View Full Version : Discussion 33% Cap232 & Hacker A80-10 / Spin Box max current readings?
Tipover
Jun 17, 2009, 11:50 PM
I'm new to this size electric and sort of scratching my head in confusion.
I'm flying my Hanger 9 33% Cap232 with a Hacker A80-10, Spin 170, 12s1p 5000ma 30C Zippy packs, and an Xoar 26 x 12e.
Spin box says 83A max and the voltage is pulling down to 41.5v. I'm doing a full throttle climb from takeoff for 4 seconds to assure an accurate current reading.
Seems strange that I would only be pulling 3400 watts with this prop/motor combination, and the batteries are coming down pleanty warm, in fact one set slightly puffed tonight after some aggressive pattern flying. I previously had been running a Xoar 25 x 12e and only getting 70A max with voltage around 44v.
I suppose I need to get an inline current meter and get to the bottom of this situation. I've read someplace that the spin box does not read anything over 100 amps, but rather starts over at the 100A point. No way I can be pulling 185 amps and 8000 watts with these batteries, correct? :eek:
Anyone have any real world current meter readings using these props and motor combination? Any insight greatly appreciated.
Kevin
edible_engine
Jun 18, 2009, 05:12 AM
add a 1 onto the front, it never adds the leading digit for some reason
my A200 only drew about 20 amps.....
Tipover
Jun 18, 2009, 10:30 AM
add a 1 onto the front, it never adds the leading digit for some reason
my A200 only drew about 20 amps.....
I had considered that. I'm simply having trouble believing that the 12s1p Zippys are capable of that much power.
I guess a clamp-on dc amp meter is next in order. I really do not enjoy running these big motors up on the ground though.
To bad Hacker/Jeti can not get the current reading thing staightened out. At least mentioning it in the instruction manual would be of some help. The guys at Hacker Aero don't seem to have a clue about it either.
Kevin
dag214
Jun 18, 2009, 11:10 AM
I had considered that. I'm simply having trouble believing that the 12s1p Zippys are capable of that much power.
I guess a clamp-on dc amp meter is next in order. I really do not enjoy running these big motors up on the ground though.
To bad Hacker/Jeti can not get the current reading thing staightened out. At least mentioning it in the instruction manual would be of some help. The guys at Hacker Aero don't seem to have a clue about it either.
Kevin
Not sure if any of this will help, but... my hacker/Jeti spin set-up gives me good reading, but at first it did not as I had the ESC set for the wrong poles and wrong motor, once I set it right, the ESC gave me spot on right info.
Give Mike Donovan at Hacker a call, he seems to be the go to guy, and has always gotten me the correct info, and fast.
Good luck,
DAG
Tipover
Jun 18, 2009, 12:43 PM
Thanks, Dag
I put a call into Mike, waiting for a callback.
I have pole count set to 20, 22 degree's timing, 8khz as per A80-10 specs. Should be correct.
Readings look correct except for Max current. If I really pulled 183A, that would explain everything. Still Skeptical of that much power though. Plane has pleanty power for sure, I just wanted to get it up in the 5000 watt range. That is why I swithced from the 25 x12 to 26 x12 :)
BTW, your B-36 project is really great. I've been watching, just not worthy of getting in the discusion.
Kevin
dag214
Jun 18, 2009, 01:58 PM
Thanks, Dag
I put a call into Mike, waiting for a callback.
I have pole count set to 20, 22 degree's timing, 8khz as per A80-10 specs. Should be correct.
Readings look correct except for Max current. If I really pulled 183A, that would explain everything. Still Skeptical of that much power though. Plane has pleanty power for sure, I just wanted to get it up in the 5000 watt range. That is why I swithced from the 25 x12 to 26 x12 :)
BTW, your B-36 project is really great. I've been watching, just not worthy of getting in the discusion.
Kevin
Kevin,
I know this sounds crazy, but I jumped into electrics with both feet with park fliers, then moved to my B-36 project, what a jump. I know very little to nothing about electrics. All I do know is that when I think it is the equipments fault, it is mine. Mike at Hacker is great, tell him DAG said that he will make everything perfect for you. And anyone is worthy of saying anything on my B-36 thread, as long as it is not about stuff that has nothing to do with cool aviation stuff.
