standard landing gear. That means the total weight of my s800 would be 6630g with one maxamp lipo and 7850 using two maxamps in parallel. But I would like to have longer flying time. Any more suggestions?

 

[flyingbiscuit]

I agree if it's true, and from what I have read it is, I am no longer going to deal with maxamps, they are not a company that I would trust or do business with again
http://www.rcgroups.com/forums/showthread.php?t=1761789 (hope it's ok to link to another forum)

 

[DennyR]

View attachment 8179This is by far the most effective cameraship that I have built and it uses two 11000 maxamps in series FWIW.
View attachment 8181 I think for a S800 and two 11 amp batteries you would need 15x4.5 props. or even 16" with the tips cut back slightly. The question is Do you really need more endurance, most jobs can be achieved with 15 mins flight time and less stress on everything.

 

[saidquad]

I was thinking to connect them in parallel to increase mah. I get only 8 minutes flight time with one maxamp (discharging to 3.7 per cell). I need at least 15 minutes flight time. As mentioned I do not know if the extra weight of the second maxamps would kill the extra mah it brings. Also what possibly could happen to a 850g overweight s800?

 

[DennyR]

I was seeing 7-8 mins with a 5 amp battery on a S800. something else is wrong. Are your temps high?

 

[saidquad]

Motors and esc’s are cool after landing. The only thing could be my habit of charging and discharging lipos. I charge them 95% and land 3.7v per cell (onload). After landing it is 3.8 per cell. I don’t know if this habit has so much effect on flight time. Did you have full load around 6200g on your s800 with 5ams lipo? If it is so I definitely have to recheck everything once again.

 

[mitmit]

Total weight: 6180g
Using above setup and maxamps 95% charged before takeoff and landing the bird when total remaining voltage is 22.2V onload (thus 3.7 per cell) => 8 minutes of flight time
I’m thinking if it would be efficient to fly with two 11000mah maxamps in parallel (again 95% charged before flight and land on 22.2V onload). Adding another maxamps would increase the total weight to 7400g which is 400g above manual instruction. Is it good?

ask digitech. he is magician on the subject of efficiency)