Quad 18-30 amp esc's????

[wolfman76]

i will be using the fm-4008 fpvmanuals motor on my next quad Sam(breeze400) has told me i only need 18amp esc's... my question is has anyone heard of or used these esc's black mantis 20 amp esc's with built in bec...
Black Mantis 20amp esc speedcontroller
or does anyone else have any other suggestion on decent esc's for this quad i still have not decided wether it will be the qav500 or the team blacksheep quad both can be used for fpv... i was also looking at the castle creations thunderbird esc's also...

 

[Tasajara]

I am using 30A BlueSeries Brushless Speed Controller (USA Warehouse) on my QAV that I flashed with MultiWii code. I use 18-20 on 3s and 30 amp on 4s.
Just gives me a little head room on amp draw when doing 4s and would tend to run a little cooler.
Just my 2 cents

 

[Lee]

I have 20A flashed ESCs on mine. The limiting factor is the room between the frames, which is 11mm. Bigger ESCs have bigger Capacitors which tend to be too large to fit. Some people have removed the Caps from the bigger ESCs and replaced them with one big one soldered direct to the Circuit board frame.
Craig, would the 4S not have less Amps draw than the 3S? For the same configuration of course.

 

[Tasajara]

Yep higher Voltage with less amps will give you the same Wattage.. as lower voltage and higher current same wattage.

P (power)= V(voltage) x I(current)

500 watts = 14.8 v * 33.8 amps
as
500 watts = 12.6v * 39.7 amps

I do also have a setup with 20 amp esc's on 4s, but they are in open air. They tend to stay cooler.
My self I was not sure what all equipment I would end up with on my QAV, so as I said I went for the higher
rated esc. Just to have a cooler running system if I loaded it down with extra cameras and larger RX and battery.
20 amp would be fine if that is what you want to use.
I have also used these on my 4s Spider Quad.. SK-20A SimonK Firmware Multicopter Speed Controller ESC 20A
with this motor... Avroto 2814 Short Shaft