Thanks, DAG
edible_engine
Jun 18, 2009, 03:06 PM
also, an important thing, the Jeti is very inaccurate with current draw unless it reads 4 seconds of maximum power. Even then its only 10% accurate. if you just give it a blip on the ground you will get some really weird numbers
Tipover
Jun 18, 2009, 04:30 PM
I talked to Mike.
He said the spin box likes to see 15 seconds of full power for an accurate max current reading. I don't quite understand the measurement process, but the FET's temps are data logged and the current is calculated based on average temps I guess. So a fast current spike won't heat the FET's up for an accurate enough reading.
Even so, Mike was suspect of my current readings. Based on my max voltage readings he suspects my Zippy 4mm bullet connectors are dropping to much voltage, thus giving lower than normal max current readings. The 4mm bullets that come on the 30C Zippy packs have the little spring contacts that do not fit real tight. Nice to plug and disconnect, but not so good with high current applications. He suggested Deans Ultra or machined 6mm bullets for anything up around 100 amps.
Bottom line is that a 1p setup needs very good low resistance connections to efficiently pull the high current needed by these bigger motors. Also likly is that the spin box is not picking up on actual high current spikes, only long averages.
Not looking forward to changing all those bullet connectors.
Kevin
edible_engine
Jun 18, 2009, 05:07 PM
deans on 100A, you must be having a laugh!!!!
get some 5.5mm gold connectors minimum, CC6.5 are a little better and for the best, plettenberg 6mm golds!!
Deans are a no no for me above 60 or 70 A
(start the war :D )
Tipover
Jun 18, 2009, 10:21 PM
Deans are very handy connectors. I personally don't see them as having a very large surface contact area. I do understand a lot of guys are using them on 12s setups. I wonder how their contact resistance compares to 6mm machined bullets?
Are these what you guys are using for 6mm bullets? I'm assuming these are what are referred to as machined connectors?
http://www.rctoys.com/rc-toys-and-parts/DF-BULLET-60MM-3M3F/RC-PARTS-CONNECTORS-WIRING.html
Kevin
Jeffery
Jun 18, 2009, 10:54 PM
I use the 6mm bullets from Neu, like $24 for 10 pairs shipped. They look like this
blucor basher
Jun 18, 2009, 11:11 PM
(start the war )
No one cares about a war. I'll just keep using Dean's on my 100A setups. If they ever get hot, I'll let you know.
Jocke
Jun 19, 2009, 05:14 AM
Change the deans to some god 5 och 6mm golds, you will have loses in the Deans! they are "ok" up to about 50Amps, 4mm gold 80Amp, 6mm pletti 150Amp+ and they last very very long.... good qualety.
As already said, the SPIN messures avg max Amp based on the IR in the fets, and if the motor/ esch have any kind of problem, like wrong settings so it will lose sync the readings will be wrong, try and do a static test with full power for 5sec and see the data, then use a clamp amp to confirm.
Magne
Jun 19, 2009, 05:37 AM
Kevin.
On Hackers website they have an example showing the A80-10 with 12s (42V) spinning a 24x12 Mejzlik at 6150 rpm and pulling 4620W.
Assuming you get about 6000 rpm with the 26x12, the power would be approx. 5600-6000W. (Estimate!)
At 41,5V this is equivalent to 135-145A.
What sort of flight times are you getting with your set-up?
Magne
Tipover
Jun 19, 2009, 12:03 PM
Kevin.
On Hackers website they have an example showing the A80-10 with 12s (42V) spinning a 24x12 Mejzlik at 6150 rpm and pulling 4620W.
Assuming you get about 6000 rpm with the 26x12, the power would be approx. 5600-6000W. (Estimate!)
At 41,5V this is equivalent to 135-145A.
What sort of flight times are you getting with your set-up?
Magne
Magne, Interesting point you bring up.
My spin box max rpm readings are generaly 6300-6500 rpm's except for that one high spirited flight. Not sure why Mike was alarmed with my 41.5V reading, not that far down from 42V.
