Is 4S enough for a medium lifter?

SchrodingersCar

SchrodingersCar

Member
I'll try to keep this concise, I've been strategizing for a while about trying to lift a panasonic LX100 with my F550. I'm about to pull the trigger on the Aimdroix extended arms, and some T-motor MN3110 700kv with 12" props. I'm considering the TP100 gimbal http://tppacks.com/store/index.php?route=product/product&path=60&product_id=56 but that's still up in the air. I'll fly dual 4S lipos.

The idea behind all this is to get the most bang for my buck just upgrading my current f550 setup. But the more and more I read it seems like everyone leans towards a 6s system for even a medium lift rig... But once I price out new batteries and then probably a bigger frame yadda yadda I always end up with something costing double.

I'd really like to start getting more professional quality shots. Will I be happy with my proposed setup? Or will it be lacking? I'd really like to avoid upgrading AGAIN in 6 months because this guy doesn't cut the mustard. Thoughts? Should I just start saving up for a tricked out s900?
 

DucktileMedia

DucktileMedia

Drone Enthusiast
It's more than enough, everyone did it with 4s for ages until the 6s thing became a fad. My advice, if you are buying everything now and dont already have a bunch of 4s components, would be to buy all 6s gear as it is more efficient. You will most likely wish you went 6s in the future if you go bigger heli. But I still have 4s on my helis and it has been fine, just not as long a duration flight time.
 

S

Silverburn

Member
6S is great - you can have endurance, or you can have power - it has a great spectrum. I use 6S for a 45 minute quad, and I use the same packs in my heavy lifter X8.

I only use 4S for my FPV performance machines now.
 

SchrodingersCar

SchrodingersCar

Member
If I DO go for a 6s system, what do people think about the DJI e600 system on an f550 extended to a 650 size hex? Or am I gonna wanna go with a brand new 800-900+ frame and get it over with? It's starting to feel like the real financial pain in this hobby can come from too many half-assed stepping stone upgrades...
 

R

Ronan

Member
I would go with a S900 + A2 and be done with it.

Get a nice 3 axis gimbal for a LX-100 and you got the high-end video covered.

Anything else and you will end up spending it on this kit one day or another.

Now if the budget doesn't allow it, then get w/e you can since it's better than nothing. Th E300/E600 is a nice bit of kit, a bit overpriced but the performance is there.

Would be a good setup for a small camera, F550 + Extensions + E600, but again, NOTHING compared to a S900 or similar.

Heck i use a $2000 gimbal (InfinityM) for my GH4 (very similar performance to the LX100 AFAIK) on my S900. You spend $$$ but cannot argue with the results!

So in conclusion if your budget is tight, i would concentrate spending money on a high-end gimbal and then see how much weight you need to lift.
 

P

PCMAerial

Member
Good question. I am in the same boat. Looking to put the Tmotor MT2814-400kv on a Y6. The spec sheet says compatible with 4s-8s Lipo. I plan to run two 4s in parallel, but I am just wondering if I'll be underpowered or not.
 

Bartman

Bartman

Welcome to MultiRotorForums.com!!
two 4S in parallel will be 4S and with 400 kv it will be very underpowered. two 4S in series though will be 8S and that would be fine so long as the weight is in line with the motors' performance and lifting capabilities on 8S.
 

P

PCMAerial

Member
Bartman said:
two 4S in parallel will be 4S and with 400 kv it will be very underpowered. two 4S in series though will be 8S and that would be fine so long as the weight is in line with the motors' performance and lifting capabilities on 8S.
Click to expand...

Thank you for chiming in Bart. I've been scouring for weeks and don't want to make the wrong buy. So you're saying 4s no matter if 10000mah is still underpowered for these motors, do you think 6s would do the trick?

In your opinion, would you run the 770kv on 4s or 400kv on 6? I don't see a giant difference in thrust, mostly just efficiency and amp draw between the two. Not looking for a crazy lifter or endurance rig. Just want to comfortably fly a Zen/Gopro for around 15min (ideally) and thus far my bench is centered around 4s LiPo's so that was the default choice

Thanks for the help!
 

Bartman

Bartman

Welcome to MultiRotorForums.com!!
the 770kv motors are awesome on 4S and with eight of them you can reliably lift up to about 14 pounds using 30C batteries and 40A ESC's. Temps above about 92 degrees F with high humidity will significantly affect performance/lifiting

400kv at 14.8 volts gives a theoretical max prop RPM of 14.8*400 which is 5920 RPM's which is too low to fly with. you might hover with that given weights and props but you'll likely be at max power to make it happen.

I really like the Tiger MT4008-18 on 6S packs for medium lift hell's.
 

P

PCMAerial

Member
Bartman said:
the 770kv motors are awesome on 4S and with eight of them you can reliably lift up to about 14 pounds using 30C batteries and 40A ESC's. Temps above about 92 degrees F with high humidity will significantly affect performance/lifiting

400kv at 14.8 volts gives a theoretical max prop RPM of 14.8*400 which is 5920 RPM's which is too low to fly with. you might hover with that given weights and props but you'll likely be at max power to make it happen.

I really like the Tiger MT4008-18 on 6S packs for medium lift hell's.
Click to expand...

