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-   -   System Troubleshooting (http://www.Wattflyer.com/forums/showthread.php?t=73549)

rwhitlow 04-12-2014 01:25 PM

System Troubleshooting
 
I have a Hacker A60-20M and a Castle HV-85 ESC on 12S. I have put on 20-10, 20-12, 22-10 & 22-12 and I max out on 30 amps (about 1350 Watts). The KV for the motor is 170 r/v, which should put me in the 7000 rpm range. Im getting about 4000 rpm.

I am using GForce 6S 5000 30C in series. Could this be limiting my current somehow? All my wiring is 10G and I'm using Anderson Power Poles 45 Amp Connectors. I am hoping to pull 1750-2000 Watts out of this setup.

Did not notice a voltage drop on Amp meter while testing.

Any ideas?

Thanks for any input.

Rich
Krzy4RC

kyleservicetech 04-12-2014 07:28 PM

Quote:

Originally Posted by rwhitlow (Post 945252)
I have a Hacker A60-20M and a Castle HV-85 ESC on 12S. I have put on 20-10, 20-12, 22-10 & 22-12 and I max out on 30 amps (about 1350 Watts). The KV for the motor is 170 r/v, which should put me in the 7000 rpm range. Im getting about 4000 rpm.

I am using GForce 6S 5000 30C in series. Could this be limiting my current somehow? All my wiring is 10G and I'm using Anderson Power Poles 45 Amp Connectors. I am hoping to pull 1750-2000 Watts out of this setup.

Did not notice a voltage drop on Amp meter while testing.

Any ideas?

Thanks for any input.

Rich
Krzy4RC

Something is definitely wrong here. What voltage is your pack putting out under load? It should be around 44 Volts DC. If your batteries are over the hill, it doesn't take much voltage drop to really affect your power output. Dropping down to 35 Volts DC under load would put your power input to around 1300 Watts.

I've got the Hacker A50-16M motor, running a 19X12 APC-E prop, with a 12S2P A123 battery pack. This setup is pulling about 75 Amps, and is running about 2700 Watts.

I also have the Hacker A60-5S motor running on a 10S2P A123 pack with a 19X12 prop. That combo is pulling about 75 Amps, and around 2000 watts. These Hacker motors only get slightly warm while running 75 Amps full throttle. (Of course I don't fly the model at full throttle all the time. Doing full throttle on an 18 pound airplane in a dive could lead to problems!)

For your A60-20M motor, www.motocalc.com, a 21X10 prop looks to be a good match. Motocalc indicates this combo with your 12S LiPo battery pack should be pulling about 3100 Watts, 74 Amps, and 6600 RPM. Predicted motor efficiency is 87%.

I doubt if you have a loose connection anywhere. If you did, that connection would get hot, real fast.

I'm guessing your problem is with the transmitter's signal input not applying full throttle. I think there is an LED on the Castle Creations ESC that lights up with it gets full power output. At least there is an LED on my ESC's.

If you've programmed your ESC with the CC USB Dongle, check to see if you've programmed in "Fixed End Points" into the throttle setting. I've left all of my CC ESC's at automatic end point commands. With that, the CC ESC is watching for full throttle, and when it gets it, uses that for the power off and full throttle settings.

fhhuber 04-12-2014 08:17 PM

A few things will make a motor perform below expectations.

1) Excess load. You can draw a huge amount of watts and just make the motor hot.
Probably not your issue this time

2) Magnets damaged from overheating. Again you'll draw high amps and get the motor hot. (making things even worse)
Probably not the issue this time

3) a bad cell in the battery acting more as a resistor than a power source.

4) a bad solder joint or bad crimp at one of your connections, on the ESC or at the motor.

5) Wire having a break in it allowing only partial connection.

6) really bad ESC timing.

7) Connecting packs in parallel but expecting it to act like its in series...
What voltage are you reading?
If 20 to 25... Here's the issue.
It should read in the high 40's (50.4 no load full charge for 12S if the pack is full)

I wouldn't count on a bad connection getting hot with Power Poles and 10 gauge wire at just 30 amps...

kyleservicetech 04-13-2014 01:35 AM

Quote:

Originally Posted by rwhitlow (Post 945252)
I have a Hacker A60-20M and a Castle HV-85 ESC on 12S. I have put on 20-10, 20-12, 22-10 & 22-12 and I max out on 30 amps (about 1350 Watts). The KV for the motor is 170 r/v, which should put me in the 7000 rpm range. Im getting about 4000 rpm.

I am using GForce 6S 5000 30C in series. Could this be limiting my current somehow? All my wiring is 10G and I'm using Anderson Power Poles 45 Amp Connectors. I am hoping to pull 1750-2000 Watts out of this setup.

Did not notice a voltage drop on Amp meter while testing.

Any ideas?

Thanks for any input.

