(13-03-2012, 09:33 PM)secant0give Wrote: If you were drawing 90A continious I would also say way too much!!
But that is flat out and static, ie tied to a post.
Once it gets in the air it will be unload and the current draw will fall off a bit
The ESC he's using is rated at 85 A continuous and 100 for 10 second burst so it should be OK
The motor is rated for about 80A as well
here's a link https://www.leaderhobby.com/product.asp?...4001100041
The Lipo's are 20-30C 3000mah so can handel 90A for the odd 10 second burst
you can go a long way in 10 seconds!!
The trick is to use the throttle judiciously treat it like nitros and only use max throttle in short bursts of about 4-5 seconds. That's all you need any way.
This way you get the most out of your power system and the ultimate in power to weight.
you just cant use it 100% of the time but you don't need too?? It will have heaps of grunt about 2000W peek (90A) power for short bursts and 1000-1500 (45A-60A) to put around with in between those bursts, that will be fairly sprightly putting around too I might add.
If you go vertical on full noise for 6 seconds you'll be at cloud base on a clear day for sure (read 399.99ft)
ok TODAY was a trial test day , lots of hours spent static testing . if any one finds this boring dont read , but i had a ball .
what i found was this !!!!
. THERE ARE 6 WHITE LINES in the throttle stick , the 3rd being 1/2 way ,50%
so i took readings from line 3 ( 50%)
line 4 ( 67%)
line 5 (83% )
line 6 (100%)
IT HAS AN 85 AMP ESC IN IT , WITH 100 AMP 10 SEC BURST , AND AN 80 AMP 700KV 5055 MOTOR , USING 6S 3000mah 20C battery pack .
OK. WHAT HAVE I FOUND .
THE PROPS FITTED ALL PULL HIGH RPM, NO noticable difference in rpm with any prop. the 12x10 APC WAS A PURE SCARE !!!!
IT PULLED 40 amps @ 50%
70 amps @ line 4
130 amps @ line 5. i didnt bother with line 6 .
then there was a lightwood 13x6 , APC 13x6.5 and APC 12x8.
these were all pretty much even in thrust and amps throughout the rev range , with the lowest draw from the 13x6.5 APC .
IT PULLED 28 amps @ 50%
48 amps @ line 4
79 amps @ line 5
96 amps @ line 6 all continual , all static . 10 second bursts .
my thoughts are that line 4 is pretty is pretty hard flying and would be going upwards vertically . 50% line 3 would see a close hover .
i conclude in theory guesstimate that flying around at line 4 would be a hoot and it would be pulling about 25 amps at that in the air .
the ESC FREQUENCY IS SET at 8 khz factory default , and the timing is automatic from 7 - 30 degrees . the thermo soft reduction cuts in at 110 degrees which cuts power to about 30% .
on a static test at 50% throttle constant 28 amps after 4 min 30 secs . it started dropping off current even though still at 23 volts . after a 5 minute cool down it did another 5 minutes , and still had each cell at 3.7volts .
so i'm hoping in the air with air speed and unloaded prop we'll have better cooling and a lot less current draw than static , which means hopefully after quite a few test flights , it can hoot around for a good 4 minutes.
time will tell . hope this is interesting . i certainly enjoyed the day .
OMG if only technology was available for it to drive that 12x10 , or 13x8 prop at those revs .
saing that i just hope it can drive the 13x6.5 or 12x8 with the grunt it has .
seems to be abig difference between a 700kv , and 580kv and 470kv
setup [/align]