Great! Really makes sense now. Looks like I may just stay with the 770kv. I currently have Tmotor 35a 600hz ESC's to pair. I think the 770 will carry the payload great. I'm just wondering if the efficiency will provide enough flight time with such a high rpm motor compared to the others. Thank you!!
 

Bartman

Bartman

Welcome to MultiRotorForums.com!!
the RPM's will be the same for a given prop and weight regardless of the voltage. the benefit of using higher cell-count, and therefore higher voltage, batteries is that for a given power output of the motor the higher voltage will result in lower amps which makes the motors/ESC's/batteries all run cooler and can make the flight times longer but that's a variable that depends on everything else to bear fruit.

i mostly went to 6S because there was too much of a difference in operating performance on very hot days vs. normal days to the point that I couldn't fly with what I had above about 92 degrees F.
 

Gary Seven

Gary Seven

Rocketman
Bartman said:
the RPM's will be the same for a given prop and weight regardless of the voltage. the benefit of using higher cell-count, and therefore higher voltage, batteries is that for a given power output of the motor the higher voltage will result in lower amps which makes the motors/ESC's/batteries all run cooler and can make the flight times longer but that's a variable that depends on everything else to bear fruit.

i mostly went to 6S because there was too much of a difference in operating performance on very hot days vs. normal days to the point that I couldn't fly with what I had above about 92 degrees F.
Click to expand...

That's an amazing and very useful tidbit of information, especially your last sentence. I guess density altitude is as big a ***** with MR's as it is with full blown aircraft.
 

P

PCMAerial

Member
Bartman said:
the RPM's will be the same for a given prop and weight regardless of the voltage. the benefit of using higher cell-count, and therefore higher voltage, batteries is that for a given power output of the motor the higher voltage will result in lower amps which makes the motors/ESC's/batteries all run cooler and can make the flight times longer but that's a variable that depends on everything else to bear fruit.

i mostly went to 6S because there was too much of a difference in operating performance on very hot days vs. normal days to the point that I couldn't fly with what I had above about 92 degrees F.
Click to expand...

Makes me wonder if I should just make the switch to 6s. But it looks like either way on 6s I'll have to swing a bigger prop. Ideally I'd like to stay around 11" or 12" because that is what most of my setup is built around. I see the 400kv motor recommends alot bigger propellers.

The MT2814-10 770KV seems like a reasonable motor. I can get them for a good deal, same price as the 400kv actually. But I do live on the coast which in the summer time it can get HOT out here. My eCalc already showed a motor temp of ~80F which to me seems high? I'm no expert, just thinking of an 80 degree motor spinning in 90+ heat puts up a red flag for me. Unless that is not so bad

I appreciate the help Bart, and also hope this information helps the OP and others who did not know this information. Hopefully I'll come to terms here soon enough lol
 

Bartman

Bartman

Welcome to MultiRotorForums.com!!

Bartman

Bartman

Welcome to MultiRotorForums.com!!
PCMAerial said:
Makes me wonder if I should just make the switch to 6s. But it looks like either way on 6s I'll have to swing a bigger prop. Ideally I'd like to stay around 11" or 12" because that is what most of my setup is built around. I see the 400kv motor recommends alot bigger propellers.

The MT2814-10 770KV seems like a reasonable motor. I can get them for a good deal, same price as the 400kv actually. But I do live on the coast which in the summer time it can get HOT out here. My eCalc already showed a motor temp of ~80F which to me seems high? I'm no expert, just thinking of an 80 degree motor spinning in 90+ heat puts up a red flag for me. Unless that is not so bad

I appreciate the help Bart, and also hope this information helps the OP and others who did not know this information. Hopefully I'll come to terms here soon enough lol
Click to expand...

i was able to manage the situation by flying a smaller lighter camera or just reverting to the kit lens that was much lighter than my wide angle zoom that i normally would have used. you have to look at your circumstances and see where you can make changes to keep flying when the temps and humidity start to go up. higher C rating batteries might have helped me as much as changing to 6S did but then I was also pushing the amp limits on my Mikrokopter BL2.0 speed controllers. I've been through a lot of evolutionary steps in the last four years, each one teaches a new lesson, it's just something you learn to accept as your needs evolve.
 


R

R_Lefebvre

Arducopter Developer
Guys, the "efficiency" benefit of 6S is completely over-rated. The difference is very, very small, assuming you are using two similar batteries of equivalent mass. ie: a 4S5000 vs. a 6S3300.

If you notice a significant difference, it's because something else changed.
 

Bartman

Bartman

Welcome to MultiRotorForums.com!!
R_Lefebvre said:
Guys, the "efficiency" benefit of 6S is completely over-rated. The difference is very, very small, assuming you are using two similar batteries of equivalent mass. ie: a 4S5000 vs. a 6S3300.

If you notice a significant difference, it's because something else changed.
Click to expand...

it's not about efficiency, a 25C 4S pack will do much worse for a given power load than a 25C 6S pack, it's about reducing amps and opening up the operating range of a heli for a given battery pack. i'd need 50C 4S packs at high temps where a 6S will coast through the whole range of temps. where 4S packs will make the voltage alarms chirp and blink throughout the flight the 6S packs will go almost to completion with stable voltage and cool temps.
 

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