Rich
Krzy4RC


Just thought, if this is your first high powered motor with over 2000 watts, be a little careful with that prop up front. Make danged certain your motor is properly mounted, and that the prop winding up doesn't damage anything, like you :eek:, or anything behind your model. And, keep everything clear of the front of that prop by three or four feet, or more.

Near four horsepower to that prop will blow a LOT of air.

CHELLIE 04-13-2014 02:30 AM

Quote:

Originally Posted by rwhitlow (Post 945252)
I have a Hacker A60-20M and a Castle HV-85 ESC on 12S. I have put on 20-10, 20-12, 22-10 & 22-12 and I max out on 30 amps (about 1350 Watts). The KV for the motor is 170 r/v, which should put me in the 7000 rpm range. Im getting about 4000 rpm.

I am using GForce 6S 5000 30C in series. Could this be limiting my current somehow? All my wiring is 10G and I'm using Anderson Power Poles 45 Amp Connectors. I am hoping to pull 1750-2000 Watts out of this setup.

Did not notice a voltage drop on Amp meter while testing.

Any ideas?

Thanks for any input.

Rich
Krzy4RC

Sounds like your lipos are weak, how old are they, It could be the motor, but the batteries would be the fist thing i would check, also you may want to use 45 to 60C lipos, check your connectors and solder joints too, they may be loose.

http://www.hobbyking.com/hobbyking/s...Lipo_Pack.html

kyleservicetech 04-13-2014 03:16 AM

Quote:

Originally Posted by fhhuber (Post 945289)

I wouldn't count on a bad connection getting hot with Power Poles and 10 gauge wire at just 30 amps...

H'mmm
A contact pulling 30 Amps, and (44 Volts DC on the battery, minus 30 Volts DC at the ESC input) for a 15 Volt loss over that contact will be heating up at 450 watts. Methinks it would get HOT :D :D

kyleservicetech 04-13-2014 03:25 AM

Quote:

Originally Posted by rwhitlow (Post 945252)
I have a Hacker A60-20M and a Castle HV-85 ESC on 12S. I have put on 20-10, 20-12, 22-10 & 22-12 and I max out on 30 amps (about 1350 Watts). The KV for the motor is 170 r/v, which should put me in the 7000 rpm range. Im getting about 4000 rpm.

I am using GForce 6S 5000 30C in series. Could this be limiting my current somehow? All my wiring is 10G and I'm using Anderson Power Poles 45 Amp Connectors. I am hoping to pull 1750-2000 Watts out of this setup.

Did not notice a voltage drop on Amp meter while testing.

Any ideas?

Thanks for any input.

Rich
Krzy4RC

I just checked the CC Website on the CC 85 Amp HV ESC. That ESC does have an led that lights up only when the ESC is getting a full power command from the receiver and your transmitter. With the prop off, check to see if that LED lights up at full throttle.
http://www.castlecreations.com/suppo...User_Guide.pdf (Bottom left corner of page two)

Also, IMHO, it's a good idea to program your ESC with a "Soft Power Down" on LVC (Low Voltage Cutoff) on your battery. A soft power down simply reduces maximum power automatically when your battery pack is nearly discharged. In the process your battery is never discharged below safe limits. Compare this to the LVC simply shutting off your motor on low battery, leaving the pilot to wonder "what the heck happened".

As for me, I'd sooner have a battery get damaged than have my $$$$ model land in the plowed field surrounding our flying field. Yeah, it happened to me several years ago. I spent two weeks rebuilding the model airplane.

fhhuber 04-13-2014 04:04 AM

I usually notice the aircraft performance decline well before LVC, especially with the higher cell count models.

Large difference between output at 50.4v and 44.4v

rwhitlow 04-14-2014 02:35 PM

Thanks for the replies! Here is where I stand.

I have gone through the connections and disassembled and inspected the connectors. They appear to be fine. I also tested for heat during further testing, I noticed no warmth.

The voltage holds at 44 volts till pack gets below 45% or so, then slowly decreases. Seems normal, no big voltage drops.

I checked the throttle on the ESC. It is set on auto cal. I have read some posts stating that with this ESC this sometimes causes the top 25% or so to be lost. i.e. full throttle at 75%.

Batteries are brand new and I need to do an resistance check.

The motor is no getting hot.

Getting 7500 rpm on 20-10, 30 amp. Getting 4500 rpm on 20-12, 30 amp.

No response from CC, yet. But, I sent message over the weekend.

Also, to ease some minds. This is my first large electrics, but not first large plane. Engineering background and plenty of prop scar "experience". I try to be very careful during testing (especially getting up in front enough to see LED's on speed controller!

Here's my plan.

1. Ordered Edge HV 80 to try (I want the data logging anyway). Will send back old one to get tested, inspected, neglected and all sorts of other mean and nasty things (sorry, channeling Arlo Guthrie!)

