|Aug 10, 2012, 11:33 AM|
can't believe its been a month since i last posted now have a week off work so will be looking at making some progress.
Just in time, the Lipo pack arrived today so i can get the wiring done.
Question: can anyone confirm for me, the Lipo (Zippy 5000mah 4cell 30C) has 8AWG wire and my Y connector is using 14AWG, same as the ESC's (60Amp). Am i going to have problems using 14AWG? I'm thinking not as i don't think the ESC's would have used it if there would be problems but I'm wavering in my own judgement.
|Aug 10, 2012, 03:05 PM|
Yeah, your amps aren't high enough to be concerned. If you were 120+ amps, I'd be concerned with wire size differences and lengths. Smaller diameter and longer wires get hotter than larger diameter and shorter lengths. You'll be just fine.
You considering an HK Vixen when they come out
|Aug 11, 2012, 12:40 AM|
Yes i am or should it be will be . Got a few ideas that i want to try out that i couldn't do with this one. Any ideas on the release date yet?
|Aug 11, 2012, 08:26 PM|
The HK Vixen should be out in the next 3-4 weeks at the very most. The maiden has been do.e and apparently it flies very well. No turrets, but easy to add. It also has cheater holes like the Vampire. Yuck. LOL
|Aug 12, 2012, 01:53 AM|
D_Fast, thanks for the reminder. Hadn't forgot but as to make sure will do it now.
Sounds like they will be flying before me . With you on the cheater holes, they ruin the looks. Got a JP A4 Skyhawk and its peppered with them....not nice.
Think that's one of the possible mods i might look at
|Aug 13, 2012, 10:20 PM|
You can fill several of those holes on the Jepe A-4. It goes much better with them covered. There's a thread on here somewhere and it shows which ones to cover up.
|Aug 18, 2012, 06:05 AM|
Okay, another method chosen for sealing the EDF units to ducting: Using some foam tape overlaying the ends of the EDF tubes by approx 3mm and CAing into place I now have snug fit with no leaks. Ribbon is just wrapped under tubes to aid removal.
Started skinning underside, paper template made first then transferred to depron. I use the same template both sides to maintain symmetry. Exhaust pipes are wrapped in 3mm depron, three layers bringing them just proud of rear skin ready for sanding to shape later.
Wiring done as per diagram below, I’ve had problems with the controllers; can anyone tell me, should each controller be programmed together as per the diagram or each done separately. Currently when I start them up one fan begins and sometimes the second EDF starts but not always, when I does there doesn’t seem to be as much thrust from it not as much as first. Is it coincidental that the controller with red wire to receiver disconnected is the one not performing properly? Advice would be greatly appreciated.
In mean time I connected my meter/power analyser, at 40amps I was getting just over 610Amps.
|Aug 18, 2012, 06:58 AM|
Lookin' good Dom.
Program the ESCs separately. Checking each fan separately with the watt meter, noting the amp draw at ½, ¾ & ful throttle. The numbers off each fan don't need to be exact just somewhat close.
I have twin (P-38) and the motors seldom start up together. But by ½ throttle they're in sync. No problems.
The exhausts of the Vix are very close together. I doubt very seriously if you would ever notice any yawing from uneven thrust.
|Aug 18, 2012, 07:17 AM|
Boogie - thanks for the quick response, will do as directed and post results.
One last question, what would be the advisable set-up as per the attached instruction sheet? I.e. what throttle/brake setting.
|Aug 18, 2012, 08:56 AM|
Set Option 1 for what ever battery your using.
However I like to set the cell count/voltage cut off for a lower voltage than what I actually using.
I fly with a timer, working my way up from 2 min. flights, then 3 min., then 4+ min. over a period of weeks. Checking voltage after every flight. Maiden flight day are usually 2 min shakedown flights. Next flying session is bumped up to 3 min, etc.
When flying jets, I don't like the ESC suddenly taking over when it hits the low voltage threshold. Makes setting up for a landing dicey. You can get away with it on a prop job but EDFs are not know for their dead stick landings.
I know by my timer where my batts are at and have maximum power available until touch down. I may lose a battery but I won't lose a plane due to the ESC shutting down.
So far I haven't lost either.
Option 2: •• — 2 Short + 1 Long Auto Throttle Range *
Option 3: ••• — 3 Short + 1 Long No Brake
High revving EDFs stopping suddenly have been known to throw the rotor off.
Option 4: use default
Option 5: This is where you have some leeway. Low timing is less power and amps. But will more than likely be what you'll stick with.
Higher timing setting usually will only up the amp draw, make heat (wasted power) with very little to show for it. Only with some super-duper batteries and a rockem-sockem motor would advancing the timing really help.
But it's fun to play with.
Hook it up to a watt meter and see how the different setting affect you power system.
Option 6: use default unless you have some weird issue.
I've never had to mess with this setting.
|Aug 18, 2012, 10:25 AM|
After re-programming controllers per Boogies advice here are the results.
Amps Watts Amps Watts
1/2 throttle 14.34 220 15.02 229
3/4 throttle 28.5 430 31.2 442
full throttle 33.49 498 33.12 492
Controller temp, 56 deg 56 deg
Motor temp 53 deg 55 deg
1/2 throttle 23.15 345
3/4 throttle 49 701
Controller temp 62 deg
Motor temp 69 deg
Didn't go as far as full throttle with both motors as at 3/4 throttle fuselage nearly leapt off its mount. Also didn't want to push ESC's without cooling as the temp increased significantly.
Well I'm pleased with the results, thanks again Boogie for your help.
Would i be correct in assuming that with both motors running the readings are cumulative i.e. 24 Amps and 350 Watts each... or am i assuming too much?
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