I have my flight timer set to 7 minutes, I try to be landed by that time. On the average been putting back in 3500-4000ma. On the meltdown flight I had a max rpm of 6740. Turns out I over discharged my batteries on that flight...could not even taxi back. I put back something over 4900 in the packs :eek: Those two packs balance charged fine, I flew them last night with no issues. The slight puffing seems to have gone back down.
The larger plane covers a lot of ground and it’s easy to stay on the throttle to long. Slight learning curve ;)
Here are my spin box readings from that one harsh flight.
Max Temp 38C
Min Temp 18C
Max Current 83.0A 41.55V 5:18
Min Currrent 52.1A 37.47V 6:25
Max Volt 50.78V
Min Volt 28.05V
Off Volt 28.56V
Motor Run 6:37
Power On 7:31
Motor Pole 20
Max RPM 6,740
Kevin
Tipover
Jun 19, 2009, 12:10 PM
(start the war )
No one cares about a war. I'll just keep using Dean's on my 100A setups. If they ever get hot, I'll let you know.
For what its worth my 4mm bullet connectors are not even warm after a flight.
Kevin
Tipover
Jun 19, 2009, 11:25 PM
Tonight I found out that my Hyperion e-meter would read above 100 amps in the peak hold mode. Otherwise it will blank with anything over 100A.
With a couple fresh charged packs I got 115A max and min voltage held at 42v. Pretty close to 5000 watts. Of course I had to add a couple Deans and 2 more 4mm bullets connectors to hook it all up.
Here are a few pics of my electric conversion in case anyone is interested. I don't recall ever having seen this plane converted to electric. Was pretty straight forward, I only used the two outside aileron servo's and one on rudder. All servo's are Hitec 7955's. All up weight is just under 23 lbs. Mounted my wood motor spacers to the tee nuts for the Zenoah GT80. If I get sick of the electric version I can easily convert it to gas :rolleyes:
Kevin
bsipro
Jun 23, 2009, 01:37 PM
Hey Tipover
nice setup I have been using the A80-8 in my 33% sukhio and 260
Im very happy with the performance I use 12x10 Xoar prop on 12s5000 zippy packs
when I first set the planes up I was going nuts to get the readings I use a E-Flite meter it works good. I use Dean plugs No problem. I have a lot of flights on the planes they are very reliable.
good luck
Tipover
Jun 23, 2009, 07:09 PM
I use 12x10 Xoar prop on 12s5000 zippy packs
Hi bsipro, I assume you meant a 24x10 prop?
How many cycles on your 5000ma Zippy packs?
I’ve been following all of your giant electric builds, very inspiring. Think I may have stole a couple ideas even.
I’ve been considering a Xoar 26x10. The 26x12 is plenty fast on this plane. Good for IMAC, but just a bit fast for my 3D skills. Waterfalls quickly turn into wicked tumbles unless I really get off the throttle as the nose points down.
Kevin
Tipover
Aug 11, 2009, 12:37 AM
I have about 160 flights on this plane as of 8/10, 80 flights per set of 12s1p 5000 30C Zippy Flightmax packs.
I'm afraid the Zippy packs are slowly petering out. They are coming down a little puffier each flight. After they cool down they firm back up, but they're slowly loosing their shape. I'm using (2) 106 I-Chargers and balance charging at 2C in about 35 minutes. The packs are staying very well balanced and seem to be maintaining capacity. I Sense they are slowly loosing their punch, either that or I'm getting more power hungry :D .
Anyhow, I'm guessing the end is near for the Zippies. Not sure what to try next. I've been very spoiled by 100's of flights on my A123 packs. I wish Hacker made a 250kv version of the A80, then I could run 3p of the 10s A123 packs that I have many of. Sure has been fun while it lasted :)
Kevin
iflytailies
Aug 11, 2009, 06:13 AM
I do like the Xcite (http://www.xcitebattery.com/index.htm) lipos. They offer good performance at reasonable cost. I use them on my Sr. Telemaster for aerotowing, and I have noticed that I am able to perform much more powerful tows over previous brands
http://iflytailies.jimdo.com/
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