2. Ordered better Watt meter to make sure we are getting good results. I need a backup anyway. Plus the data log should confirm readings.

3. Ordered some good flex 10G aff Amazon and will re-do the wiring harness and compare the results.

4. Will do a resistance check on batteries. But, I really don't think there is an issue but I will leave no stone un-turned.

In the end that leaves the motor. I will not replace that till all else is tested and proven ok.

As an aside, I purchased a couple of nice switches that I will use with the new ESC as arming switches.

Any comments? Am I heading in the right direction? This has been an interesting troubleshoot as the ESC is a bit of a "black box". I can't wait to see what the issue is! I may need to set us a test stand, like we use to do with the gassers back in the day. That way I can change things a little easier to pin point issues.

I have other planes to fly, so I will find out whats going on before I put it up in the air. I could probably get a flight at this power to see how it flies, but not knowing why keeps me grounded. I don't want to risk something going out in flight.

rwhitlow 04-14-2014 02:35 PM

ps. I have a soft cut-off at 36 volts.

fhhuber 04-14-2014 03:17 PM

12S and its only holding 44 volts? You have a bad cell. 11S can hold above 44 volts.

rwhitlow 04-14-2014 03:43 PM

Maybe my math is wrong...shouldn't it be:

3.7V x 12 = 44.4 volts. Holding 44 at about 60% of battery left seem ok...

Am I missing something? I can order another set of batteries, but I was waiting to see if I should get 5000 mA cells.

fhhuber 04-14-2014 04:12 PM

LiPo full charge is 4.2 v/cell 12 X 4.2 = 50.4 You should be ABOVE 45 volts under load at 30 amps with 5000 mah 20C rated packs... for more than half the useful charge.

I have my telemetry low voltage warning set for 45 volts for my big EDF... saying its time to land. 12S, 5000 mah Sky LiPos, 20 C rated pulling 105 amps peak.

rwhitlow 04-14-2014 04:20 PM

Thanks. I will put on a full charge and track the voltage.

I'll get a couple more packs on order and ramp up on the rating. 40 - 60C, depending on what I find.

fhhuber 04-14-2014 04:40 PM

20C is enough for 99% of what we do. Theoretically you can discharge the packs in 3 minutes if they are rated 20C. Not many people are happy with just a 3 minute flight.

I can remember when 20C were the extreme high discharge rated packs.

Higher rating might gain me a few more amps on the 12S 5000 mah power system driving my big EDF... not enough to get more than 1 or 2 mph more out of it.

The C rating is not the issue causing you to get appx 50% of the power you should be getting from your system.
A bad cell could easily be robbing you of significant power by reduced voltage and high internal resistance.

rwhitlow 04-18-2014 10:28 PM

OK. Here's an update...

I got an e-mail from Castle Support. They suggested I kick back the firmware to 3.2, because this is an older controller and ditch the auto cal on the throttle and do an end-point cal.

Done and now I'm getting 49A with 20x8E prop. Wow! It was that easy. Not sure which did the trick, but I'm glad it worked. Thanks for all the suggestions and help.

The biggest delay, was that my day job kept getting in the way!

We maiden in the morning!

https://www.flickr.com/photos/whitlow/13904808751/

Krzy4RC

kyleservicetech 04-18-2014 10:36 PM

Quote:

Originally Posted by rwhitlow (Post 945800)
OK. Here's an update...

I got an e-mail from Castle Support. They suggested I kick back the firmware to 3.2, because this is an older controller and ditch the auto cal on the throttle and do an end-point cal.

Done and now I'm getting 49A with 20x8E prop. Wow! It was that easy. Not sure which did the trick, but I'm glad it worked. Thanks for all the suggestions and help.

The biggest delay, was that my day job kept getting in the way!

We maiden in the morning!

https://www.flickr.com/photos/whitlow/13904808751/

Krzy4RC

FYI
I've got two Hacker A60's. One is the A60-16M, the other is the A60-5S. Both are running at 60-65 Amps at full power on the ground, and both are running perhaps 10 degrees F above ambient after a flight.

Larry3215 04-19-2014 04:51 PM

Quote:

Originally Posted by rwhitlow (Post 945800)
OK. Here's an update...

I got an e-mail from Castle Support. They suggested I kick back the firmware to 3.2, because this is an older controller and ditch the auto cal on the throttle and do an end-point cal.

Done and now I'm getting 49A with 20x8E prop. Wow! It was that easy. Not sure which did the trick, but I'm glad it worked. Thanks for all the suggestions and help.

The biggest delay, was that my day job kept getting in the way!

We maiden in the morning!

https://www.flickr.com/photos/whitlow/13904808751/

Krzy4RC

So it was mainly an end point problem then. Is the LED on the controller lighting up at full throttle? Thats the final test.

Also, whats your voltage under load at that power level? That will tell you how the packs are doing.

rwhitlow 04-20-2014 01:48 AM

The LED was lighting up full throttle before. I'm not sure if the end points was the only issue. For now, I'm not gonna flash back and see for sure.

My voltage seems normal. Follows the curves for Lipos that I have found posted other places. Pulled about 30 amps and it dropped to about 48 volts and slowly dropped from there.

I also changed my soft cut-off to 38 Volts, just to be safe.

Maidened today and the plane flew great. Plenty of extra power. The 5000 mA batteries are too big. Will probably drop to 3000 mA. Save on weight.

Thanks again for all the help.

kyleservicetech 04-20-2014 01:53 AM

Quote:

Originally Posted by rwhitlow (Post 945965)
The LED was lighting up full throttle before. I'm not sure if the end points was the only issue. For now, I'm not gonna flash back and see for sure.

My voltage seems normal. Follows the curves for Lipos that I have found posted other places. Pulled about 30 amps and it dropped to about 48 volts and slowly dropped from there.

I also changed my soft cut-off to 38 Volts, just to be safe.

Maidened today and the plane flew great. Plenty of extra power. The 5000 mA batteries are too big. Will probably drop to 3000 mA. Save on weight.

Thanks again for all the help.

IMHO, if your model flies OK with the 5000 Mah batteries, I'd just keep on using them. Unless you're flying 3D or something. When flying giant scale models, an extra half pound or so is pretty hard to notice.

Also, just to clarify for folks reading this thread, it's never a good idea to fly to LVC on any battery. To much risk of battery damage. I just fly about 60% of the battery, then land. Your batteries will last longer, and you'll have plenty of juice left to do a go-around on landing, or fly a bit longer because someone is on the field.

Didn't notice, which model airplane do you have for this power system? And, how much does it weigh? If you've got 150 Watts per pound of airplane, that is very good on giant scale models. Your motor can easily handle double that 30 Amps at full power, assuming your ESC can handle it, and the torque from that Hacker motor doesn't twist off the front of your model airplane!

fhhuber 04-20-2014 02:01 AM

Performance is also affected by oz/sq in wing loading and even though 150 watt/lb can let you hover you may not be able to glide better than a rock...

rwhitlow 04-20-2014 02:02 AM

3DHS 74" Edge 540. Getting well over 200 Watt/#.

I don't fly to cutoff, I fly by time. Right now I could get 12 or so minutes of time. I am looking for 3D, so I'll cut the weight. Though I still have the 4000 and 5000 batteries.

kyleservicetech 04-20-2014 02:10 AM

Quote:

Originally Posted by rwhitlow (Post 945971)
3DHS 74" Edge 540. Getting well over 200 Watt/#.

I don't fly to cutoff, I fly by time. Right now I could get 12 or so minutes of time. I am looking for 3D, so I'll cut the weight. Though I still have the 4000 and 5000 batteries.

???
200 watts per pound, with 30 Amps and 48 volts? That's 1440 watts, so at 200 watts per pound, your model would have to weigh around 7 pounds, ready to fly.

A couple of my club members have that model. It is very similar to my Redwing Models MXS-R airplane, running a Hacker A60-5S motor and a 10S2P A123 pack. That A6-5S motor has as much power as a DLE 30 gasoline engine.

Larry3215 04-20-2014 02:28 AM

Quote:

Originally Posted by rwhitlow (Post 945965)
The LED was lighting up full throttle before. I'm not sure if the end points was the only issue. For now, I'm not gonna flash back and see for sure.

My voltage seems normal. Follows the curves for Lipos that I have found posted other places. Pulled about 30 amps and it dropped to about 48 volts and slowly dropped from there.

I also changed my soft cut-off to 38 Volts, just to be safe.

Maidened today and the plane flew great. Plenty of extra power. The 5000 mA batteries are too big. Will probably drop to 3000 mA. Save on weight.

Thanks again for all the help.

Unless you followed castles recommended start up proceedure every single time you started the motor, the auto-calibrate function on the Castle esc's could end up having the esc "think" it was seeing full throttle when it wasnt.

You could easily end up with the esc thinking it was at full throttle - and turn on the LED - when you were at 1/2 throttle, 1/4 throttle or less.

The auto calibrate function only works properly if you immediately go to full throttle when you start the motor and hold it there for 4 seconds.

If you are like most people and start the motor at part throttle to taxi or to slowly power up on the bench, then the auto calibrate function would or could decide that 1/4 throttle was full throttle and call it quits. After that, you could never get beyond that initial part throttle point.

Thats the main reason Castle quit recommending the auto calibrate setting.

Its a good idea in theory - but almost no one actually reads the directions and follows them :D

rwhitlow 04-20-2014 02:55 AM

That may be so, but directions were followed this time...

It was a systematic troubleshoot.


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